CA2202946A1 - Sulfobetaine-containing polymers and their utility as calcium carbonate scale inhibitors - Google Patents
Sulfobetaine-containing polymers and their utility as calcium carbonate scale inhibitorsInfo
- Publication number
- CA2202946A1 CA2202946A1 CA002202946A CA2202946A CA2202946A1 CA 2202946 A1 CA2202946 A1 CA 2202946A1 CA 002202946 A CA002202946 A CA 002202946A CA 2202946 A CA2202946 A CA 2202946A CA 2202946 A1 CA2202946 A1 CA 2202946A1
- Authority
- CA
- Canada
- Prior art keywords
- copolymer
- groups
- diallyl
- water
- alkyl
- 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
Classifications
-
- 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
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/0605—Polycondensates containing five-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms
- C08G73/0611—Polycondensates containing five-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms with only one nitrogen atom in the ring, e.g. polypyrroles
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
- C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
- C02F5/12—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing nitrogen
Abstract
The invention is a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of an N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine of the formula:
wherein R is selected from the group consisting of alkyl and aryl groups, and R1is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The invention is also a method of inhibiting the precipitation and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of a betaine of the formula:
wherein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A preferred polymer is a water-soluble copolymer of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
wherein R is selected from the group consisting of alkyl and aryl groups, and R1is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The invention is also a method of inhibiting the precipitation and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of a betaine of the formula:
wherein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A preferred polymer is a water-soluble copolymer of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
Description
Field of the Invention The invention is a water-soluble N,N-diallyl-N-alkyl-N-(sulfoaL~cyl) ammonium betaine co~ h-g copolymer, wherein said copolymer.is formed from the polymerization of an N,N-diallyl-N-aLkyl-N-(sulfoalkyl) ~mmonium betaine of the formula:
H2C~ ~CH2 CH fH
CH~) 5H2 /N\
R Rl--SO3 wherein R is selected from the group consisting of aLkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The invention is also a method of inhibiting the precipitation and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed I ~ t'rom the polymerization of a betaine of the formula:
H~C ~ .~CH2 CH fH
~ 5 / \
R Rl--SO3 wherein R is selected from the group con~i~tinE of alkyl and aryl groups, and R
is selected fr~n the group con~ nE of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A plefell~d polymer is a water-soluble copolymer of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
k.g.round of the Invention The utilization of water which contains certain inorganic h~ ilies, and the production and processing of crude oil water mixtures co..~ .E such hl~ ;lies, is 10 plagued by the precipitation of these impurities with subsequent scale formation. In the case of water which contains these cont~min~nt.c the harmful effects of scale formation are generally confined to the reduction of the capacity or bore of receptacles and conduits emploved to store and convey the cont~min~te~ water. In the case of conduits, the impedance of flow is an obvious consequence. However, a number of equally I ~ consequential problems are realized in specific utilizations of cont~min~ted water. For e~;ample scale formed upon the surfaces of storage vessels and conveying lines for process water may break loose and these large masses of deposit are entrained in and con~ eyed by the process water to damage and clog equipment through which the water is passed. e.~.~ tubes. valves. filters and screens. In addition, these crystalline deposits may '() appear in. and detract from. the final product which is derived from the process, e.g., paper formed from an aqueous suspension of pulp. Furthermore, when the cont~min:~t~cl water is involved in a heat exchange process, as either the "hot" or "cold" medium, scale will be formed upon the heat exchange surfaces which are contacted by the water. Such scale formation forms an insulating or thermal opacifying barrier which impairs heat transfer efficiency as well as impeding flow through the system.
Scale can also be formed during ~v~o.dLi~e cooling, when the level of dissolved ionic species will increase as water from the solution evaporates. Scale will then form 5 when the concentration of a salt exceeds its solubility under the conditions experienced.
This scaling process is typically observed in evaporative cooling towers, and the buildup of scale on the tower fill can cause a large decrease in tower efficiency.
While calcium sulfate and calcium carbonate are primary contributors to scale formation, other salts of ~lk~line-earth metals and the all..l,;llll... silicates are also 10 offenders. e.g., magnesium carbonate, barium sulfate, the alllminum silicates provided by silts of the bentonitic, illitic, and kaolinitic types among others. When phosphate anions are present. either naturally or added to the system, calcium phosphate scaling can also be significant.
Many other industrial waters, while not being scale forrning, tend to be corrosive.
1~ Such waters. when in contact with a variety of metal surfaces such as ferrous metals, aluminum. copper and its alloys. tend to corrode one or more of such metals or alloys. A
v ariety of compounds have been suggested to alleviate these problems. Such materials are low molecular weight polyacrylic acid polymers. Corrosive waters of this type are usually acidic in pH and are commonly found in closed recirculating systems.
'0 Numerous compounds have been added to these industrial waters in an attempt to prevent or reduce scale and corrosion. One such class of materials are the well known organophosphonates which are illustrated by the compounds hydroxyethylidene diphosphonic acid (HEDP) and phosphonobutane tricarboxylic acid (PBTC). Another group of active scale and corrosion inhibitors are the monoso(~ m ~h~sphinicobis (succinic acids~ which are described in U. S. Pat. No. 4,088,678. Fur~er, N, N-bis(phosphono methyl) derivative compounds in combination with homo or copolymers - are disclosed for inhibition of calcium c~bu.~ deposition in U. S. Patent No.
5 5,087,376.
Most industrial waters contain ~Ik~line earth metal cations, such as calcium, barium, magnesium, etc. and several anions such as bicarbonate, c~arbonate, sulfate, oxalate, phosphate, silicate, fluoride, etc. When combinations of these anions and cations are present in concentrations which exceed the solubility of their reaction products, 10 precipitates form until these product solubility concentrations are no longer exceeded.
For example, when the concentrations of calcium ion and carbonate ion exceed the solubility of the calcium carbonate reaction products, a solid phase of calcium carbonate u ill fonn. Calcium carbonate is the most common form of scale in many industrial processes .
1~ Solubility product concentrations are exceeded for various reasons, such as partial ev aporation of the water phase, chan~e in pH, pressure or temperature, and the introduction of additional ions which forrn insoluble compounds with the ions already present in the solution.
As these reaction products precipitate on surfaces of the water carrying system, ~() the! form scale or deposits. This accumulation prevents effective heat transfer, interferes w ith fluid flow, facilitates corrosive processes and harbors bacteria. This scale is an e~;pensive problem in many industrial water systems causing delays and shutdowns for cleaning and removal.
Scale deposits are generated and ~-~tenAffl-principaliyt~y -means of crystal growth;
and various a~ploaches to reducin~scale clevelopment have accordingly included inhibltion of crystal growth, modification of crystal growth and dispersion of the scale-forming rninerals.
Various polymeric treatments for scale controi exist Among them are the use of anionic co- or ter- polymers of N-vinyl-2-pyrrolidone or vinyl amide, as disclosed in U.S.
Patent No. 4,913,824; the use of maleic anhydride/4~ r ammonium-type polymers as disclosed in U.S. Patent No. 5,015,390 and the use of co- and ter-polymers of(meth)acrylic acid and sulfoalkyl(meth) acrylamide as disclosed in U.S. Patent No.
4~801,388.
Co-polymerization of N-(4-sulfoalkyl)N-methyldiallyl ammoniurn betaines with N-vinyl pyrrolidone or acrylamide to obtain a water-soluble co-polymer has been disclosed in U. S. Patent No. 4,585,846.
However, there is still a need for a polymeric treatment to more efficiently combat I 5 scale. The polymers described herein accomplish this purpose.
