CA2052550A1 - Membrane process for treating a mixture containing dewaxed oil and dewaxing solvent - Google Patents
Membrane process for treating a mixture containing dewaxed oil and dewaxing solventInfo
- Publication number
- CA2052550A1 CA2052550A1 CA002052550A CA2052550A CA2052550A1 CA 2052550 A1 CA2052550 A1 CA 2052550A1 CA 002052550 A CA002052550 A CA 002052550A CA 2052550 A CA2052550 A CA 2052550A CA 2052550 A1 CA2052550 A1 CA 2052550A1
- Authority
- CA
- Canada
- Prior art keywords
- dewaxed oil
- membrane
- dewaxing solvent
- cross
- polysiloxane
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000002904 solvent Substances 0.000 title claims abstract description 61
- 239000012528 membrane Substances 0.000 title claims description 71
- 238000000034 method Methods 0.000 title claims description 32
- 239000000203 mixture Substances 0.000 title description 4
- -1 polysiloxane Polymers 0.000 claims abstract description 66
- 229920001296 polysiloxane Polymers 0.000 claims abstract description 41
- 229920001971 elastomer Polymers 0.000 claims abstract description 19
- 239000000806 elastomer Substances 0.000 claims abstract description 19
- 229910000077 silane Inorganic materials 0.000 claims abstract description 14
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims abstract description 12
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 claims abstract description 7
- PWAXUOGZOSVGBO-UHFFFAOYSA-N adipoyl chloride Chemical compound ClC(=O)CCCCC(Cl)=O PWAXUOGZOSVGBO-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000012466 permeate Substances 0.000 claims description 32
- 239000003431 cross linking reagent Substances 0.000 claims description 25
- 239000012465 retentate Substances 0.000 claims description 16
- 230000003247 decreasing effect Effects 0.000 claims description 14
- 125000000217 alkyl group Chemical group 0.000 claims description 11
- 125000003118 aryl group Chemical group 0.000 claims description 10
- 125000000753 cycloalkyl group Chemical group 0.000 claims description 10
- 125000002877 alkyl aryl group Chemical group 0.000 claims description 9
- 125000003710 aryl alkyl group Chemical group 0.000 claims description 9
- 239000001257 hydrogen Substances 0.000 claims description 9
- 229910052739 hydrogen Inorganic materials 0.000 claims description 9
- 239000007791 liquid phase Substances 0.000 claims description 8
- 229920001228 polyisocyanate Polymers 0.000 claims description 8
- 239000005056 polyisocyanate Substances 0.000 claims description 8
- 238000000926 separation method Methods 0.000 claims description 7
- 238000004132 cross linking Methods 0.000 claims description 5
- 125000004122 cyclic group Chemical group 0.000 claims description 5
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 5
- RQVFGTYFBUVGOP-UHFFFAOYSA-N [acetyloxy(dimethyl)silyl] acetate Chemical group CC(=O)O[Si](C)(C)OC(C)=O RQVFGTYFBUVGOP-UHFFFAOYSA-N 0.000 claims description 3
- CPUDPFPXCZDNGI-UHFFFAOYSA-N triethoxy(methyl)silane Chemical group CCO[Si](C)(OCC)OCC CPUDPFPXCZDNGI-UHFFFAOYSA-N 0.000 claims description 2
- 230000000694 effects Effects 0.000 claims 1
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 abstract description 15
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 abstract description 12
- 230000008384 membrane barrier Effects 0.000 abstract 1
- 210000004379 membrane Anatomy 0.000 description 46
- 239000003921 oil Substances 0.000 description 30
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 12
- 230000004907 flux Effects 0.000 description 8
- 150000002430 hydrocarbons Chemical class 0.000 description 7
- 239000007788 liquid Substances 0.000 description 7
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 6
- 229920002239 polyacrylonitrile Polymers 0.000 description 6
- 239000004215 Carbon black (E152) Substances 0.000 description 5
- 229930195733 hydrocarbon Natural products 0.000 description 5
- 239000010687 lubricating oil Substances 0.000 description 5
- 239000002131 composite material Substances 0.000 description 4
- 235000013870 dimethyl polysiloxane Nutrition 0.000 description 4
- SCPYDCQAZCOKTP-UHFFFAOYSA-N silanol Chemical compound [SiH3]O SCPYDCQAZCOKTP-UHFFFAOYSA-N 0.000 description 4
- 102100038916 Caspase-5 Human genes 0.000 description 3
- 101100112336 Homo sapiens CASP5 gene Proteins 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 101100273286 Mus musculus Casp4 gene Proteins 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- INQOMBQAUSQDDS-UHFFFAOYSA-N iodomethane Chemical compound IC INQOMBQAUSQDDS-UHFFFAOYSA-N 0.000 description 3
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 3
- 229920000728 polyester Polymers 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- XMSXQFUHVRWGNA-UHFFFAOYSA-N Decamethylcyclopentasiloxane Chemical compound C[Si]1(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O1 XMSXQFUHVRWGNA-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical group CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 2
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 2
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 2
- 239000008186 active pharmaceutical agent Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 125000002704 decyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 2
- 239000004205 dimethyl polysiloxane Substances 0.000 description 2
- PZPGRFITIJYNEJ-UHFFFAOYSA-N disilane Chemical compound [SiH3][SiH3] PZPGRFITIJYNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 2
- 239000000706 filtrate Substances 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 2
- 150000002576 ketones Chemical class 0.000 description 2
- 125000000740 n-pentyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 2
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- FZHAPNGMFPVSLP-UHFFFAOYSA-N silanamine Chemical compound [SiH3]N FZHAPNGMFPVSLP-UHFFFAOYSA-N 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- QCMKERDUVZTUHU-UHFFFAOYSA-N 1-[diamino(butyl)silyl]butane Chemical compound CCCC[Si](N)(N)CCCC QCMKERDUVZTUHU-UHFFFAOYSA-N 0.000 description 1
- 125000000590 4-methylphenyl group Chemical group [H]C1=C([H])C(=C([H])C([H])=C1*)C([H])([H])[H] 0.000 description 1
- ZOQBUHIQUHKBFX-UHFFFAOYSA-N C(C)(=O)O[Si](OC(C)=O)(OC(C)=O)OC(C)=O.C1(=CC=C(C=C1)[Si](OC(C)=O)(OC(C)=O)OC(C)=O)C.C(C1=CC=CC=C1)[Si](OC(C)=O)(OC(C)=O)OC(C)=O Chemical compound C(C)(=O)O[Si](OC(C)=O)(OC(C)=O)OC(C)=O.C1(=CC=C(C=C1)[Si](OC(C)=O)(OC(C)=O)OC(C)=O)C.C(C1=CC=CC=C1)[Si](OC(C)=O)(OC(C)=O)OC(C)=O ZOQBUHIQUHKBFX-UHFFFAOYSA-N 0.000 description 1
- ODRMHELHYNQDFY-UHFFFAOYSA-N CO[Si](OC(C)=O)(OC(C)=O)OC(C)=O.CO[Si](OC(C)=O)(OC(C)=O)OC Chemical compound CO[Si](OC(C)=O)(OC(C)=O)OC(C)=O.CO[Si](OC(C)=O)(OC(C)=O)OC ODRMHELHYNQDFY-UHFFFAOYSA-N 0.000 description 1
- 241000518994 Conta Species 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- YHYITPYNGUZSNF-UHFFFAOYSA-N O=C(C1=CC(C(Cl)=O)=CC=C1)Cl.Cl.Cl Chemical compound O=C(C1=CC(C(Cl)=O)=CC=C1)Cl.Cl.Cl YHYITPYNGUZSNF-UHFFFAOYSA-N 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- QZKNEHDHUFHVQD-UHFFFAOYSA-N [acetyloxy(dimethyl)silyl] acetate;[diacetyloxy(methyl)silyl] acetate Chemical compound CC(=O)O[Si](C)(C)OC(C)=O.CC(=O)O[Si](C)(OC(C)=O)OC(C)=O QZKNEHDHUFHVQD-UHFFFAOYSA-N 0.000 description 1
- YXJHOYOBVZPTJD-UHFFFAOYSA-N [acetyloxy-[diacetyloxy(methyl)silyl]-methylsilyl] acetate Chemical compound CC(=O)O[Si](C)(OC(C)=O)[Si](C)(OC(C)=O)OC(C)=O YXJHOYOBVZPTJD-UHFFFAOYSA-N 0.000 description 1
- MRHIKEHTLHXDRQ-UHFFFAOYSA-N [diamino(methyl)silyl]methane Chemical compound C[Si](C)(N)N MRHIKEHTLHXDRQ-UHFFFAOYSA-N 0.000 description 1
- 125000003668 acetyloxy group Chemical group [H]C([H])([H])C(=O)O[*] 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229920006037 cross link polymer Polymers 0.000 description 1
- 125000000582 cycloheptyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 1
- 125000000113 cyclohexyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 1
- 125000000640 cyclooctyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C([H])([H])C1([H])[H] 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000037213 diet Effects 0.000 description 1
- 235000005911 diet Nutrition 0.000 description 1
- SIWNOIGHWNVCHR-UHFFFAOYSA-N diethoxy(dimethyl)silane;triethoxy(methyl)silane Chemical compound CCO[Si](C)(C)OCC.CCO[Si](C)(OCC)OCC SIWNOIGHWNVCHR-UHFFFAOYSA-N 0.000 description 1
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 1
- YYLGKUPAFFKGRQ-UHFFFAOYSA-N dimethyldiethoxysilane Chemical compound CCO[Si](C)(C)OCC YYLGKUPAFFKGRQ-UHFFFAOYSA-N 0.000 description 1
- GKOZKEKDBJADSV-UHFFFAOYSA-N disilanol Chemical compound O[SiH2][SiH3] GKOZKEKDBJADSV-UHFFFAOYSA-N 0.000 description 1
- 229920006332 epoxy adhesive Polymers 0.000 description 1
- 125000001301 ethoxy group Chemical group [H]C([H])([H])C([H])([H])O* 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000013007 heat curing Methods 0.000 description 1
- 125000004051 hexyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 125000000959 isobutyl group Chemical group [H]C([H])([H])C([H])(C([H])([H])[H])C([H])([H])* 0.000 description 1
- 125000000956 methoxy group Chemical group [H]C([H])([H])O* 0.000 description 1
- ZJBHFQKJEBGFNL-UHFFFAOYSA-N methylsilanetriol Chemical compound C[Si](O)(O)O ZJBHFQKJEBGFNL-UHFFFAOYSA-N 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000004123 n-propyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000001624 naphthyl group Chemical group 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- PUIBKAHUQOOLSW-UHFFFAOYSA-N octanedioyl dichloride Chemical compound ClC(=O)CCCCCCC(Cl)=O PUIBKAHUQOOLSW-UHFFFAOYSA-N 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000002914 sec-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 1
- 125000005372 silanol group Chemical class 0.000 description 1
- 229920005573 silicon-containing polymer Polymers 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000000638 solvent extraction Methods 0.000 description 1
- 239000011877 solvent mixture Substances 0.000 description 1
- 125000004079 stearyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- LFQCEHFDDXELDD-UHFFFAOYSA-N tetramethyl orthosilicate Chemical compound CO[Si](OC)(OC)OC LFQCEHFDDXELDD-UHFFFAOYSA-N 0.000 description 1
- 125000003944 tolyl group Chemical group 0.000 description 1
- 238000000108 ultra-filtration Methods 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
- 125000005023 xylyl group Chemical group 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/70—Polymers having silicon in the main chain, with or without sulfur, nitrogen, oxygen or carbon only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
- C08G77/48—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G31/00—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for
- C10G31/11—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for by dialysis
Abstract
ABSTRACT OF THE INVENTION
D#79,546 Charge containing dewaxed oil and dewaxing solvent (typically methyl ethyl ketone and toluene) is treated to separate dewaxing solvent by use of a separating elastomer membrane barrier of a polysiloxane which has been cross-linked as with toluene diisocyanate, adipoyl dichloride, a dialkoxy silane, or a diacetoxy silane.
D#79,546 Charge containing dewaxed oil and dewaxing solvent (typically methyl ethyl ketone and toluene) is treated to separate dewaxing solvent by use of a separating elastomer membrane barrier of a polysiloxane which has been cross-linked as with toluene diisocyanate, adipoyl dichloride, a dialkoxy silane, or a diacetoxy silane.
Description
, ~ ' ; 2 1 ~
5MEMBRANE PROCESS F`OR TP~EATING A
M XTURE CQNTAININIJ DEWAXED OIL
AND DEWAXING SOLVENT
D#79,546 10FIELD OF THE INVENTIO~
This invention relat~s to a procPss for tr~ating a charge containing dewaxing solvent and dewaxed oil. More particularly it relates to use of membrane technology to separate dewaxing solvent from dewaxed oil.
BACKGROUND OF THE INVENTION
As is well known to those skilled in the art, hydrocarbon stocks used for the preparation of lubricating oil contain undesirable components which are removed during processing to permit attainment of a product which is characterized by desired properties. Typically a charge stock is subjected inter alia to a dewaxing operation which decreases the wax content and desirably lowers the pour point and the cloud point of the lubricating oil stock.
Dewaxing may be effected by mixing a dewaxing solvent, such as methyl ethyl ketone or methyl isobutyl ketone, optionally in the presence of a hydrocarbon such as toluene or ~ylene, with the charge oil and cooling the mixture below the desired pour point, typically to minus 5F~minus 20F, say minus 10F, at which point wax precipitates. The wax is filtered; and the dewaxed oil - dewaxing solvent mixture is recovered.
CG579546 . PIN
03/06~91 This rPcovered mix~ure has classically been flashed to recover solvent-free lubricating oil stock and solvent which is free of lubricating oil.
Those sXilled in the art have attempted to improve the economics of this process by utilizing membrane technology to separate dewaxing solvent from dewaxed oil.
Illustrative of such prior art attempts may be the following:
USP 4,985,138 to Pasternak discloses a cross-linked polyimine membrane.
European Patent Specification 0 220 753 Al to Bitter et al discloses use of a halogen-substituted silicone membrane.
USP 4,678,555 to Wernick discloses use of cellulose acetate membranes.
European Patent Specification 0 125 907 A1 to Wight discloses use of a polyimide membrane containing -CO-N0-linkages.
USP 4,617,126 to Funk et al discloses use of a polysulfone membrane.
Additional background may be obtained from the references set forth in these patents.
It is an object of this invention to provide a process for treating a charge containing dewaxing solvent and dewaxed oil. Other objects~ will be apparent to those skilled in the art.
CGS79546 . P~N
STATEMENT O _THE INV~TION
In accordance with certain of the aspects, this lnvention is directed to a process for treating a charge containing dewaxing solvent and dewaxed oil which comprises passing said charge containing dewaxing solvent and dewaxed oil into con~act wit~l, as separating membrane, a non-porous elastomer separating polysiloxane membrane layer 10 which has been cross-linked with, as ~ cross-linXing agent, (i) a polyisocyanate or (ii) a poly(carbonyl chloride) or (iii) a silane R4_a Si (A~ a wherein A is -OH, -NH2 -OR, or -OOCR, a is 2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group; 5 maintaining a pressure drop across said membrane ther~by forming a high pressure retentate containing increased oontent of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of 2S said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of ~0 said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane thereby maintaining said charge de~axing solvent and dewaxed oil and said retentate in liquid phase;
CGS~DS~6 . P~N
03/06/f~l _ 3 _ recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and recovering said rletentate containing increased content of dewaxed oi.l and decreased content of dewaxing solvent.
DESCRIPTION OF THF INVENTION
The lube oil stocks which may be treated by dewaxing may include distillate stocks, de~sphalted oils, raffinates from solvent extraction of distillate, hydrotreated oils, hydrocracked distillates, etc. typically ranging in viscosity at 100F from about 30 SUS to 4000 SUS. Typically such a charge may be characterized by the following:
TABLE
ProPertv Ranqe Preferred Typical ibp F 590-goo 600-800 675 50% bp F 725-1100 800-900 850 90% bp F 800-1350 850-950 920 Viscosity SUS/100 F35-3500 40-100 54.63 60 F50-10,000 100-400 348.7 API Gravity20-30 22-29 25.8 Sp. Gr 15C/15C 0.870-0.895 0.880-0.890 0.890 Pour Poi~t F90-125 95-110 95+
Flash Point F 360-600 385-560 460 Refractive Index @ 70C1.4720-1.49401.4755-1.4920 1.4840 CGS7a5~6 . PTN
03/06/9~ _ 4 --This waxy oil charge ~100 volumes) is mixed with 100-1000 volumes, preferably 200-~,00 volumes, say 200 volumes (depending on the viscosity gracle and wax content of the feedstock) of ketone dewaxing solvent - such as acetone or preferably methyl ethyl ketone or methyl isobutyl ketone preferably diluted with a hydrocarbon solvent to produce dewaxing s~lvent. In a preferred embodiment, there may be added to 100 volumes of waxy oil charge, dewa~ing solvent 100 -- IS'D
~ 3~) containin~_56-~ volumes of ketone such as methyl ethyl ketone lc~o-- ~ o P 1O~1L~I plus bO-~5 volumes of a hydrocarbon solvent such as toluene or xylene. The mixture is cooled to minus 5F-minus 20F, say minus 10F, during which cooling, solid wax precipitates from the waxy oil charge. Typically a mid~continent distillate may be cooled to minus lO~F to obtain a 0F pour point 100 neutral oil. Wax is filtered in a rotary vacuum filter to yield a dewaxed oil filtrate.
In accordance with practice of the process of this invention, this filtrate, containing dewaxing solvent and dewaxed oil, is passed into contact with, as a separation membrane, a non-porous separating elastomer membrane layer.
THE MEMBRANE ASSEMBLY
Practice of the process of this invention may be carried out by use of a composite structure which in one preferred embodiment may include (i) a carrier layer which provides mechanical strength, (ii) a porous support layer, and (iii) a separating elastomer membrane layer across which separation occurs.
The composlte structure of this invention includes a multi-layer assembly which in the preferred CGS79546 . PTN
embodiment preferably includes a porous carrier layer which provides mechanical strength and support to the assemblyn THE CARRIER I~YER
This carrier layer, when used, is characterized by its high degree of porosity and mechanical strength. It may be fibrous or non-fibrous, woven or non-wovenO In the preferred embodiment, the carrier layer may be a porous, flexible, woven fibrous polyester. A typical polyester carrier layer may be formulated of non-woven, thermally-bonded strands.
THE POROUS SUPPORT LAYER
The porous support layer (typically an ultrafiltration membrane) which may be used in practice of this invention is preferably formed of polyacrylonitrile polymer.
Typically the polyacrylonitrile may be of thickness of 40-80 microns, say 50 microns and is preferably characterized by a pore size of less than about 500A and typically about 200A.
This corresponds to a molecular weight cut off of less than about 50,000, typically about 40,000.
THE SEPARATING LAYER
The separating layer which permits attainment of separation in accordance with the process of this invention includes a non-porous elastomer film or membrane of thickness 1-5 microns, say about 1.5 microns of a polysiloxane polymer of molecular weight Mn of about 550-150,000, preferably 550-4200, more preferably say about 1,750 (prior to cross-linking), which is cross-linked with, as cross-linking agent, (i) a polyiso-cyanate, or (ii~ a poly(carbonyl chloride) or (iii) R4~ Si(A)a CGS79546. PTN
wherein A is -OH, -H~2, OR~ or -OOCR, a is 2, 3, or 4, and R
is hydrogen, alkyl, aryl, cycloalkyl, alkaryl, or aralkyl.
The polysiloxanes which may be employed, as elastomer membranes, in practice of the process of this invention may include membranes of molecular weight Mnf 550-150,000, say 1,750 of halogen-free polysiloxanes which contain the repeating unit -si-o- and wherein the silicon atoms bear hydrogen or a hydrocarbon group. Preferably the repeating units are of the form --L sl o ~ R n In the above formula, R may be hydrogen or a hydrocarbon group selected from the group consisting of alkyl, aralkyl, cycloalkyl, aryl, and alkaryl, including such radicals when inertly substituted. Wh~n R i5 alkyl, it may typically be methyl, ethyl, n-propyl, iso-propyl, n-butyl, i-butyl, sec-butyl, amyl, octyl, decyl, octadecyl, etc. When R is aralkyl, it may typically be benzyl, beta-phenylethyl, etc. When R is cycloalkyl, it may typically be cyclohexyl, cycloheptyl, cyclooctyl, 2-methylcycloheptyl, 3-butylcyclohexyl, 3-methlcyclohexyl, etc. When R is aryl, it may typically be phenyl, naphthyl, etc. When R is alkaryl, it may typically be tolyl, xylyl, etc. R may be inertly substituted i.e. it may bear a non-reactive substituent such as alkyl, aryl, cycloalkyl, ether, etc. Typically inertly substituted R groups may include 2-ethoxyethyl, carboethoxymethyl, 4-methyl cyclohexyl, p-methylphenyl, p-ethylbenzyl, 3-ethyl-5-methylphenyll etc. The preferred R groups may be lower alkyl, i.e. Cl-C¦loalkyl, groups including e.g. methyl, ethyl, n-CGS79546.PTN
propyl, i-propyl, butyls, amyls, hexyls, octyls, decyls, etc.
R may preferably ba methyl~
The preferred of these halogen- ree poly-siloxanes are the di-silanol-terminated poly(dimethyl siloxanes) of lower molecular weight, typically 550-150,000, preferably 550-4200, more preferably, say 1,750. These polysiloxane elastomer membranes, which yield good Flux and Separation, may be characterized by the formula:
lCH3 r CH3 ~ IH3 HO - Si - O - L- Si - O - I _ Si - OH
CH2 CH3 ~ CH3 2Q wherein n is about 7-2000, say 24.
A preferred group of polysiloxanes may be poly-dimethyl siloxanes which are silanol terminated. Illustration polysiloxanes which may be employed may be those set forth in the Table which follows:
CGS79546~PTN
TABLE
Molecular Weight A Silanol terminated polydimet:hyl siloxane 550 B " ~ 1750 C " ~ 4200 D " ~ 58,000 E " " 110,000 F " ~ 150,000 G Acetoxy " " 3G,000 H Methoxy " " 27,000 I Ethoxy " " 950 J Carbinol " " 1250 K Aminopropyl 2500 dimethyl " "
It is a feature of the process of this invention that the sili~one membranes are cross-linked. In the case of the non-cyclic silicones, which bear reactive terminal groups typified by -OH or -NH2, they may be cross-linked by (i) a polyisocyanate, (ii) a poly(carbonyl chloride) or (iii) a silane R4-a Si (A)a wherein A is -OH, -NH2, -OR, or -OOCR, a is 2, 3, or 4, and R
may be as noted supra. The R groups need not be all the same.
It will be apparent that cross-linking is effected by reaction between the reactive terminal group of the non-cyclic silicone and the A group of the silane; and accordingly these groups whlch are to react should be different from each other. Preferably the silicone may be amino terminated, more preferably hydroxy terminated, and in the CGS79546.PTN
silane, A is preferably -OR or -OOCR. When the silane contains the moiety -OR or -OOCR, and the silicone is -OH terminated for example, the cross-linked polymer includes linkages of the type.
-- si--o--si It will be apparent that the silicone may be -OR
or -OOCR terminated, in which instance the silane may preferably contain an -OH moiety. It appears that no cross-linking may occur when the silicone is terminated by hydrogen.
When the silicone is a cyclic silicone, typified for example by decamethyl cyclopentasiloxane, it will be apparent that the molecule bears no terminal groups. In this instance, cross-linking is effected by breaking an Si O bond in the ring by reaction with the cross-linking agents.
It will be apparent that when A is -OR, the compound is an alkoxy silane; and when A is -OOCR, the compound is an acyloxy silane. When A is -NH2 OR -OH, the compound is an aminosilane qr a hydroxy silane.
Typical alkoxy silanes which may be employed may include:
CG5795~6 . P~N
TABLE
methyl triethoxy silane dimethyl diethoxy silane 5dimethyl dimethoxy silane ethyl trimethoxy silane phenyl triethoxy silane benzyl trimethoxy silane p-tolyl trimethoxy silane 101,2-dimethoxytetramethyl disilane tetramethoxy silane Typical acyloxy silanes ~hich may be employed may include:
TABLE
dimethyl diacetoxy silane methyl triacetoxy silane 20diethyl diacetoxy silane dipheny diacetoxy silane benzyl tri acetoxy silane p-tolyl tri acetoxy silane tetra acetoxy silane 251,2-di-acetoxytetramethyl disilane 1,2-dimethyltetra acetoxy disilane Mixed alkoxy, acyloxy silanes may be employed typified by:
~0 TABLE
dimethoxy diacetoxy silane methoxy triacetoxy silane cGs7as46 . PIN
Illustrative aminosilanes may include dimethyl diamino silane or dibutyl diaminosilane; illustrative hydroxy silanes may include diet}lyl di:hydroxy silane or methyl trihydroxy silane.
Typical polyisocyanat~s may include, the first listed being preferred:
TABI,E
toluene diisocyanate phenylene diisocyanate hexamethylene diisocyanate toluene tri-isocyanate Typical poly(carbonyl chlorides) may include, the first listed being preferred:
TABLE
~dipoyl dichloride isophthaloyl dichloride suberoyl dichloride Formation of the cross-linked elastomer silicone membrane may be carried out in a solution, in inert diluent-solvent (typified by a hydrocarbon such as commercial hexane) of 5-15, say lOw% of the non-halogenated polysiloxane plus 1-lOw%, say 4w% of cross-linking agent.
This solution may be solvent cast as a 0.5-4 mil, say 2 mil film onto a support layer (on a carrier layer) typically at say 25C. Thereafter it is cured at 110C-140C, say 125C for 10-20 minutes, say 15 minutes to form a film 1 5, say 1.5 thick.
CGS79546.PTN
T~IE_COMPOSITE MEMBRANE
It is a f eature oi- this invention that it may utilize a composite membrane wh:ich comprises (i) a carrier layer characterized by mechanica:L strength, for supporting a porous support layer and a separating layer ~ii) a porous support layer sush as a polyacrylonitrile membrane of 10-80 microns, and of molecular weight cut-off of 25,000-100,000, and (iii) as a non-porous separating layer a polysiloxane elastomer membrane which has been cross-linked with, as cross-linking agent, a polyisocyanate, or a poly(carbonyl chloride) or R4~ Si (A), wherein A is -OH, -NH~ -OR, or -OOCR, a is 2, 3, or 4, and R is alkyl, aryl, cycloalkyl, alkaryl, or aralkyl.
It is possible to utilize a spiral wound module which includes a non-porous separating layer membrane mounted on a porous support layer and a carrier layer, the assembly being typically folded and bonded or sealed along all the edges but an open edge - to form a bag-like unit which preferably has the separating layer on the outside. A cloth spacer, serving as the permeate or discharge channel is placed within the bag-like unit. The discharge channel projects from the open end of the unit.
There then placed on one face of the bag-like unit, adjacent to ~he separating layer, and coterminous therewith, a feed channel sheet - typically formed of a plastic net.
The so-formed assembly is wrapped around a preferably cylindrical conduit which bears a plurality of perforations in the wall - preferably in a linear array which is as long as the width of the bag-like unit. The projecting portion of the discharge channel of the bag-like unit is placed GGS79546 . PIN
03/06/9l -- 13 --over the perforations of ~he conduit; and the bag-like unit is wrapped around the conduit to form a spiral wound con-figuration. It will be apparent that, although only one feedchannel is present, the single feed channel in the wound assembly will be adjacent to two faces of ~he membrane layer~
The spiral wound configuratlon may be formed by wrapping the assembly around the conduit a pLurality of times to form a readily handleab]e unit. The unit is fitted within a shell (in manner comparable to a shell-and-t:ube heat exchanger) provided with an inlet at one end and an outlet at the other. A baffle-like seal between the inner surfaoe of the shell and the outer surface of the spiral~wound unit prevents fluid from bypassing the operative membrane system and insures that fluid enters the system principally at one end. The permeate passes from the feed channel, into conta~t with the separating layer and thence therethrough, into the permeate channel and thence therethrough to and through the perforations in the conduit through which it is withdrawn as net permeate.
In use of the spiral wound membrane, charge liquid is permitted to pass through the plastic net which serves as a feed channel and thence into contact with the non-porous separating membranes. The liquid which does not pass through the membranes is withdrawn as retentate. The liquid which permeates the membrane passes into the volume occupied by the permeate spacer and through this permeate channel to the perforations in the cylindrical conduit through which it is withdrawn from the system.
In another embodiment, it is possible to utilize the system of this invention as a tubular or hollow fibre. In this embodiment, the polyacrylonitrile porous support layer may be extruded as a fine tube with a wall thickness of typically 0.001-O.lmm. The extruded tubes are passed through a bath of CG579546 . E'T2i silicone which is cross-linked an~1 cured in situ. A bundle of these tubes is secured (wi~ an epoxy adhesive) at each end in a header; and the fibres are cut so that they are flush with the ends of the header. This tube bundle is mounted within a shell in a typical shell-and-tu~e assembly.
In operation, the charge liquid is admitted to the tube s~de and passes through the inside of the tubes and exits as retentate. During passage through the tubes, per~eate pas~es thrQugh the non~porous separating layer and permeate is collected in the shell side.
PRESSURE DRIVEN PROCESS
It is a feature of the non-porous cross-linked elastomer separating layer that it is found to be particularly effecti~e when used in a pressure driven piocess. In a pressure driven process, a charge liquid containinq a more permeable and a less permeable component is maintained in contact with a non~porous separating layer; and a pressure drop i5 maintained across that layer. A portion of the charge liquid dissolves into the membrane and diffuses therethrough.
The per~eate passes through the membrane and exits as a liquid.
In practice of the process of this invention, the charge containing dewaxing solvent and dewaxed oil in liquid phase typically at 20C-40C, say 25C may be passed into contact with the non-porous elastomer separating layer of the membrane of this învention. A pressure drop of about 500-1000 psi, say 800 psi is commonly maintained across the me~brane. The feed or charge side of the membran~ is at pressure sufficient ot drlve permeate across the membrane and commonly about 800 psig; and the permeate or discharge side of the membrane is at about atmospheric pressure. The feed is CG57~54 6 . P7N
03/06/9l -- 15 --passed over the surface (ca three inches in diameter in one embodiment) of the membrane at a rate (e.g. of about 1200 ml/min) which minimizes ~he possibility of concentration polarization.
The permeate which passes through the membrane includes increased content of dewaxing solvent and decreased content of dewaxed oil; and the retentate includes increased content of dewaxed oil and decreased content of dewaxing solvent.
Typically when the charge to the membrane contains(per 100 parts of oil) 100-1100, preferably 200-600 parts, say 200 parts of dewaxing solvent, the permeate may be found to typically contain about 96w% of dewaxing solvent.
Permeate is recovered in liquid phase.
Separation may typically be carried out at a flux of 20-40, say 37.1 kilograms per square meter per hour (kmh). Typically the membranes may have a rejection of more than 80% and commonly 70%-90%, say 89.7%.
Rejection % =
(Feed Concentration - Permeate Concentration) x 100 Feed Concentration.
Practice of the process of this invention will be apparent to those skilled in the art from the following examples wherein, as elsewhere in this specification, all percentages are percentages by weight unless otherwise stated.
CGS79546 . PIN
03~0b/91 -- 16 --D ~ RIPTI N OF SPEC~FIC EMBODI~ENTS
EXA~PLE I
In this Example, which represents the best mode of carrying out the process of this invention, the elastomer separating membrane is formed on the DUY-L brand (of Daicel Corp.) composite which includes as carrier layer the woven polyester backing described supra. The porous support layer is the commercially available polyacrylonitrile (PAN) having a 40,000 mole~ular weight cut off.
The solution of elastomer in commercial hexane containing ~i) 9w% disilanol-terminated poly dimethyl siloxane (m.w. 1750) and (ii) 4w~ 2,4-toluene diisocyanate is poured ~5 onto the porous support layer at 25C to coat a film of about 2 ~il thickness, followed by heat curing at 125C for 15 minutes.
This membrane (three inch diameter circle) is mounted in a standard cell. There is admitted to the cell and to the non-porous elastomer separating layer a charge con-taining one part by weight of dewaxed SNO-100 oil and 1 part by weight of methyl ethyl ketone and 1 part by weight of toluene.
Separation is carried out at room temperature of 25~C and a charge (and retentate) pressure of about 800 psig.
Feed is at 25C/800 psig at flow rate of 1200 ml/min.
Permeate pressure is atmosphexic. Selectivity is measured and reported as % Rejection which is calculated at 100 x (the quantity of dewaxed oil in the feed minus the quantity of dewaxed oil in the permeate) divided by the quantity of dewaxed oil in the feed. Clearly a higher Selectivity is desired, as this means that the retentate desirably contains less dewaxing CG579546 . P~N
03/06/9l -- 17 --solvent and the permeate desirably contains more solvent. Flux is measured as kilograms per square meter per hour (kmh).
In this ~xample, the Selectivity is 89.7%
rejection and the Flux is 37.1.
_XAMPLES II-V
In this series of Examples, the procedure o~
Example I is followed except that in Example II, the toluene diisocyanate is present in amount of 2%, in Examples III-IV the cross-linking agent is adipoyl dichloride (2w% and 4w%
respectively) and in Example V, no cross-linking agent is employed.
TABLE
Selectivity Flux Example % Re~ection (kmh~
I 89.7 37.1 II 87.4 36.8 III 84.2 39.1 IV 83.5 37.2 V* 68.2 29.6 * Conntrol Example EXAMPLES VI-Ix In this series of Examples, the procedure of Example I is followed except that the polysiloxane is decamethyl cyclopentasiloxane CG579546 . P~N
03/06~9~ -- 18 --(CH3~ Si - - Si ICH3~2 o o si - o -- si - o - si ICH3~2 ~CH3~2 ICH3~2 present as 5w% solution in commercial hexane which also contains 5w% of a multifunctional cross-linking agent as noted in the Table which follows:
TABLE
Example Cross-Linkinq Selectivit~ Flux Aqent (~Reiection) (kmh~
VI dimethyl diethoxy silane 77.4 29.7 VII methyl triethoxy silane 77.4 33.4 VIII dimethyl diacetoxy silane 82.5 34.0 IX* no cross-linking agent 77.4 30.6 From inspection of Examples I-IX*, it will be apparent that the technique of this invention permits attainment of results (in terms of Selectivity and Flux~ which are consistently higher than those attained when no cross-linking agent is employed. Best results appear to be attained in Example I using a linear disilanol terminated poly dimethyl siloxane which has been cross-linked with toluene diisocyanate.
,,, EXAMPLES X*-XV*
CGS795~ 6 . P~N
In this series of Ex,amples, a series of silanol-terminated polydimethyl siloxanes of different molecular weight (in lOw% hexane solution) were formed into similar elastomer membranes which were not chemically cross-linked.
TABLE
ExampleMolecular _lectivity Flux ~ gb~_ Reiection~ (kmh) X* 150,000 47.7 23.3 XI* 110,000 48.5 26.3 XII* 58,000 53.8 24.1 XIII* 4,200 65.1 28.4 XIV* 1,750 68.2 29.6 XV* 550 70.6 31.4 From inspection of Example X*-XV*, it is clear that uncross-linked silicone polymers yield results which are generally much less satisfactory.
Altho~gh this invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various charges and modifications may be made which clearly fall within the scope of the invention.
CGS79546. PTIJ
5MEMBRANE PROCESS F`OR TP~EATING A
M XTURE CQNTAININIJ DEWAXED OIL
AND DEWAXING SOLVENT
D#79,546 10FIELD OF THE INVENTIO~
This invention relat~s to a procPss for tr~ating a charge containing dewaxing solvent and dewaxed oil. More particularly it relates to use of membrane technology to separate dewaxing solvent from dewaxed oil.
BACKGROUND OF THE INVENTION
As is well known to those skilled in the art, hydrocarbon stocks used for the preparation of lubricating oil contain undesirable components which are removed during processing to permit attainment of a product which is characterized by desired properties. Typically a charge stock is subjected inter alia to a dewaxing operation which decreases the wax content and desirably lowers the pour point and the cloud point of the lubricating oil stock.
Dewaxing may be effected by mixing a dewaxing solvent, such as methyl ethyl ketone or methyl isobutyl ketone, optionally in the presence of a hydrocarbon such as toluene or ~ylene, with the charge oil and cooling the mixture below the desired pour point, typically to minus 5F~minus 20F, say minus 10F, at which point wax precipitates. The wax is filtered; and the dewaxed oil - dewaxing solvent mixture is recovered.
CG579546 . PIN
03/06~91 This rPcovered mix~ure has classically been flashed to recover solvent-free lubricating oil stock and solvent which is free of lubricating oil.
Those sXilled in the art have attempted to improve the economics of this process by utilizing membrane technology to separate dewaxing solvent from dewaxed oil.
Illustrative of such prior art attempts may be the following:
USP 4,985,138 to Pasternak discloses a cross-linked polyimine membrane.
European Patent Specification 0 220 753 Al to Bitter et al discloses use of a halogen-substituted silicone membrane.
USP 4,678,555 to Wernick discloses use of cellulose acetate membranes.
European Patent Specification 0 125 907 A1 to Wight discloses use of a polyimide membrane containing -CO-N0-linkages.
USP 4,617,126 to Funk et al discloses use of a polysulfone membrane.
Additional background may be obtained from the references set forth in these patents.
It is an object of this invention to provide a process for treating a charge containing dewaxing solvent and dewaxed oil. Other objects~ will be apparent to those skilled in the art.
CGS79546 . P~N
STATEMENT O _THE INV~TION
In accordance with certain of the aspects, this lnvention is directed to a process for treating a charge containing dewaxing solvent and dewaxed oil which comprises passing said charge containing dewaxing solvent and dewaxed oil into con~act wit~l, as separating membrane, a non-porous elastomer separating polysiloxane membrane layer 10 which has been cross-linked with, as ~ cross-linXing agent, (i) a polyisocyanate or (ii) a poly(carbonyl chloride) or (iii) a silane R4_a Si (A~ a wherein A is -OH, -NH2 -OR, or -OOCR, a is 2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group; 5 maintaining a pressure drop across said membrane ther~by forming a high pressure retentate containing increased oontent of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of 2S said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of ~0 said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane thereby maintaining said charge de~axing solvent and dewaxed oil and said retentate in liquid phase;
CGS~DS~6 . P~N
03/06/f~l _ 3 _ recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and recovering said rletentate containing increased content of dewaxed oi.l and decreased content of dewaxing solvent.
DESCRIPTION OF THF INVENTION
The lube oil stocks which may be treated by dewaxing may include distillate stocks, de~sphalted oils, raffinates from solvent extraction of distillate, hydrotreated oils, hydrocracked distillates, etc. typically ranging in viscosity at 100F from about 30 SUS to 4000 SUS. Typically such a charge may be characterized by the following:
TABLE
ProPertv Ranqe Preferred Typical ibp F 590-goo 600-800 675 50% bp F 725-1100 800-900 850 90% bp F 800-1350 850-950 920 Viscosity SUS/100 F35-3500 40-100 54.63 60 F50-10,000 100-400 348.7 API Gravity20-30 22-29 25.8 Sp. Gr 15C/15C 0.870-0.895 0.880-0.890 0.890 Pour Poi~t F90-125 95-110 95+
Flash Point F 360-600 385-560 460 Refractive Index @ 70C1.4720-1.49401.4755-1.4920 1.4840 CGS7a5~6 . PTN
03/06/9~ _ 4 --This waxy oil charge ~100 volumes) is mixed with 100-1000 volumes, preferably 200-~,00 volumes, say 200 volumes (depending on the viscosity gracle and wax content of the feedstock) of ketone dewaxing solvent - such as acetone or preferably methyl ethyl ketone or methyl isobutyl ketone preferably diluted with a hydrocarbon solvent to produce dewaxing s~lvent. In a preferred embodiment, there may be added to 100 volumes of waxy oil charge, dewa~ing solvent 100 -- IS'D
~ 3~) containin~_56-~ volumes of ketone such as methyl ethyl ketone lc~o-- ~ o P 1O~1L~I plus bO-~5 volumes of a hydrocarbon solvent such as toluene or xylene. The mixture is cooled to minus 5F-minus 20F, say minus 10F, during which cooling, solid wax precipitates from the waxy oil charge. Typically a mid~continent distillate may be cooled to minus lO~F to obtain a 0F pour point 100 neutral oil. Wax is filtered in a rotary vacuum filter to yield a dewaxed oil filtrate.
In accordance with practice of the process of this invention, this filtrate, containing dewaxing solvent and dewaxed oil, is passed into contact with, as a separation membrane, a non-porous separating elastomer membrane layer.
THE MEMBRANE ASSEMBLY
Practice of the process of this invention may be carried out by use of a composite structure which in one preferred embodiment may include (i) a carrier layer which provides mechanical strength, (ii) a porous support layer, and (iii) a separating elastomer membrane layer across which separation occurs.
The composlte structure of this invention includes a multi-layer assembly which in the preferred CGS79546 . PTN
embodiment preferably includes a porous carrier layer which provides mechanical strength and support to the assemblyn THE CARRIER I~YER
This carrier layer, when used, is characterized by its high degree of porosity and mechanical strength. It may be fibrous or non-fibrous, woven or non-wovenO In the preferred embodiment, the carrier layer may be a porous, flexible, woven fibrous polyester. A typical polyester carrier layer may be formulated of non-woven, thermally-bonded strands.
THE POROUS SUPPORT LAYER
The porous support layer (typically an ultrafiltration membrane) which may be used in practice of this invention is preferably formed of polyacrylonitrile polymer.
Typically the polyacrylonitrile may be of thickness of 40-80 microns, say 50 microns and is preferably characterized by a pore size of less than about 500A and typically about 200A.
This corresponds to a molecular weight cut off of less than about 50,000, typically about 40,000.
THE SEPARATING LAYER
The separating layer which permits attainment of separation in accordance with the process of this invention includes a non-porous elastomer film or membrane of thickness 1-5 microns, say about 1.5 microns of a polysiloxane polymer of molecular weight Mn of about 550-150,000, preferably 550-4200, more preferably say about 1,750 (prior to cross-linking), which is cross-linked with, as cross-linking agent, (i) a polyiso-cyanate, or (ii~ a poly(carbonyl chloride) or (iii) R4~ Si(A)a CGS79546. PTN
wherein A is -OH, -H~2, OR~ or -OOCR, a is 2, 3, or 4, and R
is hydrogen, alkyl, aryl, cycloalkyl, alkaryl, or aralkyl.
The polysiloxanes which may be employed, as elastomer membranes, in practice of the process of this invention may include membranes of molecular weight Mnf 550-150,000, say 1,750 of halogen-free polysiloxanes which contain the repeating unit -si-o- and wherein the silicon atoms bear hydrogen or a hydrocarbon group. Preferably the repeating units are of the form --L sl o ~ R n In the above formula, R may be hydrogen or a hydrocarbon group selected from the group consisting of alkyl, aralkyl, cycloalkyl, aryl, and alkaryl, including such radicals when inertly substituted. Wh~n R i5 alkyl, it may typically be methyl, ethyl, n-propyl, iso-propyl, n-butyl, i-butyl, sec-butyl, amyl, octyl, decyl, octadecyl, etc. When R is aralkyl, it may typically be benzyl, beta-phenylethyl, etc. When R is cycloalkyl, it may typically be cyclohexyl, cycloheptyl, cyclooctyl, 2-methylcycloheptyl, 3-butylcyclohexyl, 3-methlcyclohexyl, etc. When R is aryl, it may typically be phenyl, naphthyl, etc. When R is alkaryl, it may typically be tolyl, xylyl, etc. R may be inertly substituted i.e. it may bear a non-reactive substituent such as alkyl, aryl, cycloalkyl, ether, etc. Typically inertly substituted R groups may include 2-ethoxyethyl, carboethoxymethyl, 4-methyl cyclohexyl, p-methylphenyl, p-ethylbenzyl, 3-ethyl-5-methylphenyll etc. The preferred R groups may be lower alkyl, i.e. Cl-C¦loalkyl, groups including e.g. methyl, ethyl, n-CGS79546.PTN
propyl, i-propyl, butyls, amyls, hexyls, octyls, decyls, etc.
R may preferably ba methyl~
The preferred of these halogen- ree poly-siloxanes are the di-silanol-terminated poly(dimethyl siloxanes) of lower molecular weight, typically 550-150,000, preferably 550-4200, more preferably, say 1,750. These polysiloxane elastomer membranes, which yield good Flux and Separation, may be characterized by the formula:
lCH3 r CH3 ~ IH3 HO - Si - O - L- Si - O - I _ Si - OH
CH2 CH3 ~ CH3 2Q wherein n is about 7-2000, say 24.
A preferred group of polysiloxanes may be poly-dimethyl siloxanes which are silanol terminated. Illustration polysiloxanes which may be employed may be those set forth in the Table which follows:
CGS79546~PTN
TABLE
Molecular Weight A Silanol terminated polydimet:hyl siloxane 550 B " ~ 1750 C " ~ 4200 D " ~ 58,000 E " " 110,000 F " ~ 150,000 G Acetoxy " " 3G,000 H Methoxy " " 27,000 I Ethoxy " " 950 J Carbinol " " 1250 K Aminopropyl 2500 dimethyl " "
It is a feature of the process of this invention that the sili~one membranes are cross-linked. In the case of the non-cyclic silicones, which bear reactive terminal groups typified by -OH or -NH2, they may be cross-linked by (i) a polyisocyanate, (ii) a poly(carbonyl chloride) or (iii) a silane R4-a Si (A)a wherein A is -OH, -NH2, -OR, or -OOCR, a is 2, 3, or 4, and R
may be as noted supra. The R groups need not be all the same.
It will be apparent that cross-linking is effected by reaction between the reactive terminal group of the non-cyclic silicone and the A group of the silane; and accordingly these groups whlch are to react should be different from each other. Preferably the silicone may be amino terminated, more preferably hydroxy terminated, and in the CGS79546.PTN
silane, A is preferably -OR or -OOCR. When the silane contains the moiety -OR or -OOCR, and the silicone is -OH terminated for example, the cross-linked polymer includes linkages of the type.
-- si--o--si It will be apparent that the silicone may be -OR
or -OOCR terminated, in which instance the silane may preferably contain an -OH moiety. It appears that no cross-linking may occur when the silicone is terminated by hydrogen.
When the silicone is a cyclic silicone, typified for example by decamethyl cyclopentasiloxane, it will be apparent that the molecule bears no terminal groups. In this instance, cross-linking is effected by breaking an Si O bond in the ring by reaction with the cross-linking agents.
It will be apparent that when A is -OR, the compound is an alkoxy silane; and when A is -OOCR, the compound is an acyloxy silane. When A is -NH2 OR -OH, the compound is an aminosilane qr a hydroxy silane.
Typical alkoxy silanes which may be employed may include:
CG5795~6 . P~N
TABLE
methyl triethoxy silane dimethyl diethoxy silane 5dimethyl dimethoxy silane ethyl trimethoxy silane phenyl triethoxy silane benzyl trimethoxy silane p-tolyl trimethoxy silane 101,2-dimethoxytetramethyl disilane tetramethoxy silane Typical acyloxy silanes ~hich may be employed may include:
TABLE
dimethyl diacetoxy silane methyl triacetoxy silane 20diethyl diacetoxy silane dipheny diacetoxy silane benzyl tri acetoxy silane p-tolyl tri acetoxy silane tetra acetoxy silane 251,2-di-acetoxytetramethyl disilane 1,2-dimethyltetra acetoxy disilane Mixed alkoxy, acyloxy silanes may be employed typified by:
~0 TABLE
dimethoxy diacetoxy silane methoxy triacetoxy silane cGs7as46 . PIN
Illustrative aminosilanes may include dimethyl diamino silane or dibutyl diaminosilane; illustrative hydroxy silanes may include diet}lyl di:hydroxy silane or methyl trihydroxy silane.
Typical polyisocyanat~s may include, the first listed being preferred:
TABI,E
toluene diisocyanate phenylene diisocyanate hexamethylene diisocyanate toluene tri-isocyanate Typical poly(carbonyl chlorides) may include, the first listed being preferred:
TABLE
~dipoyl dichloride isophthaloyl dichloride suberoyl dichloride Formation of the cross-linked elastomer silicone membrane may be carried out in a solution, in inert diluent-solvent (typified by a hydrocarbon such as commercial hexane) of 5-15, say lOw% of the non-halogenated polysiloxane plus 1-lOw%, say 4w% of cross-linking agent.
This solution may be solvent cast as a 0.5-4 mil, say 2 mil film onto a support layer (on a carrier layer) typically at say 25C. Thereafter it is cured at 110C-140C, say 125C for 10-20 minutes, say 15 minutes to form a film 1 5, say 1.5 thick.
CGS79546.PTN
T~IE_COMPOSITE MEMBRANE
It is a f eature oi- this invention that it may utilize a composite membrane wh:ich comprises (i) a carrier layer characterized by mechanica:L strength, for supporting a porous support layer and a separating layer ~ii) a porous support layer sush as a polyacrylonitrile membrane of 10-80 microns, and of molecular weight cut-off of 25,000-100,000, and (iii) as a non-porous separating layer a polysiloxane elastomer membrane which has been cross-linked with, as cross-linking agent, a polyisocyanate, or a poly(carbonyl chloride) or R4~ Si (A), wherein A is -OH, -NH~ -OR, or -OOCR, a is 2, 3, or 4, and R is alkyl, aryl, cycloalkyl, alkaryl, or aralkyl.
It is possible to utilize a spiral wound module which includes a non-porous separating layer membrane mounted on a porous support layer and a carrier layer, the assembly being typically folded and bonded or sealed along all the edges but an open edge - to form a bag-like unit which preferably has the separating layer on the outside. A cloth spacer, serving as the permeate or discharge channel is placed within the bag-like unit. The discharge channel projects from the open end of the unit.
There then placed on one face of the bag-like unit, adjacent to ~he separating layer, and coterminous therewith, a feed channel sheet - typically formed of a plastic net.
The so-formed assembly is wrapped around a preferably cylindrical conduit which bears a plurality of perforations in the wall - preferably in a linear array which is as long as the width of the bag-like unit. The projecting portion of the discharge channel of the bag-like unit is placed GGS79546 . PIN
03/06/9l -- 13 --over the perforations of ~he conduit; and the bag-like unit is wrapped around the conduit to form a spiral wound con-figuration. It will be apparent that, although only one feedchannel is present, the single feed channel in the wound assembly will be adjacent to two faces of ~he membrane layer~
The spiral wound configuratlon may be formed by wrapping the assembly around the conduit a pLurality of times to form a readily handleab]e unit. The unit is fitted within a shell (in manner comparable to a shell-and-t:ube heat exchanger) provided with an inlet at one end and an outlet at the other. A baffle-like seal between the inner surfaoe of the shell and the outer surface of the spiral~wound unit prevents fluid from bypassing the operative membrane system and insures that fluid enters the system principally at one end. The permeate passes from the feed channel, into conta~t with the separating layer and thence therethrough, into the permeate channel and thence therethrough to and through the perforations in the conduit through which it is withdrawn as net permeate.
In use of the spiral wound membrane, charge liquid is permitted to pass through the plastic net which serves as a feed channel and thence into contact with the non-porous separating membranes. The liquid which does not pass through the membranes is withdrawn as retentate. The liquid which permeates the membrane passes into the volume occupied by the permeate spacer and through this permeate channel to the perforations in the cylindrical conduit through which it is withdrawn from the system.
In another embodiment, it is possible to utilize the system of this invention as a tubular or hollow fibre. In this embodiment, the polyacrylonitrile porous support layer may be extruded as a fine tube with a wall thickness of typically 0.001-O.lmm. The extruded tubes are passed through a bath of CG579546 . E'T2i silicone which is cross-linked an~1 cured in situ. A bundle of these tubes is secured (wi~ an epoxy adhesive) at each end in a header; and the fibres are cut so that they are flush with the ends of the header. This tube bundle is mounted within a shell in a typical shell-and-tu~e assembly.
In operation, the charge liquid is admitted to the tube s~de and passes through the inside of the tubes and exits as retentate. During passage through the tubes, per~eate pas~es thrQugh the non~porous separating layer and permeate is collected in the shell side.
PRESSURE DRIVEN PROCESS
It is a feature of the non-porous cross-linked elastomer separating layer that it is found to be particularly effecti~e when used in a pressure driven piocess. In a pressure driven process, a charge liquid containinq a more permeable and a less permeable component is maintained in contact with a non~porous separating layer; and a pressure drop i5 maintained across that layer. A portion of the charge liquid dissolves into the membrane and diffuses therethrough.
The per~eate passes through the membrane and exits as a liquid.
In practice of the process of this invention, the charge containing dewaxing solvent and dewaxed oil in liquid phase typically at 20C-40C, say 25C may be passed into contact with the non-porous elastomer separating layer of the membrane of this învention. A pressure drop of about 500-1000 psi, say 800 psi is commonly maintained across the me~brane. The feed or charge side of the membran~ is at pressure sufficient ot drlve permeate across the membrane and commonly about 800 psig; and the permeate or discharge side of the membrane is at about atmospheric pressure. The feed is CG57~54 6 . P7N
03/06/9l -- 15 --passed over the surface (ca three inches in diameter in one embodiment) of the membrane at a rate (e.g. of about 1200 ml/min) which minimizes ~he possibility of concentration polarization.
The permeate which passes through the membrane includes increased content of dewaxing solvent and decreased content of dewaxed oil; and the retentate includes increased content of dewaxed oil and decreased content of dewaxing solvent.
Typically when the charge to the membrane contains(per 100 parts of oil) 100-1100, preferably 200-600 parts, say 200 parts of dewaxing solvent, the permeate may be found to typically contain about 96w% of dewaxing solvent.
Permeate is recovered in liquid phase.
Separation may typically be carried out at a flux of 20-40, say 37.1 kilograms per square meter per hour (kmh). Typically the membranes may have a rejection of more than 80% and commonly 70%-90%, say 89.7%.
Rejection % =
(Feed Concentration - Permeate Concentration) x 100 Feed Concentration.
Practice of the process of this invention will be apparent to those skilled in the art from the following examples wherein, as elsewhere in this specification, all percentages are percentages by weight unless otherwise stated.
CGS79546 . PIN
03~0b/91 -- 16 --D ~ RIPTI N OF SPEC~FIC EMBODI~ENTS
EXA~PLE I
In this Example, which represents the best mode of carrying out the process of this invention, the elastomer separating membrane is formed on the DUY-L brand (of Daicel Corp.) composite which includes as carrier layer the woven polyester backing described supra. The porous support layer is the commercially available polyacrylonitrile (PAN) having a 40,000 mole~ular weight cut off.
The solution of elastomer in commercial hexane containing ~i) 9w% disilanol-terminated poly dimethyl siloxane (m.w. 1750) and (ii) 4w~ 2,4-toluene diisocyanate is poured ~5 onto the porous support layer at 25C to coat a film of about 2 ~il thickness, followed by heat curing at 125C for 15 minutes.
This membrane (three inch diameter circle) is mounted in a standard cell. There is admitted to the cell and to the non-porous elastomer separating layer a charge con-taining one part by weight of dewaxed SNO-100 oil and 1 part by weight of methyl ethyl ketone and 1 part by weight of toluene.
Separation is carried out at room temperature of 25~C and a charge (and retentate) pressure of about 800 psig.
Feed is at 25C/800 psig at flow rate of 1200 ml/min.
Permeate pressure is atmosphexic. Selectivity is measured and reported as % Rejection which is calculated at 100 x (the quantity of dewaxed oil in the feed minus the quantity of dewaxed oil in the permeate) divided by the quantity of dewaxed oil in the feed. Clearly a higher Selectivity is desired, as this means that the retentate desirably contains less dewaxing CG579546 . P~N
03/06/9l -- 17 --solvent and the permeate desirably contains more solvent. Flux is measured as kilograms per square meter per hour (kmh).
In this ~xample, the Selectivity is 89.7%
rejection and the Flux is 37.1.
_XAMPLES II-V
In this series of Examples, the procedure o~
Example I is followed except that in Example II, the toluene diisocyanate is present in amount of 2%, in Examples III-IV the cross-linking agent is adipoyl dichloride (2w% and 4w%
respectively) and in Example V, no cross-linking agent is employed.
TABLE
Selectivity Flux Example % Re~ection (kmh~
I 89.7 37.1 II 87.4 36.8 III 84.2 39.1 IV 83.5 37.2 V* 68.2 29.6 * Conntrol Example EXAMPLES VI-Ix In this series of Examples, the procedure of Example I is followed except that the polysiloxane is decamethyl cyclopentasiloxane CG579546 . P~N
03/06~9~ -- 18 --(CH3~ Si - - Si ICH3~2 o o si - o -- si - o - si ICH3~2 ~CH3~2 ICH3~2 present as 5w% solution in commercial hexane which also contains 5w% of a multifunctional cross-linking agent as noted in the Table which follows:
TABLE
Example Cross-Linkinq Selectivit~ Flux Aqent (~Reiection) (kmh~
VI dimethyl diethoxy silane 77.4 29.7 VII methyl triethoxy silane 77.4 33.4 VIII dimethyl diacetoxy silane 82.5 34.0 IX* no cross-linking agent 77.4 30.6 From inspection of Examples I-IX*, it will be apparent that the technique of this invention permits attainment of results (in terms of Selectivity and Flux~ which are consistently higher than those attained when no cross-linking agent is employed. Best results appear to be attained in Example I using a linear disilanol terminated poly dimethyl siloxane which has been cross-linked with toluene diisocyanate.
,,, EXAMPLES X*-XV*
CGS795~ 6 . P~N
In this series of Ex,amples, a series of silanol-terminated polydimethyl siloxanes of different molecular weight (in lOw% hexane solution) were formed into similar elastomer membranes which were not chemically cross-linked.
TABLE
ExampleMolecular _lectivity Flux ~ gb~_ Reiection~ (kmh) X* 150,000 47.7 23.3 XI* 110,000 48.5 26.3 XII* 58,000 53.8 24.1 XIII* 4,200 65.1 28.4 XIV* 1,750 68.2 29.6 XV* 550 70.6 31.4 From inspection of Example X*-XV*, it is clear that uncross-linked silicone polymers yield results which are generally much less satisfactory.
Altho~gh this invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various charges and modifications may be made which clearly fall within the scope of the invention.
CGS79546. PTIJ
Claims (25)
1. The process for treating a charge containing dewaxing solvent and dewaxed oil which comprises passing said charge containing dewaxing solvent and dewaxed oil into contact with, as separating membrane, a non-porous elastomer separating polysiloxane membrane layer which has been cross-linked with, as cross-linking agent, (i) a polyisocyanate or (ii) a poly(carbonyl chloride) or (iii) a silane R4-a Si (A). wherein A is -OH, -NH2, -OR, or -OOCR, a is
2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group;
maintaining a pressure drop across said membrane thereby forming a high pressure retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane thereby maintaining said charge dewaxing solvent and dewaxed oil and said retentate in liquid phase;
CGS79546.PTN
recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and recovering said retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent.
CGS79546.PTN - 22 -2. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane, prior to cross-linking, has a molecular weight Mn of about 550-4200.
maintaining a pressure drop across said membrane thereby forming a high pressure retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane thereby maintaining said charge dewaxing solvent and dewaxed oil and said retentate in liquid phase;
CGS79546.PTN
recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and recovering said retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent.
CGS79546.PTN - 22 -2. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane, prior to cross-linking, has a molecular weight Mn of about 550-4200.
3. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane is a cyclic polysiloxane.
4. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane is a linear polysiloxane.
5. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane is a silanol-terminated linear polysiloxane.
6. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said polysiloxane is a silanol-terminated linear dimethyl siloxane of molecular weight Mn of 550-4200.
7. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is a polyisocyanate.
8. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is a toluene diisocyanate.
C5S79546.PTN
C5S79546.PTN
9. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is a poly(carbonyl chloride).
10. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is adipoyl dichloride.
11. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is R4-a Si (A)a wherein A is -OR or -OOCR, a is 2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group.
12. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is dimethyl diacetoxy silane.
13. The process for treating a charge containing dewaxing solvent and dewaxed oil as claimed in Claim 1 wherein said cross-linking agent is methyl triethoxy silane.
CGS79546.PTN
CGS79546.PTN
14. The process for treating a charge containing dewaxing solvent and dewaxed oil which comprises passing said charge containing dewaxing solvent and dewaxed oil into contact with, as separating membrane, a non-porous elastomer separating polysiloxane layer which has been cross-linked with a toluene diisocyanate cross-linking agent;
maintaining a pressure drop across said membrane thereby forming a high pressure retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane by thereby maintaining said charge dewaxing solvent and dewaxed oil and said retentate in liquid phase;
recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and CGS79S46 . PTN
recovering said retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent.
CG579546 . PIN
maintaining a pressure drop across said membrane thereby forming a high pressure retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent and a low pressure permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil;
maintaining the pressure on the low pressure discharge side of said membrane above the vapor pressure of said permeate thereby maintaining said permeate in liquid phase;
maintaining the pressure on the high pressure retentate side of said membrane above the vapor pressure of said charge containing dewaxing solvent and dewaxed oil and sufficient to drive permeate across said membrane by thereby maintaining said charge dewaxing solvent and dewaxed oil and said retentate in liquid phase;
recovering said permeate containing increased content of dewaxing solvent and decreased content of dewaxed oil; and CGS79S46 . PTN
recovering said retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent.
CG579546 . PIN
15. An elastomer membrane, characterized by the ability to effect separation of dewaxing solvent and dewaxed oil, which comprises a non-porous; elastomer membrane layer of a polysiloxane which has been cross-linked with as cross-linking agent, a polyisocyanate, (ii) a poly(carbonyl chloride), or (iii) a silane R4-a Si(A)a wherein A is -OH, -NH2, -OR, or -OOCR, a is 2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group.
16. A membrane as claimed in Claim 15 wherein said polysiloxane is a cyclic polysiloxane.
17. A membrane as claimed in Claim 15 wherein said polysiloxane is a linear polysiloxane.
18. A membrane as claimed in Claim 15 wherein said polysiloxane is a silanol-terminated linear polysiloxane.
19. A membrane as claimed in Claim 15 wherein said polysiloxane is a silanol-terminated linear dimethyl siloxane of molecular weight Mn of 550-4200.
20. A membrane as claimed in Claim 15 wherein said polysiloxane said cross-linking agent is a polyisocyanate.
21. A membrane as claimed in Claim 15 wherein said cross-linking agent is a toluene diisocyanate.
22. A membrane as claimed in Claim 15 wherein said cross-linking agent is a poly(carbonyl chloride).
CGS79546 . PTN
CGS79546 . PTN
23. A membrane as claimed in C.aim 15 wherein said cross-linking agent is adipoyl dichloride.
24. A membrane as; claimed in Claim 15 wherein said cross-linking agent is R4-a Si(A) wherein A is -OR or -OOCR, a is 2, 3, or 4, and R is hydrogen or an alkyl, aralkyl, cycloalkyl, aryl, or alkaryl group.
25. A membrane as claimed in Claim 15 wherein said cross-linking agent is dimethyl diacetoxy silane.
CGS79546 . PTN
CGS79546 . PTN
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/692,890 US5102551A (en) | 1991-04-29 | 1991-04-29 | Membrane process for treating a mixture containing dewaxed oil and dewaxing solvent |
| US07/692,890 | 1991-04-29 |
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| Publication Number | Publication Date |
|---|---|
| CA2052550A1 true CA2052550A1 (en) | 1992-10-30 |
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ID=24782468
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002052550A Abandoned CA2052550A1 (en) | 1991-04-29 | 1991-10-01 | Membrane process for treating a mixture containing dewaxed oil and dewaxing solvent |
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|---|---|
| US (1) | US5102551A (en) |
| EP (1) | EP0511839A3 (en) |
| JP (1) | JPH05156264A (en) |
| CA (1) | CA2052550A1 (en) |
Families Citing this family (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5264166A (en) * | 1993-04-23 | 1993-11-23 | W. R. Grace & Co.-Conn. | Polyimide membrane for separation of solvents from lube oil |
| GB2389975B (en) * | 2001-03-19 | 2005-08-24 | Integrated Power Components In | A repair device for fixing a malfunctioning shunt in a decoration light string |
| US7051811B2 (en) | 2001-04-24 | 2006-05-30 | Shell Oil Company | In situ thermal processing through an open wellbore in an oil shale formation |
| WO2003036038A2 (en) | 2001-10-24 | 2003-05-01 | Shell Internationale Research Maatschappij B.V. | In situ thermal processing of a hydrocarbon containing formation via backproducing through a heater well |
| GB0229423D0 (en) | 2002-12-18 | 2003-01-22 | Avecia Ltd | Process |
| EP1680485A1 (en) * | 2003-11-04 | 2006-07-19 | Shell Internationale Researchmaatschappij B.V. | Process for upgrading a liquid hydrocarbon stream with a non-porous or nano-filtration membrane |
| US20090012342A1 (en) * | 2004-10-11 | 2009-01-08 | Johannes Leendert Den Boestert | Process to prepare a haze free base oil |
| EP1941001A2 (en) | 2005-10-24 | 2008-07-09 | Shell Internationale Research Maatschappij B.V. | Methods of producing alkylated hydrocarbons from a liquid produced from an in situ heat treatment |
| AU2007240353B2 (en) | 2006-04-21 | 2011-06-02 | Shell Internationale Research Maatschappij B.V. | Heating of multiple layers in a hydrocarbon-containing formation |
| GB2441132A (en) | 2006-06-28 | 2008-02-27 | Pronova Biocare As | Process for reducing the free fatty acid content of natural oils using a selectively permeable membrane |
| CA2667274A1 (en) | 2006-10-20 | 2008-05-02 | Shell Internationale Research Maatschappij B.V. | Systems and processes for use in treating subsurface formations |
| ES2500466T3 (en) * | 2006-12-20 | 2014-09-30 | Shell Internationale Research Maatschappij B.V. | Procedure for removing poly (propylene oxide) from propylene oxide by membrane separation |
| AR067244A1 (en) | 2007-03-27 | 2009-10-07 | Shell Int Research | METHOD FOR REDUCING THE CONTENT OF NATURAL GAS CONDENSATION AND THE NATURAL GAS PROCESSING PLANT |
| WO2008131173A1 (en) | 2007-04-20 | 2008-10-30 | Shell Oil Company | Heating systems for heating subsurface formations |
| US8146669B2 (en) | 2007-10-19 | 2012-04-03 | Shell Oil Company | Multi-step heater deployment in a subsurface formation |
| WO2012076532A1 (en) | 2010-12-08 | 2012-06-14 | Shell Internationale Research Maatschappij B.V. | Process for purifying aryl group containing carbonates |
| WO2012076519A1 (en) | 2010-12-08 | 2012-06-14 | Shell Internationale Research Maatschappij B.V. | Process for purifying dialkyl carbonate |
| US8895792B2 (en) * | 2012-12-28 | 2014-11-25 | Shell Oil Company | Process for the preparation of an olefinic product comprising ethylene and/or propylene |
| US9375685B2 (en) * | 2014-03-28 | 2016-06-28 | L'Air Liquide Société Anonyme Pour L'Étude Et L'Exploitation Des Procedes Georges Claude | Membrane for the separation of a mixture of a polar fluid and a non-polar fluid and methods for use thereof |
| US20180133663A1 (en) * | 2016-11-17 | 2018-05-17 | Uop Llc | High selectivity chemically cross-linked rubbery membranes and their use for separations |
| CN109694744B (en) * | 2017-10-24 | 2022-03-15 | 中国石油化工股份有限公司 | Method for recovering dewaxing solvent for lube-oil feedstock and method for dewaxing lube-oil feedstock |
| CN109694724B (en) * | 2017-10-24 | 2022-03-15 | 中国石油化工股份有限公司 | Method for recovering dewaxing solvent for lube-oil feedstock and method for dewaxing lube-oil feedstock |
| JP2022502249A (en) | 2018-10-01 | 2022-01-11 | シエル・インターナシヨネイル・リサーチ・マーチヤツピイ・ベー・ウイShell Internationale Research Maatschappij Besloten Vennootshap | Method for removing catalytic fine powder by nanofiltration |
| CN114450478A (en) | 2019-09-25 | 2022-05-06 | 国际壳牌研究有限公司 | Method for reducing injector deposits |
| BR112022008630A2 (en) | 2019-11-20 | 2022-07-19 | Shell Int Research | PROCESS TO REMOVE POLY(PROPYLENE OXIDE) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4167612A (en) * | 1978-06-19 | 1979-09-11 | Wm. T. Burnett & Co., Inc. | Flexible polyurethane foams having low resistance to air flow and method for preparation |
| JPS5973005A (en) * | 1982-09-16 | 1984-04-25 | モンサント・コンパニ− | Multi-component membrane for separating gas |
| IN167504B (en) * | 1984-03-12 | 1990-11-10 | Exxon Research Engineering Co | |
| US4602922A (en) * | 1984-11-09 | 1986-07-29 | Research Foundation Of State University Of New York | Method of making membranes for gas separation and the composite membranes |
| GB8619278D0 (en) * | 1986-08-07 | 1986-09-17 | Shell Int Research | Separating fluid feed mixture |
| CN1045770A (en) * | 1989-03-18 | 1990-10-03 | 王英 | With the system of film distillation technical point from concentrated ammonium acetate and ammonium hydroxide |
| US4985138A (en) * | 1989-11-08 | 1991-01-15 | Texaco Inc. | Process for treating a charge containing dewaxing solvent and dewaxed oil |
| US5146038A (en) * | 1990-07-16 | 1992-09-08 | Texaco Inc. | Process for treating a mixture containing dewaxed oil and dewaxing solvent |
-
1991
- 1991-04-29 US US07/692,890 patent/US5102551A/en not_active Expired - Fee Related
- 1991-10-01 CA CA002052550A patent/CA2052550A1/en not_active Abandoned
-
1992
- 1992-04-29 EP EP19920303842 patent/EP0511839A3/en not_active Withdrawn
- 1992-04-30 JP JP4135685A patent/JPH05156264A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| EP0511839A3 (en) | 1993-01-07 |
| US5102551A (en) | 1992-04-07 |
| EP0511839A2 (en) | 1992-11-04 |
| JPH05156264A (en) | 1993-06-22 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |