US 3817953 A
In a process in which a C5 fraction from a cracked naphtha or gas oil is polymerised with the help of a Friedel-Crafts catalyst to produce a petroleum resin, the C5 fraction is first heated to a temperature of 160 DEG to 250 DEG C for a period of up to 5 hours and is then held at a temperature in the range 100 DEG to 160 DEG C for a further period of up to 5 hours.
Description (OCR text may contain errors)
United States Patent [191 Younger PETROLEUM RESINS  Inventor: Donald Anthony Younger,
Stockton-on-Tees, England  Assignee: Imperial Chemical Industries Limited, London, England  Filed: Dec. 1, 1972  Appl. No.: 311,152
 Foreign Application Priority Data Dec. 15, 1971 Great Britain 58225/71  US. Cl 260/82, 260/33.6 PQ
 Int. Cl. C08f 15/04, C08f 15/42  Field of Search 260/82 56] References Cited UNITED STATES PATENTS 2,750,359 6/1956 Hamner et a1. 260/82 June 18, 1974 2,775,576 12/1956 Hamner et al. 260/82 2,817,647 12/1957 Habeshaw et a1 260/82 3,709,854 l/1973 Hepworth et a1. 260/82 Primary Examiner-Harry Wong, Jr.
Attorney, Agent, or Firm -Cushman Dabry &
Cushman  ABSTRACT 10 Claims, 1 Drawing Figure PETROLEUM RESINS This invention relates to the production of petroleum resins.
ln our co-pending U.S. Patent application Ser. No. 177,113, now U.S. Pat. No. 3,709,854, we have described and claimed a process for the production of a hydrocarbon feedstock suitable for the production of a petroleum resin and also a process for the production of such a resin. 1n the production of the hydrocarbon feedstock a C stream distilled from a cracked naphtha or gas oil is preheated before conversion to the resin by heating it to a temperature of at-least 160C for a period of up to 5 hours. Preferably the C stream is heated to a temperature in the range 160 to 200C and the time of heating is suitably 0.05 to 1.5 hours. It is also disclosed in our copending application that the preheating of the C feedstock may be carried out in a continuous or batchwise manner. The present invention is particularly applicable to the continuous process and provides a means whereby the I concentration of monocyclopentadiene in the feed to thepolymerisation is kept as low as possible.
According to the present invention a C stream distilled from a cracked naphtha or gas oil is preheated'before conversion to the resin to a temperature of at least 160C fora period of up to 5 hours, and is then held at a temperature between 100 and 160C for a further period of up to 5 hours.
Preferably the C stream is preheated to a temperature in the range 160 to 250C, more preferably 160 to 200C.
Preferably the C stream is held at a temperature of between 100 and 160C for 0.05 to 1.5 hours and preferably the temperature is between 130 and 150C. The desired temperature may be achi'eved isothermally or adiabatic conditions may be applied in which case the temperature may vary over a given period of time within the range specified. At temperatures between 100 and 160C the monocyclopentadiene which is present at the temperatures .above 160C dimerises to dicyclopentadiene.
The C stream is derived from a thermally or steam cracked naphtha or gas oil and-typically boils in the range to 80C. It may contain the following hydrocarbons: isoprene, cis and trans piperylene, npentane,'isopentane, pentene-l, cyclopentadiene, dicyclopentadiene, trans-pentene-2, 2-methylbutene-2, cyclopentene, cyclopentane and benzene. In addition some C hydrocarbons may also be present. If desired this C stream may be further refined before being used in the process of the present invention, e.g. the isoprene may be removed by distillation and/or the monocyclopentadiene may be dimerised by heating at a temperature of 100 to 160C, e.g. at 120C, preferably for up to 5 hours, more preferably for 0.05 to 1.5 hours. Although the monocyclopentadiene content of the C stream may be reduced by this means the following temperature rise above 160C tends to convert some of the dimer back to the monomer. If the C stream is cooled directly from the temperature above 160C the C stream retains the increased concentration of the monocyclopentadiene and gives an inferior resin. By means of the present invention the concentration of monomer is once more reduced.
It is preferred to carry out the heat soaking stages continuously and this may conveniently be effected in 2 tubular reactors in which the feedstock passes through a tube, the residence time being that required for the specific heat soak to take place. Each tube may be maintained at the desired temperature, i.e. the conditions are isothermal or the system may be maintained under adiabatic conditions in which the heat generated by the reactions taking place may be used to obtain a temperature rise or to maintain a desired temperature. For example the first stage may be adiabatic with the temperature rising from to 180C, the second may be isothermal at 180C, and the third adiabatic at 100 to 160C, the heat of dimerisation maintaining the temperature within this range,'e.g. at to C. 1f necessary cooling means may be'provided between stages to achieve the desired temperatures; When the C stream has been subjected to the pretreatment in accordance with the present invention it may be polymerised by meansof a catalyst to produce a resin. Thus Friedel Crafts catalysts are suitable, e.g. inorganic halides and inorganic strong acids. Inorganic halides are generally preferred and include halides of aluminium, iron, tin, boron, zinc, antimony and titanium which may be used in conjunction with a hydrogen halide such as hydrogen chloride. For example,"
treatment with aluminium chloride preferably complexed with hydrogen chloride in an aromatic solvent such astoluene'or a xylene produces a solution from which the resin may be recovered. Preferably, however, the Friedel Crafts catalyst is used in an aromatic solvent which is a benzene which is liquid at the temperature of the polymerisation and which is substituted by at least one secondary or tertiary alkyl group or by a cycloalkyl group, e.g. tert butyl benzene, p-cymene, p-isobutyl toluene, p-ethyl-tert amyl benzene or, in particular, cumene. Such catalysts are described in our copending British Patent Application No. 5097/71; (equivalent Belgian Patent No. 779,454) a complex of aluminium chloride, cumene and hydrogen chloride being preferred. The polymerisation of the C feedstock is preferably carried out at a temperature of 100 to-+200C, more preferably 50 to 100C under atmospheric pressure or a positive pressure, e.g. up to 700 p.s.i.g., using a catalyst concentration of 0.05 to 5 percent, preferably 0.5 to 1.5 percent by weight of the C 'stream. The catalyst is'finally broken down and removed from the polymer by treatment, for example with alcoholic ammonia, aqueous alkali or aqueous alcohol followed by one or more washes with water and,
' optionally, a steam distillation to remove residual monomers. Suitable alcohols are alkanols containing one to four carbon atoms, e.g. isopropanol and suitable alkalis are the alkali metal hydroxides such as sodium hydroxide.
The polymerisation is preferably carried out continuously more preferably by passage through a plurality of alternating polymerisation and cooling zones in which catalyst is added to each polymerisation zone. As the polymerisation is exothermic the temperature rises adiabatically in each polymerisation zone only to drop in the next cooling zone preparatory to further polymerisation in the subsequent polymerization zone. For most practical purposes the cooling zones may be water cooled. The polymerisation and cooling zones may comprise any vessels in which the desired processes can take place but tubular reactors are particularly suitable. In this case the preheated C feedstock together with catalyst passes through a tube in which its residence time is predetermined and through which the temperature rises due to the heat of polymerisation. The next tube is cooled and the residence time of the hydrocarbon is such that the required drop in temperature takes place during the passage of the hydrocarbon along the tube. The following tubular reactor is a polymerisation zone and additional catalyst is introduced into the hydrocarbon feed. There may suitably be two to eight pairs of such polymerisation and cooling zones, particularly three to five pairs. The amount of catalyst added overall is shared between the various polymerisation zones so as to achieve approximately the same temperature rise and hence the same conversion in each zone. I
The removal of the catalyst and the final washing of the polymer may also be carried out continuously, e.g. in aseries of mixers and settlers. The polymer is finally stripped of residual C stream hydrocarbons, e.g. by a steam distillation, and is then ready for use.
The invention will now be further described with reference to the attached block diagram.
A C stream comprising isoprene, cisand transpiperylene, n-pentane, isopentane, pentene-l, cyclopentadiene, dicyclopentadiene, trans-pentene-2, 2- methylbutene-2, cyclopentene, cyclopentane and benzene is stored in storage tank 1 from which it is fed continuously to three tubular reactors 2, 3 and 4 in series. In the first reactor the temperature of the C stream is allowed to rise adiabatically from 120C to 180C as the exothermic dimerisation of the cyclopentadiene 20 for a repeat of the isopropanol/water washing process, the isopropanol/water being fed in through line 21 and the spent wash liquor being removed via line 22. A third wash with water alone takes place in mixer 23 and settler 24, the water being fed in through line 25 and removed from the mixer via line 26. The washed polymer solution is held in a storage tank 27 from which it is fed to a final steam distillation unit 28 from the base of which is recovered molten resin which is solidified in, for example, pastillated form while the distillate comprising water and unreacted hydrocarbons is sent for recovery.
EXAMPLE 1 p.s.i.g.
EXAMPLES 2 TO 7 The procedure followed in Example 1 was repeated in Examples 2 to 7 using C streams with different contents of monocyclopentadiene. The results were as follows:
EXAMPLE 2 3 4 S 6 7 8 Initial monocyclopcntadicnc ('71 wt.) 15.7 13.9 13.1 12.4 10.5 10.3 9.11 Temp. of first heat soak (C) 180 1110 180 180 180 170 160 Time of first heat soak (mins) 32 36 I2 18 411 48 Monocyclopentadiene content after first heat soak (71 wt.) 2.0 2.1 1.6 2.1 2.0 1.6 1.4 Temp. of second heat soak (C) 150 150 150 150 140 140 140 Time of second heat soak (mins.) 64 48 48 48 48 48 40 Final monocyclopentadiene. content (7: wt.) 1.0 0.3 1.0 1.0 0.9 1.0 0.9
7 EXAMPLE 8 takes place and is then held at this temperature in the second reactor. After leaving the second reactor the temperature of the stream is decreased to 135C and is then held at this temperature in the third reactor. The residence time of the C stream is each reactor is '5, 20 and 40 minutes respectively. After passing through the third reactor the hydrocarbon stream is cooled to 60C in water cooler 5 and is then fed continuously to a series of tubular polymerisation reactors 6, 7, 8 and .9 interposed with water coolers 10, ll, 12 and 13 respectively. Catalyst is fed from a storage tank 14 to each polymerisation reactor. The catalyst is a liquid complex of aluminium chloride, hydrogen chloride and cumene and is fed to the four polymerisation reactors in such amounts as to give the same temperature rise in each reactor. The temperature of the hydrocarbon stream rises in each reactor to 90 to 100C and is then reduced to 60C in each subsequent cooler. Residence time in each reactor is approximately 3 minutes. After leaving the last cooler 13 the polymerised product is mixed with 10 percent of its weight of a 1:1 mixture of water and isopropanol from line 15 in mixer 16 and then allowed to settle in settler 17. The isopropanol/- water/aluminium chloride is removed from the settler by line 18 for recovery of the isopropanol while the polymer solution is pumped to a mixer 19 and settler 2.5 Kilograms of a C stream was heated to a temperature of 180C in a 5-litre autoclave and washeld at this temperature for 25 minutes. The temperature in the autoclave was then allowed to fall to 150C and was held at this temperature for a further 40 minutes. This resulted in a polymerisation feedstock of the following compositioni 3-methylbutene-l (0.4% wt.), pentene-l (2.8% wt.), 2-methy1butene-1 (5.1% wt.). pentene-2 (1.7% wt.) isoprene 12.9% wt.), 2-methylbutene-2 (2.8% wt.). trans-piperylene (5.6% wt.), cis-piperylene (3.3% wt.). cyclopentene (3.1% wt.). dicyclopentadiene (13.3% wt. mixed dimers of isoprene, piperylem: and cyclopentadiene (5.7% wt.).
the temperature decreased to C. 10 m1. of catalyst was then added when the temperature rose again to 107C. The reaction mixture was again cooled to 60C and again 10 mls. of catalyst added. Following further cooling to 60C the final 20 mls. of catalyst were introduced and after 2 minutes reaction the mixture was cooled down to ambient temperature. In total 68 mls. of catalyst complex were added which contained a total of 19.8 grams of aluminium chloride.
The resin solution resulting from the polymerisation was stirred gently with a 1:1 mixture by volume of isopropanol and water (300 mls.) and allowed to settle. The resin layer was separated and the process repeated. Finally the resin solution was washed'with two separate amounts of water (300 mls. each). The resin was isolated by distillation, firstly at atmospheric pressure with a sidearm take-off and boiler temperature up to 180C to remove unpolymerised constituents of the C stream and lastly at 50 mm. pressure and boiler temperature 200C.
The yield of resin was 38% by weight based on the weight of C stream used and was found to have a Gardner colour of l 1 (50% solution in toluene), a softening point (ball and ring) of 108C and melt viscosity 4.1 poise at 200C and 78.4 poise at 130C.
1 claim: v
1. In a process for the production of a petroleum resin soluble in hydrocarbon solvents by polymerising in the presence of a Friedel-Crafts catalyst a C stream which has been distilled from a cracked naphtha or gas oil and which has been heated to a temperature in the range of 160 to 250C for a'period of up to five hours before carrying out the polymerisation the improvement whereby after heating to in the range of 160C to 250C but before the polymerisation, the C stream is cooled to and held at a temperature between 100 and 160C for a further period of 0.05 up to 5 hours.
2. The process of claim 1 in whichv the C stream is held at a temperature of between 100 and 160C for a period of 0.05 to 1.5 hours.
3. The process of claim 1 in'which the C stream is held at a temperature of between 130 and 150C.
4. The process of claim 1 in which monocyclopentadiene is first dimerised by heating the C stream at a temperature of 100 to 160C for up to 5 hours.
5. The process of claim 1 in which the heating stages are carriedout in tubular reactors.
6. The process of claim 1 in which cooling means are 7 provided between the heating stages.
nally broken down and removed from the polymer by treatment with alcoholic ammonia, aqueous alkali or aqueous alcohol.
10. The process of claim 1 in which a C stream boiling in the range 10 to 80C is,
a. heated to a temperature in the range 100 to 160C for 0.05 to 1.5 hours to dimerise monocyclopentadiene,
b. is then heated at 160 to 220C for a period of 0.05 i
to 1.5 hours, c. is next held at 130 to 150C for 0.05 to 1.5 hours,
d. is contacted with a catalyst comprising aluminium cumene,
e. is treated with aqueous sodium hydroxide or aqueous isopropanol, and
f. is. water washed and separated from residual C hydrocarbons by distillation to yield a petroleum resin.
chloride, hydrogen chloride and toluene, xylene or