Summary of the Invention The invention is a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) amrnonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of an N.N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine ofthe formula:
H2C~ - ,~CH2 i .
CH ICH
CH~)/ H2 / \
R Rl--SO3 wherein R is selected from the group con.ci~ting of aLkyl and aryl groups, and Ris selected from the group comi~ting of alkyl groups, aryl groups, and alkylarylgroups, and an anionic monomer.
The invention is also a method of inhibiting the plecipi~lion and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-10 (sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polvmerization of a betaine of the formula:
H~C~ ~CH2 CH fH
CH~ (3 5H2 / \
R Rl--SO3 ~herein R is selected from the group consisting of alkyl and aryl groups, and R~is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A pl~;rell~d polyrner is a water-soluble copoly ner of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine and acrylic acid.
Descr~ption of the Invention The invention is a water-soluble N,N-diallyl-N-allcyl-N-(sulfoalkyl) ammonium 5 betaine cont~ining copolymer, wherein said copolymer is formed from the polymerization of an N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine of the formula:
H2C~ ~CH2 CH fH
~ 5 /N\
R Rl--SO3 wherein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The copolymer may have R selected from the group consisting of alkyl groups ha~ing about I to 20 carbon atoms and R~ selected from the group consisting of C~-C6 ~ ~ all~yl groups, phenyl groups. naphthyl groups~ benzyl groups, and naphthylmethyl groups.
The copolymer may be formed from an anionic monomer which is selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, ~ inyl sulfonic acid, styrene sulfonate. sodium acrylamido methyl propane sulfonic acid, and maleic acid.
Preferably, the water-soluble copolyrner is of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
The molecular weight of the copolymer may be from about 3,000 to about 100,000. Preferably, the molecular weight is from about 4,000 to about 50,000. Most preferably, the molecular weight is from about 4,000 to about 20,000.
The copolymer may have a molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid of from 0.5 :99.5 to 30:70. Preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl).ammonium betaine to acrylic acid is from 1:99 to 20:80. Most preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine to acrylic acid is from 3:97 to 10:90.
The invention is also a method of inhibiting the precipitation and deposition ofscale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed I ~ from the polymerization of a betaine of the formula:
H,C~ ~CH2 CH fH
CH, (3 5H2 / \
R R~--SO3 ~herein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups~
and an anionic monomer.
The anionic monomer may be selected ~rom the~ up consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, vinyl sulfonic acid, styrene sulfonate, sodium acrylamido methyl propane sulfonic acid, and maleic acid. R may be selected 5 from the group consisting of alkyl groups having about 1 to 20 carbon atoms and Rl may be selected from the group con~isting of Cl -C~ alkyl groups, phenyl groups, naphthyl groups, benzyl groups, and naphthylmethyl groups.
Preferably, the water-soluble copolymer is composed of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
10The molecular weight of the copolymer may be from about 3,000 to about 100.000. Preferably, the molecular weight of the copolymer may be from about 4,000 to about 50,000. Most preferably, the molecular weight of the copolymer may be from about 4.000 to about 20~000.
The molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to 15acrylic acid may be from 0.5:99.5 to 30:70. Preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine to acrylic acid is from 1:99 to 20:80. Most preferably~ the molar ratio of N~N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 3:97 to 10:90.
The water-soluble copolymer may be added to the industrial cooling water in an '0 amount of about 0.1 ppm to about 300 ppm. Preferably, the water-soluble copolymer may be added to the industrial cooling water in an amount of about 1 ppm to about 100 ppm. Most preferably. the water-soluble copolymer may be added to the industrial cooling water in an amount of about 5 ppm to about 50 ppm.
In the practice of this invention, a water-soluble anionic polymer and a phosphorous-co~ g scale inhibitor may also be added to the cooling water. The anionic polymer may be a sulfon~ted polyacrylate and the phosphorous-co."~ il-g scale inhibitor may be selected from the group conci~tin~ of 1-hydroxy ethylidene -1, 1-5 diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ammonium monophosphate, and aminotris(methylene phosphonic acid). Preferably, about 1 to about 300 ppm of the water-soluble copolymer of N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine and acrylic acid, from about 1 to about 50 ppm of the water-soluble anionic polymer and from about 1 to about 50 ppm of the phosphorous-cont~ining scale 10 inhibitor may be added to the cooling water.
The term scale as used herein refers to calcium carb~nate or calcium phosphate scale.
In addition to acrylic acid, other co-monomers can be polymerized with N,N-diallvl-N-alkyl-N~(sulfoalkyl) ammonium betaine such as methacrylic acid, maleic acid, 1~ maleic anhydride, itaconic acid, vinyl sulfonic acid, styrene sulfonate, sodium acrylamidomethylpropane sulfonic acid (AMPS) or nonionic monomers such as acrylamide. N-substituted acrylamides, vinyl acetate, or acrylate esters. As used herein, lhe term co-polymers is meant to encompass polymers formed from two or more different monomers .
~() The polymer can be applied to the system at any convenient point. For example, the proper amount of the polymer solution can be added either periodically or continuously to the make-up water.
The copolymers Qf this invention can be used in conj~l,~ion with other cooling - tower treating agents such as other scale inhibitors, corrosion inhibitors, and biocides.
As used herein, ~e term aL~cyl groups ~nco~ Acses those groups cont~ining oxygen fianctionalities such as ether, polyethers and alcohols.
The following examples are presented to describe pr~;r~ ;d embo.liment.c and utilities of the invention and are not meant to limit the invention unless otherwise stated in the claims appended hereto.
Example 1 - - -The following formulation was used for synthesis of the diallyl, methyltaurine monomer from N-methyltaurine, or sodium salt (formula: Me-NH-CH2CH2SO3Na) and allyl chloride. The systematic name for this monomer is: N,N-diallyl-N-methyl-N-(2-sulfoethyl)ammoniu n betaine. : ;
Diallyl Taurine F~rmulation .Fv. ~
Çhçnical W~t %MoleRatio N-Me~yl~unne 60.4 % 1.0 NaSalt (35% ac~ves) AllylChlonde 30.2 % 3.0 NaOH(50 %) 9.4 % 0.9 100.0%
The 35 % aqueous solution of N-methyltaurine sodiurn salt at pH 12 (138 g) was placed in a glass liner inside a stainless steel ~le~ reactor, and the first aliquot of ally chloride (35.8 g, 1.5 eq) was added. The reactor was sealed, stirring begun, and the mixture was heated to 80 - 85~ C at a pressure of 40 - 80 psi. After stirring for 0.5 hr, NaOH was injected to raise the pH to 11. Additional allyl chloride was added at 1 hour, 20 and more NaOH was introduced at 1.5 hr to increase the pH to 11. A final addition of N~OH was done at 2.0 hr., and the reaction was ended after 2.5 hr.
The reactor was cooled to give 220 g of crude product with pH near 6. Dl water (200 g) was added to the crude product~ and the solution was concentrated to give appro~imately 120 g of residue consisting of the desired monomer, NaCl, and some ~5 water. Dl water (~45 g) was added to give 165 g of solution cont~ining 40 wt % diallyl methyltaurine, plus NaCI. The solution was cooled, and precipitated NaCl was filtered of'f. The product was >90 % the desired diallyl methyltaurine, according to 13C NMR.
The remaining material was mono-allyl methyltaurine.
Low molecular-weight polymers of acrylic acid (AA) and diallyl, m~lhyl~u~ e (DAMT) were prepared by solution polymerization using redox initiators such as sodium bisulfite and ammonium persulfate. A semi-batch polym~n7~tion method was used whereby monomer and initiator solutions were fed into a reactor over the course of 1 5 hour.
Example 2 In a typical stress solubility experiment, 200 ml of a test solution col-t~ h-g 800 ppm CaCI2 and 800 ppm NaHCO3 (each as CaCO3) and the desired amount of inhibitor was placed in a 250 ml Erlenrneyer flask. A sample of the test solution was collected 10 prior to heating and sent for atomic absorption analysis in order to obtain a very accurate initial calcium concentration value.
The sample was then placed in the water bath and the solution is allowed to reach the water bath temperature. The pH electrode and NaOH line of an auto-titrator were then placed in the solution and the sample titrated to pH 9.00. Typically, the auto-] ~ titration system was set to the delayed stop mode so that the desired pH is approachedslowl~ and is not overshot. The time at which the sample reaches pH 9.00 was noted, the pH electrode and NaOH line rinsed. and the next sample was titrated to pH 9.00. The pH
- of the titrated solutions was checked and occasionally adjusted to pH 9.0 during the experiment.
'0 Two hours after a sarnple was first titrated to pH 9.00, the solution is removed from the water bath, 5 ml of the solution was removed using a syringe and filtered into a weighing boat. A portion of this sample, either 1.0, 2.0 or 3.0 ml, was then placed in a B.U.N. tube for Atomic Absorption (AA) analysis. The amount of solution was selected to give less than 60 ppm calcium (as calcium ion) when diluted to 25 ml. The samples were then analyzed by AA. - -The results from the diluted AA analysis sample, normally reported as ppmcalcium, were then used to calculate the concentration of soluble calciurn in the heated S test solution.
This experimental procedure was utilized to obtain the results detailed in Table I.
Lower ppm values for calcium precipitate indicate better scale inhibition. Table I results show that at above a 150 ppm treat rate, the polymers of the instant invention show performance as a calcium carbonate scale inhibitor which is superior to that of 10 poly(acrylic acid).
TABLE I
- Acrylate Pobmer Results - InhibitorInhibitor Concentration ~ Calcium ~r~c;l.ilate (ppm as actives) (ppm as CaCO3 ) p(AA)' 5 620 lO0 470 200 ~470 250 ~ 400 p(AA/DAMT)i 5 690 5 I = poly(acrvlic acid), 5,000 MW
' = 5 ppm 1-phosphono butane 1.~ 4 tricarboxylic acid added to each test solution = 90 10 mole ratio of poly (acrvlic acid diallyl methvltaurine) 6,000 MW
FY~ ple 3 The experimental procedure ~escribed in Example 2 was utili~d to obtain the results detailed in Table II.
- TABLE II
Sulfonated Polymers Results Inhibitor Concentration Calcium Precipitate Inhibitor (ppm as actives) (ppm as CaC03) p(AA/AMPS)I 5 800 p(AA/DADMAC) 5 795 p(AA/DAMT)3 5 790 I = 90/10 mole ratio of acrylic acid to sodium AMPS 6,000 MW
= 90/10 mole ratio of acrvlic acid to diallyl dimethyl ammonium chloride 4,900 MW
3 = 90/10 mole ratio of poly (acrylic acid/diallyl methyltaurine) 6,000 MW
l ( I Since lower values for the arnount of calcium precipitate were obtained for p( .~A!DAMT) than for the other polymers tested, the superiority of polymers of the instant invention is demonstrated. In addition, these results show that the sulfobetaine structure (RlN -CH,-CH~-SO3-) in the DAMT polymers is needed for best performance.
The polymers c~ either a sulfonate or a cationic monomer (DADMAC) did not - perforrn as well.~
. _ _ ~. _ .
F,Yample 4 S A hardness soluti~n of calciurn and m~ in a2:11Ca:Mg ratio and an ~lk~line solution of sodium carbonate/sodium bicarbonate buffered at pH 10 were simultaneously added to 200 rnL of an inhibitor test solution. The pH of the inhibitor test solution was adjusted-to bet~ZveeI}-7.~ ~ ium ~ cçip*~tion was detected by turbidity using a Brinkman PC-800 Colorimeter (420 nm wavelength). The hardness solution was prepared by adding 3.80 g calciurn acetate and 2.57 g m~gnesium acetate tetrahydrate to distilled water (100 rnL; total volurne~ The ~ snh~tion was prepared bv adding 2.01 g sodium bicarbonate and 1.27 g sodium carbonate to distilled water (100 mL total volume). A Masterflex pump delivered the hardness and aLkaline solutions at '.0 mL/min to the magnetically stirred-test solution.~ ~11 solutions~were aqueous and maintained at a constant temperature of 45~C. The titraeion endpoint, expressed as the ma~imum calciurn concentration (as calcium carbonate) before the onset of turbidity, was calculated from the elapsed time to a turbidity inflection on a strip chart recorder.
The procedure above was utilized to obtain the results ~f Table III. The p( AA/DAMT) showed superior performance to PBTC or p(AA), as illustrated by the '() lar~er endpoint values obtained for DAMT-containing polymers. In particular, the DAMT-containing polymers perform very well at high inhibitor levels, where the effectiveness of the other inhibitors falls off.
TABLE m ~ILrc . I~t~l- Isr C~ F~ 2 (ppm) ~It lnh" ~ Levels of:
Compound Ratiol W~ht 5 ppm 20ppm 50 ppm 100 ppm poly(AA)3 100 % AA 5,300 383 ~ ' 39~ 350 287 poly(AA)3 100% AA 8,900 39~ 3~ ~12 154 p(AA/DAMT)4 70:30 4,400 372 417 473 593 p(AA/DAMT)4 80:20 8,400 383 439 550 615 p(AA/DAMT)4 90:10 9,900 383 417 462 593 diallvlmethyl -- -- -- 154 -- 189 taurine monomer I = The AA/diallyl methyltaurine monomer ratios are given in mole percent.
1 5 ~ = Calcium endpoints are listed in ppm ~s CaCO3 - --- 3 = poly(acrylic acid) 4 = poly(acrylic acid/diallyl methyltaurine) 5 = ~-phosphonobutane 1, 2, 4-tricarboxylic acid E~ample S
~0 In a typical calcium phosphate dispersancy experiment, a solution containing calcium (250 ppm as CaCO3), magnesium (125 ppm as CaCO3), orthophosphate (10 ppm as PO.~3~) and inhibitor ( I 0 ppm as the acid) was maintained at 70~C for four hours.
During this time, the pH of the stirred solution was kept at 8.50 by automated pH
monitoring and addition of 0.1 N NaOH. A blank solution, cont~inin~ no inhibitor ~5 treatment. was tested along side the inhibitor containing solutions. The concentration of phosphate in unfiltered samples (4.0 ml) taken from the test solution at the beginning of the experiment prior to calcium phosphate preci~ ion was compared with the concentration of phosphate in filtered samples (20.0 ml through a 0.45 rnicron filter) collected at the end of the expeTiment Percent phosphate dispersancy was calculated as:
% Disp. = [filtered final s~n~le] - [filtered blank] x 100 [unfiltered final sarnple] - [filtered blank]
with values approaching 100% indicating good calcium phosphate dispersancy.
The experimental procedure described above was used to obtain the results in Table IV. The best inhibition of calcium phosphate scale was observed for the low molecular weight copolymers of acrylic acid and DAMT. In addition, high performance 10 correlated with higher levels of DAMT in the copolymer. A copolymer of acrylic acid and DADMAC which also contained 10 mole percent sulfonate groups was tested as a control. This material did not perform well, showing the importance of the sulfobetaine structure present in polymers made from diallyl, methyltaurine.
TABLE IV
I j Calcium Phosphate Inhibition Tests Polymer Molecular Weight Monomer RatioPercent Inhibition Poly(AA/DAMT) 5,900 70/30 97%
Poly(AA/DAMT) 21,900 70/30 93%
Polv(AA/DAMT) 30~000 70/30 82%
Polv(AA/DAMT) 6~600 90/10 46%
Polv(AA/DAMT) 17.000 90/10 17%
Poly(AA/DADMAC), 5.600 70/30 2%
1 0~~O sulfomethylated none o%
F.Yample 6 '0 ln a typical calcium tolerance experiment. 200 ml of the desired calcium solution (500 to 1000 ppm) were placed in a '50 ml beaker and the pH was adjusted to 11 with 0.1 N NaOH. The calcium solution was placed in a jacketed flask cont~ining sufficient water to equal the level of solution in the beaker. Heated water from a 52~ water bath was then passed through the jacketed flask. Once a stable calcium solution telllp~ e was achieved, 600 ppm inhibitor solution (pH adjusted to 11) was added dropwise using a buret. The solution was monitored visually to determine the first signs of turbidity. Once 5 evidence of turbidity within the calciurn solution was noted, the titration was halted and the amount of inhibitor solution added to the calcium solution was recorded. The concentration of calcium in the test solution at the onset of turbidity was calculated taking into account the volume of the added inhibitor solution. Using the total solution volume in the beaker at the onset of turbidity, the concentration of inhibitor present in the test 10 solution at the onset of turbidity was calculated.
The ability of a potential calcium carbonate scale inhibitor to control deposit formation is dependent on the inhibitors availability during scale formation. Inhibitor chemistries which are stable towards precipitation at high calcium ion concentrations in the calcium tolerance test have a wider application range than less calciurn tolerant I 5 treatments. As shown in Table V, the polymers of the instant invention display superior performance in calcium tolerance testing.
TABLE V
- Calcium Tolerance InhibitorCalcium Concentration (ppm) Inhibitor Concentration at Onset of Turbidity4 (ppm) - PBTC' 480 19 p(AA) 480 18 p(AA/DAMT)~ 450 57 I = ~-phosphonobutane 1, 2, 4-tricarboxylic acid 5 ' = poly(acrylic acid) 5,000 MW
~ = 90'10 mole ratio of acrylic acid to diallyl methyltaurine 9,900 MW
4 = hi~her numbers for inhibitor concentration indicate better calcium tolerance Changes can be made in the composition, operation and arrangement of the method of the present invention described herein without departing from the concept and ~coF~e of the invention as defined in the following claims:
H2C~ ~CH2 CH fH
CH~) 5H2 /N\
R Rl--SO3 wherein R is selected from the group consisting of aLkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The invention is also a method of inhibiting the precipitation and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed I ~ t'rom the polymerization of a betaine of the formula:
H~C ~ .~CH2 CH fH
~ 5 / \
R Rl--SO3 wherein R is selected from the group con~i~tinE of alkyl and aryl groups, and R
is selected fr~n the group con~ nE of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A plefell~d polymer is a water-soluble copolymer of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
k.g.round of the Invention The utilization of water which contains certain inorganic h~ ilies, and the production and processing of crude oil water mixtures co..~ .E such hl~ ;lies, is 10 plagued by the precipitation of these impurities with subsequent scale formation. In the case of water which contains these cont~min~nt.c the harmful effects of scale formation are generally confined to the reduction of the capacity or bore of receptacles and conduits emploved to store and convey the cont~min~te~ water. In the case of conduits, the impedance of flow is an obvious consequence. However, a number of equally I ~ consequential problems are realized in specific utilizations of cont~min~ted water. For e~;ample scale formed upon the surfaces of storage vessels and conveying lines for process water may break loose and these large masses of deposit are entrained in and con~ eyed by the process water to damage and clog equipment through which the water is passed. e.~.~ tubes. valves. filters and screens. In addition, these crystalline deposits may '() appear in. and detract from. the final product which is derived from the process, e.g., paper formed from an aqueous suspension of pulp. Furthermore, when the cont~min:~t~cl water is involved in a heat exchange process, as either the "hot" or "cold" medium, scale will be formed upon the heat exchange surfaces which are contacted by the water. Such scale formation forms an insulating or thermal opacifying barrier which impairs heat transfer efficiency as well as impeding flow through the system.
Scale can also be formed during ~v~o.dLi~e cooling, when the level of dissolved ionic species will increase as water from the solution evaporates. Scale will then form 5 when the concentration of a salt exceeds its solubility under the conditions experienced.
This scaling process is typically observed in evaporative cooling towers, and the buildup of scale on the tower fill can cause a large decrease in tower efficiency.
While calcium sulfate and calcium carbonate are primary contributors to scale formation, other salts of ~lk~line-earth metals and the all..l,;llll... silicates are also 10 offenders. e.g., magnesium carbonate, barium sulfate, the alllminum silicates provided by silts of the bentonitic, illitic, and kaolinitic types among others. When phosphate anions are present. either naturally or added to the system, calcium phosphate scaling can also be significant.
Many other industrial waters, while not being scale forrning, tend to be corrosive.
1~ Such waters. when in contact with a variety of metal surfaces such as ferrous metals, aluminum. copper and its alloys. tend to corrode one or more of such metals or alloys. A
v ariety of compounds have been suggested to alleviate these problems. Such materials are low molecular weight polyacrylic acid polymers. Corrosive waters of this type are usually acidic in pH and are commonly found in closed recirculating systems.
'0 Numerous compounds have been added to these industrial waters in an attempt to prevent or reduce scale and corrosion. One such class of materials are the well known organophosphonates which are illustrated by the compounds hydroxyethylidene diphosphonic acid (HEDP) and phosphonobutane tricarboxylic acid (PBTC). Another group of active scale and corrosion inhibitors are the monoso(~ m ~h~sphinicobis (succinic acids~ which are described in U. S. Pat. No. 4,088,678. Fur~er, N, N-bis(phosphono methyl) derivative compounds in combination with homo or copolymers - are disclosed for inhibition of calcium c~bu.~ deposition in U. S. Patent No.
5 5,087,376.
Most industrial waters contain ~Ik~line earth metal cations, such as calcium, barium, magnesium, etc. and several anions such as bicarbonate, c~arbonate, sulfate, oxalate, phosphate, silicate, fluoride, etc. When combinations of these anions and cations are present in concentrations which exceed the solubility of their reaction products, 10 precipitates form until these product solubility concentrations are no longer exceeded.
For example, when the concentrations of calcium ion and carbonate ion exceed the solubility of the calcium carbonate reaction products, a solid phase of calcium carbonate u ill fonn. Calcium carbonate is the most common form of scale in many industrial processes .
1~ Solubility product concentrations are exceeded for various reasons, such as partial ev aporation of the water phase, chan~e in pH, pressure or temperature, and the introduction of additional ions which forrn insoluble compounds with the ions already present in the solution.
As these reaction products precipitate on surfaces of the water carrying system, ~() the! form scale or deposits. This accumulation prevents effective heat transfer, interferes w ith fluid flow, facilitates corrosive processes and harbors bacteria. This scale is an e~;pensive problem in many industrial water systems causing delays and shutdowns for cleaning and removal.
Scale deposits are generated and ~-~tenAffl-principaliyt~y -means of crystal growth;
and various a~ploaches to reducin~scale clevelopment have accordingly included inhibltion of crystal growth, modification of crystal growth and dispersion of the scale-forming rninerals.
Various polymeric treatments for scale controi exist Among them are the use of anionic co- or ter- polymers of N-vinyl-2-pyrrolidone or vinyl amide, as disclosed in U.S.
Patent No. 4,913,824; the use of maleic anhydride/4~ r ammonium-type polymers as disclosed in U.S. Patent No. 5,015,390 and the use of co- and ter-polymers of(meth)acrylic acid and sulfoalkyl(meth) acrylamide as disclosed in U.S. Patent No.
4~801,388.
Co-polymerization of N-(4-sulfoalkyl)N-methyldiallyl ammoniurn betaines with N-vinyl pyrrolidone or acrylamide to obtain a water-soluble co-polymer has been disclosed in U. S. Patent No. 4,585,846.
However, there is still a need for a polymeric treatment to more efficiently combat I 5 scale. The polymers described herein accomplish this purpose.
Summary of the Invention The invention is a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) amrnonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of an N.N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine ofthe formula:
H2C~ - ,~CH2 i .
CH ICH
CH~)/ H2 / \
R Rl--SO3 wherein R is selected from the group con.ci~ting of aLkyl and aryl groups, and Ris selected from the group comi~ting of alkyl groups, aryl groups, and alkylarylgroups, and an anionic monomer.
The invention is also a method of inhibiting the plecipi~lion and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-10 (sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polvmerization of a betaine of the formula:
H~C~ ~CH2 CH fH
CH~ (3 5H2 / \
R Rl--SO3 ~herein R is selected from the group consisting of alkyl and aryl groups, and R~is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
A pl~;rell~d polyrner is a water-soluble copoly ner of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine and acrylic acid.
Descr~ption of the Invention The invention is a water-soluble N,N-diallyl-N-allcyl-N-(sulfoalkyl) ammonium 5 betaine cont~ining copolymer, wherein said copolymer is formed from the polymerization of an N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine of the formula:
H2C~ ~CH2 CH fH
~ 5 /N\
R Rl--SO3 wherein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer.
The copolymer may have R selected from the group consisting of alkyl groups ha~ing about I to 20 carbon atoms and R~ selected from the group consisting of C~-C6 ~ ~ all~yl groups, phenyl groups. naphthyl groups~ benzyl groups, and naphthylmethyl groups.
The copolymer may be formed from an anionic monomer which is selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, ~ inyl sulfonic acid, styrene sulfonate. sodium acrylamido methyl propane sulfonic acid, and maleic acid.
Preferably, the water-soluble copolyrner is of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
The molecular weight of the copolymer may be from about 3,000 to about 100,000. Preferably, the molecular weight is from about 4,000 to about 50,000. Most preferably, the molecular weight is from about 4,000 to about 20,000.
The copolymer may have a molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid of from 0.5 :99.5 to 30:70. Preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl).ammonium betaine to acrylic acid is from 1:99 to 20:80. Most preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine to acrylic acid is from 3:97 to 10:90.
The invention is also a method of inhibiting the precipitation and deposition ofscale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed I ~ from the polymerization of a betaine of the formula:
H,C~ ~CH2 CH fH
CH, (3 5H2 / \
R R~--SO3 ~herein R is selected from the group consisting of alkyl and aryl groups, and R
is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups~
and an anionic monomer.
The anionic monomer may be selected ~rom the~ up consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, vinyl sulfonic acid, styrene sulfonate, sodium acrylamido methyl propane sulfonic acid, and maleic acid. R may be selected 5 from the group consisting of alkyl groups having about 1 to 20 carbon atoms and Rl may be selected from the group con~isting of Cl -C~ alkyl groups, phenyl groups, naphthyl groups, benzyl groups, and naphthylmethyl groups.
Preferably, the water-soluble copolymer is composed of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
10The molecular weight of the copolymer may be from about 3,000 to about 100.000. Preferably, the molecular weight of the copolymer may be from about 4,000 to about 50,000. Most preferably, the molecular weight of the copolymer may be from about 4.000 to about 20~000.
The molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to 15acrylic acid may be from 0.5:99.5 to 30:70. Preferably, the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) arnmonium betaine to acrylic acid is from 1:99 to 20:80. Most preferably~ the molar ratio of N~N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 3:97 to 10:90.
The water-soluble copolymer may be added to the industrial cooling water in an '0 amount of about 0.1 ppm to about 300 ppm. Preferably, the water-soluble copolymer may be added to the industrial cooling water in an amount of about 1 ppm to about 100 ppm. Most preferably. the water-soluble copolymer may be added to the industrial cooling water in an amount of about 5 ppm to about 50 ppm.
In the practice of this invention, a water-soluble anionic polymer and a phosphorous-co~ g scale inhibitor may also be added to the cooling water. The anionic polymer may be a sulfon~ted polyacrylate and the phosphorous-co."~ il-g scale inhibitor may be selected from the group conci~tin~ of 1-hydroxy ethylidene -1, 1-5 diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ammonium monophosphate, and aminotris(methylene phosphonic acid). Preferably, about 1 to about 300 ppm of the water-soluble copolymer of N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine and acrylic acid, from about 1 to about 50 ppm of the water-soluble anionic polymer and from about 1 to about 50 ppm of the phosphorous-cont~ining scale 10 inhibitor may be added to the cooling water.
The term scale as used herein refers to calcium carb~nate or calcium phosphate scale.
In addition to acrylic acid, other co-monomers can be polymerized with N,N-diallvl-N-alkyl-N~(sulfoalkyl) ammonium betaine such as methacrylic acid, maleic acid, 1~ maleic anhydride, itaconic acid, vinyl sulfonic acid, styrene sulfonate, sodium acrylamidomethylpropane sulfonic acid (AMPS) or nonionic monomers such as acrylamide. N-substituted acrylamides, vinyl acetate, or acrylate esters. As used herein, lhe term co-polymers is meant to encompass polymers formed from two or more different monomers .
~() The polymer can be applied to the system at any convenient point. For example, the proper amount of the polymer solution can be added either periodically or continuously to the make-up water.
The copolymers Qf this invention can be used in conj~l,~ion with other cooling - tower treating agents such as other scale inhibitors, corrosion inhibitors, and biocides.
As used herein, ~e term aL~cyl groups ~nco~ Acses those groups cont~ining oxygen fianctionalities such as ether, polyethers and alcohols.
The following examples are presented to describe pr~;r~ ;d embo.liment.c and utilities of the invention and are not meant to limit the invention unless otherwise stated in the claims appended hereto.
Example 1 - - -The following formulation was used for synthesis of the diallyl, methyltaurine monomer from N-methyltaurine, or sodium salt (formula: Me-NH-CH2CH2SO3Na) and allyl chloride. The systematic name for this monomer is: N,N-diallyl-N-methyl-N-(2-sulfoethyl)ammoniu n betaine. : ;
Diallyl Taurine F~rmulation .Fv. ~
Çhçnical W~t %MoleRatio N-Me~yl~unne 60.4 % 1.0 NaSalt (35% ac~ves) AllylChlonde 30.2 % 3.0 NaOH(50 %) 9.4 % 0.9 100.0%
The 35 % aqueous solution of N-methyltaurine sodiurn salt at pH 12 (138 g) was placed in a glass liner inside a stainless steel ~le~ reactor, and the first aliquot of ally chloride (35.8 g, 1.5 eq) was added. The reactor was sealed, stirring begun, and the mixture was heated to 80 - 85~ C at a pressure of 40 - 80 psi. After stirring for 0.5 hr, NaOH was injected to raise the pH to 11. Additional allyl chloride was added at 1 hour, 20 and more NaOH was introduced at 1.5 hr to increase the pH to 11. A final addition of N~OH was done at 2.0 hr., and the reaction was ended after 2.5 hr.
The reactor was cooled to give 220 g of crude product with pH near 6. Dl water (200 g) was added to the crude product~ and the solution was concentrated to give appro~imately 120 g of residue consisting of the desired monomer, NaCl, and some ~5 water. Dl water (~45 g) was added to give 165 g of solution cont~ining 40 wt % diallyl methyltaurine, plus NaCI. The solution was cooled, and precipitated NaCl was filtered of'f. The product was >90 % the desired diallyl methyltaurine, according to 13C NMR.
The remaining material was mono-allyl methyltaurine.
Low molecular-weight polymers of acrylic acid (AA) and diallyl, m~lhyl~u~ e (DAMT) were prepared by solution polymerization using redox initiators such as sodium bisulfite and ammonium persulfate. A semi-batch polym~n7~tion method was used whereby monomer and initiator solutions were fed into a reactor over the course of 1 5 hour.
Example 2 In a typical stress solubility experiment, 200 ml of a test solution col-t~ h-g 800 ppm CaCI2 and 800 ppm NaHCO3 (each as CaCO3) and the desired amount of inhibitor was placed in a 250 ml Erlenrneyer flask. A sample of the test solution was collected 10 prior to heating and sent for atomic absorption analysis in order to obtain a very accurate initial calcium concentration value.
The sample was then placed in the water bath and the solution is allowed to reach the water bath temperature. The pH electrode and NaOH line of an auto-titrator were then placed in the solution and the sample titrated to pH 9.00. Typically, the auto-] ~ titration system was set to the delayed stop mode so that the desired pH is approachedslowl~ and is not overshot. The time at which the sample reaches pH 9.00 was noted, the pH electrode and NaOH line rinsed. and the next sample was titrated to pH 9.00. The pH
- of the titrated solutions was checked and occasionally adjusted to pH 9.0 during the experiment.
'0 Two hours after a sarnple was first titrated to pH 9.00, the solution is removed from the water bath, 5 ml of the solution was removed using a syringe and filtered into a weighing boat. A portion of this sample, either 1.0, 2.0 or 3.0 ml, was then placed in a B.U.N. tube for Atomic Absorption (AA) analysis. The amount of solution was selected to give less than 60 ppm calcium (as calcium ion) when diluted to 25 ml. The samples were then analyzed by AA. - -The results from the diluted AA analysis sample, normally reported as ppmcalcium, were then used to calculate the concentration of soluble calciurn in the heated S test solution.
This experimental procedure was utilized to obtain the results detailed in Table I.
Lower ppm values for calcium precipitate indicate better scale inhibition. Table I results show that at above a 150 ppm treat rate, the polymers of the instant invention show performance as a calcium carbonate scale inhibitor which is superior to that of 10 poly(acrylic acid).
TABLE I
- Acrylate Pobmer Results - InhibitorInhibitor Concentration ~ Calcium ~r~c;l.ilate (ppm as actives) (ppm as CaCO3 ) p(AA)' 5 620 lO0 470 200 ~470 250 ~ 400 p(AA/DAMT)i 5 690 5 I = poly(acrvlic acid), 5,000 MW
' = 5 ppm 1-phosphono butane 1.~ 4 tricarboxylic acid added to each test solution = 90 10 mole ratio of poly (acrvlic acid diallyl methvltaurine) 6,000 MW
FY~ ple 3 The experimental procedure ~escribed in Example 2 was utili~d to obtain the results detailed in Table II.
- TABLE II
Sulfonated Polymers Results Inhibitor Concentration Calcium Precipitate Inhibitor (ppm as actives) (ppm as CaC03) p(AA/AMPS)I 5 800 p(AA/DADMAC) 5 795 p(AA/DAMT)3 5 790 I = 90/10 mole ratio of acrylic acid to sodium AMPS 6,000 MW
= 90/10 mole ratio of acrvlic acid to diallyl dimethyl ammonium chloride 4,900 MW
3 = 90/10 mole ratio of poly (acrylic acid/diallyl methyltaurine) 6,000 MW
l ( I Since lower values for the arnount of calcium precipitate were obtained for p( .~A!DAMT) than for the other polymers tested, the superiority of polymers of the instant invention is demonstrated. In addition, these results show that the sulfobetaine structure (RlN -CH,-CH~-SO3-) in the DAMT polymers is needed for best performance.
The polymers c~ either a sulfonate or a cationic monomer (DADMAC) did not - perforrn as well.~
. _ _ ~. _ .
F,Yample 4 S A hardness soluti~n of calciurn and m~ in a2:11Ca:Mg ratio and an ~lk~line solution of sodium carbonate/sodium bicarbonate buffered at pH 10 were simultaneously added to 200 rnL of an inhibitor test solution. The pH of the inhibitor test solution was adjusted-to bet~ZveeI}-7.~ ~ ium ~ cçip*~tion was detected by turbidity using a Brinkman PC-800 Colorimeter (420 nm wavelength). The hardness solution was prepared by adding 3.80 g calciurn acetate and 2.57 g m~gnesium acetate tetrahydrate to distilled water (100 rnL; total volurne~ The ~ snh~tion was prepared bv adding 2.01 g sodium bicarbonate and 1.27 g sodium carbonate to distilled water (100 mL total volume). A Masterflex pump delivered the hardness and aLkaline solutions at '.0 mL/min to the magnetically stirred-test solution.~ ~11 solutions~were aqueous and maintained at a constant temperature of 45~C. The titraeion endpoint, expressed as the ma~imum calciurn concentration (as calcium carbonate) before the onset of turbidity, was calculated from the elapsed time to a turbidity inflection on a strip chart recorder.
The procedure above was utilized to obtain the results ~f Table III. The p( AA/DAMT) showed superior performance to PBTC or p(AA), as illustrated by the '() lar~er endpoint values obtained for DAMT-containing polymers. In particular, the DAMT-containing polymers perform very well at high inhibitor levels, where the effectiveness of the other inhibitors falls off.
TABLE m ~ILrc . I~t~l- Isr C~ F~ 2 (ppm) ~It lnh" ~ Levels of:
Compound Ratiol W~ht 5 ppm 20ppm 50 ppm 100 ppm poly(AA)3 100 % AA 5,300 383 ~ ' 39~ 350 287 poly(AA)3 100% AA 8,900 39~ 3~ ~12 154 p(AA/DAMT)4 70:30 4,400 372 417 473 593 p(AA/DAMT)4 80:20 8,400 383 439 550 615 p(AA/DAMT)4 90:10 9,900 383 417 462 593 diallvlmethyl -- -- -- 154 -- 189 taurine monomer I = The AA/diallyl methyltaurine monomer ratios are given in mole percent.
1 5 ~ = Calcium endpoints are listed in ppm ~s CaCO3 - --- 3 = poly(acrylic acid) 4 = poly(acrylic acid/diallyl methyltaurine) 5 = ~-phosphonobutane 1, 2, 4-tricarboxylic acid E~ample S
~0 In a typical calcium phosphate dispersancy experiment, a solution containing calcium (250 ppm as CaCO3), magnesium (125 ppm as CaCO3), orthophosphate (10 ppm as PO.~3~) and inhibitor ( I 0 ppm as the acid) was maintained at 70~C for four hours.
During this time, the pH of the stirred solution was kept at 8.50 by automated pH
monitoring and addition of 0.1 N NaOH. A blank solution, cont~inin~ no inhibitor ~5 treatment. was tested along side the inhibitor containing solutions. The concentration of phosphate in unfiltered samples (4.0 ml) taken from the test solution at the beginning of the experiment prior to calcium phosphate preci~ ion was compared with the concentration of phosphate in filtered samples (20.0 ml through a 0.45 rnicron filter) collected at the end of the expeTiment Percent phosphate dispersancy was calculated as:
% Disp. = [filtered final s~n~le] - [filtered blank] x 100 [unfiltered final sarnple] - [filtered blank]
with values approaching 100% indicating good calcium phosphate dispersancy.
The experimental procedure described above was used to obtain the results in Table IV. The best inhibition of calcium phosphate scale was observed for the low molecular weight copolymers of acrylic acid and DAMT. In addition, high performance 10 correlated with higher levels of DAMT in the copolymer. A copolymer of acrylic acid and DADMAC which also contained 10 mole percent sulfonate groups was tested as a control. This material did not perform well, showing the importance of the sulfobetaine structure present in polymers made from diallyl, methyltaurine.
TABLE IV
I j Calcium Phosphate Inhibition Tests Polymer Molecular Weight Monomer RatioPercent Inhibition Poly(AA/DAMT) 5,900 70/30 97%
Poly(AA/DAMT) 21,900 70/30 93%
Polv(AA/DAMT) 30~000 70/30 82%
Polv(AA/DAMT) 6~600 90/10 46%
Polv(AA/DAMT) 17.000 90/10 17%
Poly(AA/DADMAC), 5.600 70/30 2%
1 0~~O sulfomethylated none o%
F.Yample 6 '0 ln a typical calcium tolerance experiment. 200 ml of the desired calcium solution (500 to 1000 ppm) were placed in a '50 ml beaker and the pH was adjusted to 11 with 0.1 N NaOH. The calcium solution was placed in a jacketed flask cont~ining sufficient water to equal the level of solution in the beaker. Heated water from a 52~ water bath was then passed through the jacketed flask. Once a stable calcium solution telllp~ e was achieved, 600 ppm inhibitor solution (pH adjusted to 11) was added dropwise using a buret. The solution was monitored visually to determine the first signs of turbidity. Once 5 evidence of turbidity within the calciurn solution was noted, the titration was halted and the amount of inhibitor solution added to the calcium solution was recorded. The concentration of calcium in the test solution at the onset of turbidity was calculated taking into account the volume of the added inhibitor solution. Using the total solution volume in the beaker at the onset of turbidity, the concentration of inhibitor present in the test 10 solution at the onset of turbidity was calculated.
The ability of a potential calcium carbonate scale inhibitor to control deposit formation is dependent on the inhibitors availability during scale formation. Inhibitor chemistries which are stable towards precipitation at high calcium ion concentrations in the calcium tolerance test have a wider application range than less calciurn tolerant I 5 treatments. As shown in Table V, the polymers of the instant invention display superior performance in calcium tolerance testing.
TABLE V
- Calcium Tolerance InhibitorCalcium Concentration (ppm) Inhibitor Concentration at Onset of Turbidity4 (ppm) - PBTC' 480 19 p(AA) 480 18 p(AA/DAMT)~ 450 57 I = ~-phosphonobutane 1, 2, 4-tricarboxylic acid 5 ' = poly(acrylic acid) 5,000 MW
~ = 90'10 mole ratio of acrylic acid to diallyl methyltaurine 9,900 MW
4 = hi~her numbers for inhibitor concentration indicate better calcium tolerance Changes can be made in the composition, operation and arrangement of the method of the present invention described herein without departing from the concept and ~coF~e of the invention as defined in the following claims:
Claims (26)
- Claims A water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of an N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine of the formula:
wherein R is selected from the group consisting of alkyl and aryl groups, and R1 is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer. - 2. The copolymer of Claim 1 wherein R is selected from the group consisting of alkyl groups having about 1 to 20 carbon atoms and R1 is selected from the group consisting of C1-C6 alkyl groups, phenyl groups, naphthyl groups, benzyl groups, and naphthylmethyl groups.
- 3. The copolymer of Claim 1 wherein said anionic monomer is selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, vinyl sulfonic acid. styrene sulfonate, sodium acrylamido methyl propane sulfonic acid, and maleic acid.
- 4. A water-soluble copolymer of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
- 5. The copolymer of claim 4 wherein the molecular weight is from about 3,000 to about 100,000.
- 6. The copolymer of claim 4 wherein the molecular weight is from about 4,000 to about 50,000.
- 7. The copolymer of claim 4 wherein the molecular weight is from about 4,000 to about 20,000.
- 8. The copolymer of claim 4 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 0.5:99.5 to 30:70.
- 9. The copolymer of claim 4 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 1:99 to 20:80.
- 10. The copolymer of claim 4 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 3:97 to 10:90.
- 11. A method of inhibiting the precipitation and deposition of scale on metal surfaces in contact with industrial cooling waters comprising the addition of an effective, scale-inhibiting amount of a water-soluble N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine containing copolymer, wherein said copolymer is formed from the polymerization of a betaine of the formula:
wherein R is selected from the group consisting of alkyl and aryl groups, and R1 is selected from the group consisting of alkyl groups, aryl groups, and alkylaryl groups, and an anionic monomer. - 12. The method of claim 11 wherein said anionic monomer is selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, vinyl sulfonic acid, styrene sulfonate, sodium acrylamido methyl propane sulfonic acid, and maleic acid.
- 13. The copolymer of Claim 11 wherein R is selected from the group consisting of alkyl groups having about 1 to 20 carbon atoms and R1 is selected from the group consisting of C1 -C6 alkyl groups, phenyl groups, naphthyl groups, benzyl groups, and naphthylmethyl groups.
- 14. The method of Claim 11 wherein the water-soluble copolymer is composed of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine and acrylic acid.
- 15 . The method of Claim 14 wherein the molecular weight of the copolymer is from about 3,000 to about 100,000.
- 16. The method of Claim 14 wherein the molecular weight of the copolymer is from about 4,000 to about 50,000.
- 17. The method of Claim 14 wherein the molecular weight of the copolymer is from about 4.000 to about 20,000.
- 18. The copolymer of Claim 14 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 0.5:99.5 to 30:70.
- 19. The copolymer of Claim 14 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 1:99 to 20:80.
- 20. The copolymer of Claim 14 wherein the molar ratio of N,N-diallyl-N-methyl-N-(2-sulfoethyl) ammonium betaine to acrylic acid is from 3:97 to 10:90.
- 21. The method of Claim 14 wherein the water-soluble copolymer is added to the industrial cooling water in an amount of about 0.1 ppm to about 300 ppm.
- 22. The method of Claim 14 wherein the water-soluble copolymer is added to the industrial cooling water in an amount of about 1 ppm to about 100 ppm.
- 23. The method of Claim 14 wherein the water-soluble copolymer is added to the industrial cooling water in an amount of about 5 ppm to about 50 ppm.
- 24. The method of Claim 14 further comprising the addition of a water-soluble anionic polymer and a phosphorous-containing scale inhibitor to the cooling water.
- 25. The method of Claim 24 wherein the anionic polymer is a sulfonated polyacrylate and the phosphorous-containing scale inhibitor is selected from the group consisting of 1-hydroxy ethylidene -1, 1-diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ammonium monophosphate, and aminotris(methylene phosphonic acid).
- 26. The method of Claim 25 wherein from about 1 to about 300 ppm of the water-soluble copolymer of N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine and acrylic acid, from about 1 to about 50 ppm of the water-soluble anionic polymer and from about 1 to about 50 ppm of the phosphorous-containing scale inhibitor are added to the cooling water.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/715,778 | 1996-09-19 | ||
| US08/715,778 US5788866A (en) | 1996-09-19 | 1996-09-19 | Copolymers formed from polymerization of N,N-diallyl-N-alkyl-N-(sulfoalkyl) ammonium betaine and their utility as calcium carbonate scale inhibitors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2202946A1 true CA2202946A1 (en) | 1998-03-19 |
Family
ID=24875443
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002202946A Abandoned CA2202946A1 (en) | 1996-09-19 | 1997-04-17 | Sulfobetaine-containing polymers and their utility as calcium carbonate scale inhibitors |
Country Status (6)
| Country | Link |
|---|---|
| US (2) | US5788866A (en) |
| EP (1) | EP0832854B1 (en) |
| JP (1) | JPH10101744A (en) |
| AU (1) | AU1913697A (en) |
| CA (1) | CA2202946A1 (en) |
| DE (1) | DE69709009T2 (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5902560A (en) * | 1997-08-28 | 1999-05-11 | Nalco Chemical Company | Method for inhibiting precipitation of sodium oxalate in a Bayer process liquor |
| US6313246B1 (en) | 1999-07-07 | 2001-11-06 | Nalco Chemical Company | High molecular weight zwitterionic polymers |
| US6436154B1 (en) * | 2000-09-28 | 2002-08-20 | Fmc Wyoming Corporation | Use of dodecylbenzene sulfonic acid or salt as a scale inhibitor |
| US6709551B2 (en) | 2001-12-17 | 2004-03-23 | Ondeo Nalco Company | High molecular weight cationic and anionic polymers comprising zwitterionic monomers |
| US20060183863A1 (en) * | 2005-02-14 | 2006-08-17 | Ciphergen Biosystems, Inc. | Zwitterionic polymers |
| GB0516068D0 (en) * | 2005-08-04 | 2005-09-14 | Champion Technologies Ltd | Well treatment |
| GB0600692D0 (en) * | 2006-01-13 | 2006-02-22 | Champion Technologies Ltd | Well treatment |
| GB0616469D0 (en) * | 2006-08-17 | 2006-09-27 | Champion Technologies Ltd | Well treatment |
| US10689280B2 (en) * | 2009-12-31 | 2020-06-23 | Ecolab Usa Inc. | Method for the removing and reducing scaling |
| CN102452961B (en) * | 2010-10-25 | 2013-11-06 | 中国石油化工股份有限公司 | Diallyl monomer and polymer thereof and preparation method thereof |
| US9481765B2 (en) | 2013-12-30 | 2016-11-01 | King Fahd University Of Petroleum And Minerals | Synthesis of a diallylammonium/SO2 copolymer bearing phospho- and sulfopropyl pendents |
| DE102014017962A1 (en) * | 2014-12-05 | 2016-06-09 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Detergents and cleaning agents with polymeric agent |
| SG11202001163UA (en) | 2017-08-30 | 2020-03-30 | Ecolab Usa Inc | Molecules having one hydrophobic group and two identical hydrophilic ionic groups and compositions thereof |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4088678A (en) * | 1976-07-01 | 1978-05-09 | Nalco Chemical Company | Substituted succinic acid compounds and their use as chelants |
| US4585846A (en) * | 1985-01-02 | 1986-04-29 | Exxon Research And Engineering Co. | Cyclopolymerizable sulfobetaine monomer |
| US4913824A (en) * | 1985-10-21 | 1990-04-03 | Nalco Chemical Company | Anionic polymers containing N-vinyl-pyrrolidone or other vinyl amides as scale inhibitors for preventing or reducing calcium phosphate and other scales |
| US4801388A (en) * | 1986-03-21 | 1989-01-31 | Nalco Chemical Company | Modified acrylamide polymers used as scale inhibitors |
| US5015390A (en) * | 1988-07-05 | 1991-05-14 | Calgon Corporation | Method for controlling scale deposition in aqueous systems using quaternary ammonium/maleic anhydride-type polymers |
| US5087376A (en) * | 1990-10-15 | 1992-02-11 | Calgon Corporation | Multifunctional scale inhibitors |
| DE4200132A1 (en) * | 1992-01-01 | 1993-07-08 | Ballschuh Detlef | New poly-1-sulpho:propyl-3,4-di:methylene-pyrrolidinium betaine(s) - useful as viscosifiers or sacrificial agents in enhanced oil recovery |
| US5415782A (en) * | 1993-11-22 | 1995-05-16 | Nalco Chemical Company | Method for the alteration of siliceous materials from bayer process liquors |
-
1996
- 1996-09-19 US US08/715,778 patent/US5788866A/en not_active Expired - Fee Related
-
1997
- 1997-04-17 CA CA002202946A patent/CA2202946A1/en not_active Abandoned
- 1997-04-28 AU AU19136/97A patent/AU1913697A/en not_active Abandoned
- 1997-05-14 JP JP9123655A patent/JPH10101744A/en active Pending
- 1997-09-02 EP EP97115195A patent/EP0832854B1/en not_active Expired - Lifetime
- 1997-09-02 DE DE69709009T patent/DE69709009T2/en not_active Expired - Fee Related
-
1998
- 1998-05-14 US US09/078,463 patent/US6225430B1/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP0832854A1 (en) | 1998-04-01 |
| AU1913697A (en) | 1998-03-26 |
| DE69709009T2 (en) | 2002-08-22 |
| US6225430B1 (en) | 2001-05-01 |
| DE69709009D1 (en) | 2002-01-24 |
| JPH10101744A (en) | 1998-04-21 |
| US5788866A (en) | 1998-08-04 |
| EP0832854B1 (en) | 2001-12-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4650591A (en) | Acrylic acid/2-acrylamido-2-methylpropylsulfonic acid/2-acrylamido-2-methylpropyl phosphonic acid polymers as scale and corrosion inhibitors | |
| EP0206814B1 (en) | Water-soluble polymers and their use in the stabilization of aqueous systems | |
| KR100904789B1 (en) | Method for controlling scale formation and deposition in aqueous systems | |
| US4566973A (en) | Scale inhibition in water systems | |
| US4374733A (en) | Method for treating aqueous mediums | |
| US5716529A (en) | Water-treating agent and method for treating water | |
| AU2016200974A1 (en) | Thermally stable scale inhibitor compositions | |
| AU621137B2 (en) | Method for controlling scale deposition in aqueous systems using allyl sulfonate maleic anhydride polymers | |
| US6017994A (en) | Utility of water-soluble polymers having pendant derivatized amide functionalities for scale control | |
| CA2202946A1 (en) | Sulfobetaine-containing polymers and their utility as calcium carbonate scale inhibitors | |
| JP2801465B2 (en) | How to prevent corrosion and scale on metal surfaces | |
| US6001264A (en) | Water-treating agent and method for treating water | |
| WO2009148978A1 (en) | Method for inhibiting the formation and deposition of silica scale in aqueous systems | |
| US20070055022A1 (en) | Polymer for water treatment | |
| US4446045A (en) | Composition for treating aqueous mediums | |
| JP4019331B2 (en) | Water treatment agent | |
| FI80282C (en) | Use of acrylic polymer to inhibit the formation of particulate matter or as a dispersant in water systems | |
| Amjad | Development of Calcium Phosphate Inhibitng Polymers for Cooling Water Applications | |
| US20070093609A1 (en) | Acrylic-acid-based homopolymers comprising taurine modified for the treatment of water | |
| Amjad | Inhibition of Calcium Phosphate Deposits in Industrial Waters | |
| EP0516357A1 (en) | Anionic/cationic polymer mixture for scale inhibition | |
| CA2544771A1 (en) | Taurine-modified acrylic acid-based homopolymers for water treatment | |
| MXPA98005251A (en) | Method to prevent the formation of incrustation in metal surfaces in contact with water industr | |
| CA2066081A1 (en) | Phosphonate-containing polymers used as scale and corrosion inhibitors |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |