GB2089832A - Oligomerized higher olefins - Google Patents

Abstract

A selective catalyst for the oligomerization of olefins having at least 10 carbon atoms is provided by perfluorosulfonic acid resin. The oligomerized product is useful as a lubricant, preferably after hydrogenation. Suitable olefins for oligomerization include C10-C20 alpha -olefins, C10- C28 internal olefins, C10-C32 vinylidene olefins, C13C20 olefin mixtures obtained by dehydrogenation or pyrolysis of paraffins, and olefins obtained from the polymerization product of ethylene, optionally with disproportionation of ethylene polymers outside the desired molecular weight range for oligomerization.

Description

SPECIFICATION Oligomerized higher olefins This invention relates to the oligomerization of mono olefins, and to products, useful as lubricants obtained by such a process.

It is known that the oligomerization of olefins can be carried out using Friedel-Crafts catalysts. U. S. Patent No 4,218,330 discloses dimerizing C-12 to C-18 alpha olefins; U. S. Patent No 3,742,082 discloses dimerizing C-6 to C-10 alpha olefins; U. S. Patent No 3,149,178 discloses oligomerizing C-6 to C12 alpha olefins; and U. S. Patent No 3,576,898 discloses oligomerizing vinylidene olefins. The product obtained using Friedel Crafts catalysts, such as boron tri-fluoride or aluminium chloride, requires washing after oligomerization to remove catalyst and subsequent drying.

U. S. Patent No 4,065,512 discloses the use of per-fluorosulfonic acid resin membranes to catalyze the hydration and/or polymerization of isobutene. U. S. Patent No 4,038,213 shows that similar polymers can be used for the alkylation of isoparaffins by addition of an olefin, and other reactions. It discloses that olefins of from C-2 to C-S will polymerize if the isoparaffin is not used in large excess.

It has now been found that olefins of much higher molecular weights are oligomerized, mostly to lower oligomers, using solid perfluorosulfonic acid resins.

The present invention provides a process for oligomerizing an olefin having at least 10 carbon atoms by contacting the olefin with a catalyst, wherein the catalyst comprises a perfluorosulfonic acid resin.

According to one preferred embodiment, the oligomerized product is hydrogenated.

Suitable olefins which can be oligomerized in accordance with various embodiments of the invention include: (A) an a-olefin having 10 to 20 carbon atoms; (B) and internal mono olefin having 10 to 28 carbon atoms; (C) a vinylidene olefin having 10 to 32 carbon atoms; (d) a mixture having 1 3 to 20 carbon atoms obtained by was cracking of paraffins.

(E) a mixture obtained by dehydrogenating a mixture of linear paraffins having 1 3 to 20 carbon atoms; (F) mono olefins having an even number of carbon atoms in the range from 10 to 1 8 obtained by disproportionating linear a-olefins having up to 10 carbon atoms, isolated from a mixture resulting from the polymerization of ethylene; and (G) a-olefins having 10 to 20 carbon atoms isolated from a mixture obtained by polymerizing ethylene.

One embodiment of the invention comprises (i) polymerizing ethylene to a mixture of aolefins, (ii) isolating and oligomerizing a-olefins having 1 4 to 20 carbon atoms, from the product of step (i) (iii) isomerizing/disproportionating olefins from step (i) having less than 14 and more than 20 carbon atoms, and (iv) isolating and oligomerizing a-olefins having 1 4 to 20 carbon atoms from the product of step (iii).

Optionally, olefins from step (iv) having less than 14 and more than 20 carbon atoms, are (v) isomerized/disporportionated, and steps (iv) and (v) are repeated at least once.

Preferred perfluorosulfonic acid resins that can be used according to the invention are copolymers of sulfonyl fluorovinyl ether and a fluorocarbon, and may comprise repeating units of the formula:

in which n and zaire numbers. Actually the so called XR resin (the sulfonyl fluoride form) is produced first, and made into film. Then the fluoride film is hydrolyzed to the sodium solfonate form which is finally converted into the acid form.

The formula weight corresponding to one sulfonic acid group is called the equivalent weight. The properties of the resin depend on the equivalent weight; the higher the equivalent weight, the higher is the mechanical strength, but also the higher is the electrical resistance. Perfluorosulfonic acid resin with useful properties generally has an equivalent weight ranging from 1,100 to 1,500, corre spondingtoz = 1,and = 15 to 20.

The commercial resin is available as a membrane from 0.125 to 0.25 mm. thick and is sometimes laminated with a polytetrafluoroethylene web to improve mechanical strength and dimensional stability. The resin is also available in pellet and powder form. The physical form of the resin is a matter of choice for one skilled in the art. All forms will provide the catalytic effect of this invention. Engineering considerations will determine the most suitable physical form.

A further description of the perfluorosulfonic acid resin is given in duPont "Innovation", Volume 4, No.3, Spring 1973 and in U.S. Patent No. 4,038,213.

The olefins to be oligomerized in this invention should be predominantly mono olefins although the presence of dienes and other olefinic types can be tolerated. The oligomerization process will take place in the presence of alpha olefins, vinylidene olefins, and inter nal olefins alone or in various mixtures.

In one embodiment of the invention, the olefin feed comprises predominantly alpha olefin. The alpha olefin feed should range from C-10 to C-20, preferably from C-12 to C-16. In an especially preferred embodiment, the olefin feed is predominantly alpha and mainly tetradeceme (C-14).

In another embodiment of the invention, the olefin comprises predominantly internal mono olefin. The internal olefin feed should range from C-10 to C-28, preferably from C-12 to C-20. In an especially preferred embodiment, the internal olefin is mainly C-14.

In yet another embodiment of the invention the olefin comprises predominantly vinylidene olefin. The vinylidene olefin should range from C-10 to C-32, preferably from C-12 to C-20. In an especially preferred embodiment, the vinylidene olefin is mainly C-14.

Mixtures of alpha, internal and vinylidene olefins may be used as needed to control properties of the oligomerized product.

In another embodiment of the invention, the olefins that are oligomerized are in the form of a mixture having 1 3 to 20 carbon atoms obtained by the wax cracking (i.e. pyrolysis) of paraffins. Wax pyrolysis is a well known procedure, and is described for example in U.S. Patents No 2945076 and 2172228.

In yet another embodiment of the invention the olefins to be oligomerized are in the form of a mixture obtained when paraffins having 1 3 to 20 carbon atoms are dehydrogenated according to known technology, resulting in a mixture of paraffins and olefins. The process of dehydrogenation of paraffins used is described in various publications, for example, U.S. Patents No. 3,448,166; 3,448,165; 3,456,031; 3,429,944; 3,458,592; 3,458,543; 3,248,451; 3,274,287; 3,315,007 and 3,315,008.

This mixture of paraffins and olefins is then contacted according to the invention, with perfluorosulfonic acid resin in the acid form.

Monomers of olefin and unreacted paraffin are optionally recycled and the residue of oligomerized olefins is preferably partially or completely hydrogenated using conventional technology, as will be further discussed below.

In another embodiment of this invention, the olefins to be oligomerized are obtained by a two step process. In the first step, ethylene is transformed into linear alpha olefins using Ziegler technology as disclosed in various patents, including U.S. Patents No. 3,424,815; 3,482,000; 3,424,816; 3,444,264; 3,444,263; 3,502,741; 3,510,539; 3,478,124; and 3,441,631. The result of this conversion of ethylene is a mixture of alpha olefins. In the second step, C-6, C-8 and C-10 alpha olefins from the mixture are homodisproportionated into linear symmetrical mono olefins having even numbers of carbon atoms e.g. C-10, C-14, and C-18.This disproportionation reaction is described in various documents including the following: "Olefin Disproportionation", Catalysis Review 3, 37 (1969); Hydrocarbon Processing, Aug., 11 9 (1976); Quarterly Review 155(1975); Ind.

Eng. Chem Product ROD, 8259 (1969) and U.S. Patents No 3,637,893; 3,646,143; 3,661,144; 3,707,581; 3,707,579; 3,721,718; and 3,729,525. The resulting olefins are then oligomerized with perfluorosulfonic acid resins in the acid form.

In yet another embodiment of the invention, the olefins to be oligomerized are obtained by a multi-step process. In the first step, ethylene is transformed into linear alpha olefins using Ziegler technology as discussed above. The result of the conversion of ethylene is a mixture of alpha olefins ranging from C-4 to C-20 or even higher. The alpha olefins ranging from C-14 to C-20, or any other range of alpha olefins desired within C-14 to C-20, are separated and oligomerized using the perfluorosulfonic acid resin catalyst described above.

The alpha olefins of below 14 and above 20 carbon atoms are combined and subjected to an isomerization/disproportionation process described in the literature, for example in U.S.

Patents No 3,647,906; 3,728,414; and 3,726,938.

The olefins resulting from this isomerization/disproportionation process comprise mixture of alpha and internal olefins of various molecular weights. The olefins having from 14 to 20 carbon atoms, or any selected cut within that range, may be oligomerized with the perfluorosulfonic acid resin as above. Optionally, those olefins may be mixed with the alpha olefins from the initial ethylene made feed and oligomerized. The olefins lying outside the range to be oligomerized are combined and subjected to the isomerization-disproportionation process again. This process can be carried on indefinitely.

Such a process provides a systematic way to control which olefin cut is selected for oligomerization, and also uses the discarded cuts for additional feed.

In a further embodiment of the invention a cut comprising a-olefins having 14 to 20 carbon atoms can be separated from the product obtained by the Ziegler process from ethylere. This C14-C20 cut is then oligomerized by the process according to the invention.

We have discovered that the perfluorosulfonic acid resins in the acid form are very selective catalysts for the formation of lower oligomers of higher alpha olefins. Olefins as described above can be oligomerized with the perfluorosulfonic acid resins described above to a highly selective product distribution of dimer, trimer, tetramer, and very small amount of pentamer. Batch wise or continuous treatment yeilds oligomers which usually contain high ratios of dimer to trimer, and high ratios of trimer to tetramer.

The oligomerization generally occurs at temperatures from 60 to 250"C, preferably from 100 to 200 C. No solvent is needed. Depending on which olefins are used, there appears to be a threshold temperature at which oligomerization will proceed. Below the threshold temperature, little or no reaction occurs.

The reaction can proceed at autogenous pressures. If superatmospheric pressures are found to be advantageous, however, they are also acceptable. In a continuous process, the LHSV may vary over a wide range, and is preferably from 0.06 to 2. One skilled in the art can adjust the LHSV to suit the particular situation.

The process of the invention selectively provides valuable lower oligomers, using a solid fixed bed catalyst, requiring no hydrolosis or washing to remove the catalyst, as is the case with boron trifluoride and/or aluminium trichloride. It is surprising that such high dimer to trimer selectively occurs at good conversions, yet the reaction terminates before high molecular weight species are formed in appreciable quantities.

In order to form materials which have adequate oxidative stability for lubricants, the oligomerized olefins should desirably be hydrogenated. This hydrogenation can be carried out by procedures known to thos skilled in the art, as exemplified by U.S. Patents No 4,045,508; 4,013,736; 3,997,622 and 3,997,621. A particularly preferred catalyst for this hydrogenation is a nickel/copper/ chromia catalyst described in U.S. Patent No 3,152,998 and is referred to in this application as Ni-2715.

The invention is illustrated by the following non-limiting Examples.

The various NAFION catalysts employed in the Examples are perfluorosulfonic acid resins sold by E.l. du Pont de Nemours s Co. All are used in the acid form.

NAFION 501 is a powder NAFION 511 is a powder NAFION 520 comprises small cylinders EXAMPLE 1 To a 1000 ml round bottom (RB) flask fitted with mechanical stirrer, thermometer, Friedrich condenser, N2 inlet, dropping funnel and N2 bubbler was added 25 grams of fresh NAFION 511 ion exchange resin powder followed by 70.0 grams (0.5 moles) of decene1. The slurry was heated under a N2 pad to 85-90"C at which time the balance of the decene-1 (210.0 grams or 1.5 moles) was slowly dropped into the stirred slurry. During the decene addition, the temperature rose to 107-108"C (30 minute addition period). The mixture was heated to 120"C (required 1 5 minutes 108-120"C) and held there at 120"C- 122"C for one hour.The mixture was decanted, filtered and stripped to afford 153.0g stripped material consisting of approximately 74% C-20, 21% C-30 and 5% C-40.

Yield of higher oligomers was 54.6%; 153/280 = 54.6%.

EXAMPLE 2 To a 500 ml round bottom flask fitted as above was added 1 2. 5 grams of NAFION 511 ion exchange resin catalyst and 35g decene-1. The slurry was heated to 80"C and additional decene-1 was added (1 05.0g) over a 35 minute period with the temperature allowed to rise to 105roc only. The reaction mixture was heated to 1 20"C and held there for one-half hour. The catalyst was filtered and product stripped under full aspirator vacuum to a pot temperature of 100"C. The bottoms remaining amounted to 114.0 grams with the following analysis by LC: C-10 = 6.8%, C-20 = 70.6%, C-30 = 19.1% and C-40 = 3.4%. Amount of oligomers = 1 14.0g X 93.2% = 106.259 or yield = 106.25/140 = 75.9%.The dimer/ trimer/tetramer ratio was 20.8/5.6/ 1.0.

EXAMPLE 3 To a 500 ml flask was added 12.59 NA FION 511 resin in the acid form and 140 grams decene-1. The slurry was stirred for three days (/72 hours) at 36"C. Analysis by GPC and LC indicated no higher oligomers (20 or 30) were present, even in trace amounts (less than that detectable).

EXAMPLE 4 A mixture of NAFION 520 and glass beads on an equal volume basis was charged to a 1 inch outside diameter reactor. When decene-1 was introduced via a syringe at 46 ml/minute at a reactor hot spot temperature of 1 40 C, the conversion of decene-1 to higher oligomers was 54.4%. Carbon number distribution for the product was C-20 = 60.7%; C-30 = 20.7%; C-40 = 11%; C-SO = 5.5% based on high pressure liquid chromatography.

EXAMPLE 5 To a 250 ml RB flask was added 5.0 grams of NAFION 501 ion exchange resin in the acid form followed by 7-tetradecene (50.0 grams). The slurry was heated to 1 25 C and held there for four hours under slow N2 purge (with stirring). After filtering the catalyst, the filtrate weighed 49.3 grams (98.6% recovery). GPC analysis indicated 16.8% C-14 material, 66.8% C-28 (dimer), and 1 6.4 C-42 + traces of heavier materials. The materials had a viscosity index of 101.3 and a pour point of - 45"C. The 99"C viscosity was 2.1 7 cst. Total conversion to C-28 and heavier material was 83.2%.

EXAMPLE 6 In an experiment exactly similar to Example 5 except that the reaction temperature was 150"C, the product observed consisted of 15.6% C-14, 67.4% C-28 and 17.0% C-42.

This material had a viscosity index of 104.9 and a pour point of - 45"C and 99"C viscosity of 2.33. Total conversion to C-28 and heavier materials was 84.2%.

EXAMPLE 7 In an experiment exactly similar to Example 5 except that the temperature was 75"C, the product now consisted of 93.3% C-i4 and lights, and only 4.8% C-28, 1.9% C-42.

Total conversion to C-28 and heavier materials was only 6.7%.

EXAMPLE 8 In an experiment similar to Example 5 except that 50.0 grams of octene-2 and 5.0 grams of NAFION resin were heated at 125"C for four hours, the product we observed consisted of 1.6% C-8 and lights, and 59.7% C-16, and 38.7% C-24 and heavier.

EXAMPLE 9 In a 250ml RB flask was added 15 grams decene-5 and 6.2 grams NAFION ion exchange resin 501 in H+ form and heated to 150 C at which time 55 grams more decene5 were added over a 15 minute period. The slurry was heated for 2 hours at 150"C and filtered after cooling. The product's GPC indicated the presence of only C-20 (80.2%) and C-30 (19.8%).

EXAMPLE 10 In a round bottom flask fitted as in Example 1 was added 20 grams of fresh NAFION 511 ion exchange resin catalyst in the H + form and 42 grams of C-6 vinylidene olefin derived by dimerizing propylene in the presence of triethylaluminum catalyst in n-heptane (15% TEAL in heptane). This slurry was heated to 45"C and C-6 vinylidene olefin addition was begun (126.0 grams to be added). The addition required 24 minutes and the reaction mixture's temperature rose from 45"C to 84 C during the addition. The reaction mixture was further heated to 120"C and held between 110-120 C for two hours.After filtering and stripping at aspirator vacuum, the bottoms weighed 118.0g. Per cent recovery = 118/168 = 70.2%. Analysis of the stripped material by LC indicated /1.1% lights, 39.4% C-12 (dimer) 57.9% C-18 (trimer and tetramer), and 1,5% heavier materials. Yield of dimer, trimer, and tetramer= 68.4%.

EXAMPLE Ii Similarly to Example 10, 25 grams of NA FION 511 was charged to flask along with 56.9 grams of C-8 vinylidene olefin derived by dimerizing butene-l in the presence of triethylaluminum catalyst. This slurry (NA FION + C-8 vinylidene olefin) was heated to 82"C at which temperature the balance of the C-8 vinylidene olefin (168.9 grams) was added dropwise from 82-98"C over a 26 minute period. The reaction mixture was heated steadily over a one-hour, seventeen minute period. The lights were caught in the dropping funnel in order to increase the pot temperature.In a ten minute period, the pot temperature was increased from 105 to 1256C. Further distillation of lights (/65ml) afforded a reaction temperature maximum of 157 C (125 to 157oC over an 18 minute period). After stripping the product, recovery C-16 and C-24 was about 24-26%. Yield was /24-26% as all of the stripped material was C-16 and C-24. Hydrogenation of the oligomer mixture afforded a saturated mixture of dimer and trimer which has a viscosity index of 155.9 and pour point - 45"C and 99"C viscosity = 2.83. The above compare the properties of Al C13 catalyzed oligomers as follows.For example, the hydrogenated oligomer from C-8 vinylidene olefin (AICI3 catalysis) had a VI = 81.9, a 99"C viscosity of 5.8 and a pour point of - 30'C.

EXAMPLE 12 Similarly, C-12 vinylidene olefin (84.0 grams) was treated with 25 grams NAFION 511 followed by an additional 252 grams C-12 vinylidene olefin. Heating to 120-1 23"C for one hour afforded C-24 and C-36 oligomers in /20.2% yield with the ratio of C-24 C-26 /9- 0/1.

EXAMPLE 13 Similarly, C-16 vinylidene olefin (224 grams) was added to NAFION 511 (22.4 grams) and decane solvent (50 grams) at 108-1 O9"C. The slurry was heated to 120"C for two hours and the product stripped indicated a 38% yield of C-32 and C-48 oligomers. The ratio of C-32/C-48 was /10/1.

EXAMPLE 14 To a 1,000 ml round bottom flask was added 224 grams C-16 vinylidene olefin and 196 grams C-14 alpha olefin, followed by 42.0 grams used NAFION 511 ion exchange resin catalyst. The slurry was heated to 125"C and held there for about two hours and further heated at 125- 131 C for two hours and thirty minutes. After filtering and stripping, the recovery was 408.1 grams or 97.2% of the weight charged. The product consisted of 87-813% material C-14 or C-16 molecular weight range, likely unreacted starting material. There was also some 12% material with molecular weight C-30 in the GPC analysis, indicating combination of the C-14 alpha and C-16 vinylidene olefin. A further small peak occurred where the C-32 molecular weight was expected (C-16 vinylidene olefin + C-16 vinylidene olefin).

Similarly, 224 grams 2.0 moles of C-8 vinylidene olefin and 146 grams of C-14 alpha olefin (1.0 mole) were combined with 47.0 grams of used NAFION 511 ion exchange resin catalyst and the slurry was heated at 99-112" for 1i hours. It was then heated at 112-125 C for two hours and finally from 125-133"C for one hour. After filtering and stripping, the weight of recovered material was 75% basis the weight changed.

GPC analysis of the stripped material indicated some 16-17% material in the C-22 to C-24 range, the C-22 material apparently resulting from reaction of the C-8 vinylidene olefin and C-14 alpha olefin. The C-24 material was apparently a C-8 vinylidene olefin trimer. This reaction is poor compared with the following example, demonstrating the importance of choosing proper conditions in each case.

EXAMPLE 15 To a 500 ml round bottomed flask was added 43.2 grams of NAFION 511 catlayst (used previously three times) followed by 72.0 grams of a mixture of C-6, C-7 and C-8 vinylidene olefin made by dimerizing a 1/1 molar mixture of propylene and butene-1 using triethylaluminum (TEAL) in hexane (15% TEAL in hexane) and 72 grams of C-14 alpha olefin and 72 grams of C-16 alpha olefin. The mixture was heated over a 2 hour period (slowly) to 150"C and held there for 9+ hours. GPC indicated 63.3% material C-30 or higher molecular weight. Hydrogenation of the above mixture (Ni 271 5 catalyst) was carried out at 210"C for 4 hours at 140 bars H2 pressure.High vacuum distillation (after catalyst filtration) afforded 62.6% bottoms product with a 4.85 cst viscosity at 99"C and VI = 82.1 and pour point of - 40"C.

EXAMPLE 16 To a 1-liter RB flask was added 189 grams of a mixture of 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene (39.5% C-14, 27.1% C-16, 19.8% C-18, 13.6% C-20, this is the approximate weight ratio which these olefins would be made from an alpha olefin plant operating at 0.6b) and 24.0 grams NAFION 501 ion exchange resin catalyst in the H + form. the reaction mixture was stirred at 150"C for 4 hours. The catalysts was removed by filtration and the GPC indicated a 60% conversion to C-28 and heavier materials.

EXAMPLE 17 To a l-liter stainless steel autoclave was charged 1 89 grams of oligomer made in Example 16 and 9.45 grams Ni-2715 catalyst in the powder form. The mixture was hydrogenated at 210"C for 4 hours at 140 bars hydrogen pressure. The catalyst was removed by filtration and the monomers removed by high vacuum stripping at 1-1.3 mm pressure to a pot temperature of 222"C (OH temp. of approximately 167"C). The amount of recovered bottoms product oligomer was 73.8 grams (or 51.1% of the amount charged to stripping apparatus).The properties of the stripped hydrogenated bottoms product were outstanding and listed below: Viscosity, 99"C = 5.22 cst VI = 114.2 Pour Point = - 40'C Volatility was good with 96.9% of the sample remaining at 194"C and 88.9% of the sample remaining at 233"C EXAMPLE 18 To a 1000 ml RB flask fitted with mechanical stirrer and condenser, N2 inlet and bubbler, and thermometer was added 500.0 grams of 1-hexadecene and 25.0 grams of NAFION ion exchange resin catalyst (501 powder) in the H + form. The reaction mixture was heated a to 150"C and held there for four hours. The catalyst was removed by filtration.

Gel permeation indicated 71.8% conversion to C-32 (dimer) and heavier species (mainly trimer). The dimer/trimer ratio was 6.7/1.

EXAMPLE 19 To a l-liter stainless steel autoclave was added 476.3 grams of oligomer made in Example 18 above and 23.8 grams of Ni 271 5 catalyst (5%). The hydrogenation was conducted for two hours at 190"C and 140 bars of hydrogen pressure. The oligomer (after catalyst was removed by filtration) was stripped at high vacuum (0.4-0.5 mm) to a pot temperature of 213-215"C (held there for one hour and 20 minutes).The bottoms product amounted to some 62.1 % of the total recovered material (overhead + bottoms) and had the following excellent properties: 99 viscosity = 5.09 cst VI = 112.3 Pour Point = - 45'C Volatility was very low: 97.9% of sample remained at 194"C 91.2% of sample remained at 233"C EXAMPLE 20 To a 5000 ml Morton RB flask was added 15979 of octadene-l and 31.9 g of NAFION 501 ion exchange resin catalyst in the H +form. The mixture was heated under N2 and stirred mechanically with the reaction mixture held at 150"C for approximately 67.0 hours. The catalyst was removed by filtration; GPC indicated a 72.2% conversion to C-36 and heavier materials.

EXAMPLE 21 To a one gallon stainless steel autoclave was charged 1 401 grams of oligomer made in Example 20 and 70.0 grams of Ni-2715 catalyst. The hydrogenation was conducted at 140 bars pressure and 190"C temperature for four hours.The catalyst was removed by filtration and the hydrogenated oligomer stripped at high vacuum (0.35-0.45mm) and to a pot temperature of 218"C (30 minutes at 198-218"C). The bottoms product oligomer had the following excellent properties: Viscosity, 99"C= 6.24 cst VI = 119.6 Pour Point = - 30'C Volatility excellent: 97.7% sample remained at 194 C 92.6% sample remained at 233"C EXAMPLE 22 To a 500 ml RB flask fitted with mechanical stirrer, N2 inlet and bubbler, thermometer, condenser, and dropping funnel was added 1 9.6 grams NAFION 501 ion exchange resin powder in the H + form followed by SO grams of n-decane solvent.The reaction flask was purged with N2 and heated to about 110"C where 1 96 grams (1.0 mole) of tetradecene-l was dropped in slowly over a one hour period during which time the temperature was very gradually increased to 115"C. The reaction mixture was heated further for 2 hours and 15 minutes, slowly increasing the temperature to 125"C. The reaction was at 125"C for approximately 2 hours. The oligomer was subjected to hydrogenation in Example 23 below.

EXAMPLE 23 To a 1-liter stainless steel autoclave was added 147.2 grams of crude oligomer (after catalyst removed by filtration) made in Example 22 along with 7.4 grams of Ni-2715 catalyst (ground up). The oligomer was hydrogenated at 140 bars H2 pressure and 210 C for 4 hours. The Ni-27 1 5 catalyst was removed by filtration and the water white oligomer distilled at high vacuum to afford 51.3 grams of bottoms product. The properties of the hydrogenated bottoms product oligomer included: 99"C viscosity of 4.03 cst, pour point of - 45"C and VI = 106.4.Volatility was very low: 98.6% of sample remained at 194"C and 92.3% remained at 233"C. Liquid chromatography indicated that the bottoms product consisted of 80.5% C-28 (dimer), 16.7% C-42 (trimer) and only 2.8% C-56 (tetramer).

EXAMPLE 24 To a 1000 ml round bottom flask equipped with mechanical stirrer, thermometer, 2 inlet, and Friedrich condenser, was added 300 grams C-l 5/C-18 wax cracked olefins (C-14 = 2.0%, C-15 = 30.0%, C-16 = 30.0%, C-17 = 28.0%, C-18 = 10.0%, C-19 = 0.1%) and 30 grams NAFION 501 ion exchange resin in the H+ form (10.0 wt.% of olefin charged). The mixture was heated at 150"C with stirring under a N2 pad for 5 hours. The catalyst was removed by filtration.

GPC (LC) data showed 66% (70%) conversion to dimer and trimer.

EXAMPLE 25 An autoclave was charged with 325.0 grams of feed obtained by the procedure of Example 24 followed by 16.3 grams Ni 2715 catalyst (5.0 wt.% of olefin charged). The crave was flushed with H2 three or four times.

The crave was pressured to 70 bars with H2, and heated to 210 C. The crave was repressured to 140 bars heated and stirred at 210"C for four hours, repressuring as necessary. The hydrogenated product was cooled and poured up. Ni-2715 was removed by filtration.

EXAMPLE 26 The hydrogenated product of Example 25 was stripped under high vacuum (1.5mm Hg) to a pot temperature of 215"C to remove unreacted starting materials. 59% of the amount of oligomer/monomer charged was recovered as dimer/trimer. The resulting synlube gave the following properties: 99"C vis = 5.63 cs; VI = 110.7, pour point = - 40"C; thermal properties, 98% remaining at 194"C, and 92.3% remaining at 233"C.

EXAMPLE 27 A 228 gram sample of C-l 3/C-14 paraffin was combined with 22.8 grams C-13/C-14 internal olefin (Shell, 10% by weight of paraffin) in a 500 ml round bottom flask equipped with magnetic stirrer, thermometer, N2 inlet, and Friedrich condenser. To this mixture was added 1.1 grams of NAFION 501 ion exchange resin in the H+ form (duPont, 5.0 wt.% of olefin charged). The reaction mixture was heated to 150"C and stirred for 12 hours under a N2 pad. GPC analysis showed 40-50% conversion of the olefin charged to dimer/trimer.

EXAMPLE 28 245 grams of mixture obtained above was charged to a 500 ml round bottom flask equipped with magnetic stirrer and thermometer. The paraffin and monomer were stripped under O.4mm high vacuum to a pot temperature of 160"C. GPC analysis of the bottoms product showed a dirneritrimer ratio of 94% dimer, 6% trimer, or 15.5/1.

EXAMPLE 29 A C-i 13 /C- 14 olefin mix oligomerized with- out the presence of paraffin gave the following properties after hydrogenation and stripp ing.

viscosity 99"C, cs = 4.08 VI = 90.3 Pour Point = - 45"C 94.6% sample remained at 144"C, 77.3% sample remained at 233"C.

EXAMPLE 30 A mixture composed of 7-tetradecene (50.0 grams) and NAFION 501 (5.0 grams) was stirred at 125"C for four hours under nitrogen purge. Filtration afforded 49.3 grams (98.6% recovery) of a material which consisted of 16.8% C-14, 66.8% C-28, and 16.4% C-42 materials basis GPC analysis.

EXAMPLE 31 Repeating the preceding experiment at 150"C provided a material exhibiting the following analysis: 15.6% C-14; 67.4% C-28; 17.0% C-42 (basis GPC) EXAMPLE 32 In a similar manner, 1 5 grams A5-decene and 6.2 grams NAFION were heated to 105"C at which time 55 grams b5-decene was added over 15 minutes. The resulting mixture was stirred at 150"C for two hours.

Filtration provided a product which consisted of C-20 (80.2%) and C-30 (19.8%) components on a monomer-free basis.

EXAMPLE 33 Crude reaction products prepared by oligomerizing 7-tetradecene with 10-20% NA FION 501 powder(H+ form) at 125-150"C (4 hours), freed of NAFION catalyst were combined then hydrogenated at 210"C for four hours in the presence of 5 wt.% Ni-2715 catalyst and 1 40 bars pressure.Filtration of this material followed by removal of lights (monomer) gave a lubricant exhibiting the following physical properties: K. viscosity, cst 99"C 4.52 Pour point - 40"C VI 105 EXAMPLE 34 To a 1000 ml RB flask fitted with mechanical stirrer, condenser, N2 inlet and bubbler, and thermometer were added 500 grams of Shell's C-13/C-14 mixed internal olefins' 53.4% C-13, 45.0% C-14, 0.5% C-15, and 1.1% hydrocarbon and 5.0 grams of NAFION 501 ion exchange resin catalyst in the H+ form. The reaction mixture was heated at 150"C with stirring for 1 9-3/4 hours. The catalyst was removed by filtration.Gel permeation chromatography indicated conversion to C-26 and higher carbon oligomers was approximately 83.6% (C-13/C-14 = 16.4%, C-26/27/28 = 69.1%, C-39/40/41/42 = 14.5%).

'Similar olefin mixtures are obtained by the isomerization/disproportionation process disclosed heretofore.

EXAMPLE 35 To a 1-liter stainless steel autoclave was added 300.0 grams of oligomer made in Example 34 and 15.0 grams of Ni-2715 catalyst in powdered form. The reaction mixture was stirred at 210"C in the presence of 1 40 bars hydrogen pressure for four hours.

The catalyst was removed by filtration and the clear, nearly water-white fluid had the following desirable properties after removal of monomer under high vacuum stripping to a pot temperature of 180"C.

Viscosity 99"C. cst = 3.93 VI = 92.3 Pour point = - 45"C Three hydrogenations were completed on three different oligomers from Shell's C-13/ C-14 internal olefin mixture and the hydrogenated lubricant after removal of monomer had viscosities in the range of 3.9-4.5 cst at 99"C, viscosity indices in the 90-95 range and pour points which ranged from - 40 to - 45"C. Volatilities were also good, with 93-95% sample remaining at 194"C and 74-78% remaining at 233"C.

EXAMPLE 36 To a l-liter RB flask was added 1 89 grams of a mixture of 1-tetradecene, 1-hexadecene, 1-octadecene, and 1 -eicosene (39.5% C 14, 27.1% C-16, 19.8% C-18, 13.6% C-20, this is the approximate weight ratio which these olefins would be made from an alpha olefins plant operating at 0.6p) and 24.0 grams NAFION ion exchange resin catalyst in the H+ form. The reaction mixture was stirred at 150"C for 4 hours. The catalyst was removed by filtration and the GPC indicated a 60% conversion to C-28 and heavier materials.

EXAMPLE 37 To a l-liter stainless steel autoclave was charged 1 89 grams of oligomer made in Example 36 and 9.45 grams Ni-2715 catalyst in the powder form. The mixture was hydrogenated at 210"C for 4 hours at 140 bars hydrogen pressure. The catalyst was removed by filtration and the monomers removed by high vacuum stripping at 1-1.3 mm pressure to a pot temperature of 222"C (OH temp. of approximately 167"C). The amount of recovered bottoms product oligomer was 73.8 grams (or 51.1 % of the amount charged to stripping apparatus). The properties of the stripped hydrogenated bottoms product were outstanding and listed below: Viscosity 99"C = 5.22 cst VI = 114.2 Pour point = - 40"C Volatility was good with 96.9% of the sample remaining at 194"C and 88.9% of the sample remaining at 233"C.

Claims (20)

1. A process for oligomerizing an olefin having at least 10 carbon atoms by contacting the olefin with a catalyst, wherein the catalyst comprises a perfluorosulfonic acid resin.

2. A process as claimed in Claim 1 wherein the perfluorosulfonic acid resin has as equivalent weight of from 1100 to 1 500.

3. A process as claimed in claim 1 or 2 wherein the oligomerized product is hydrogenated.

4. A process as claimed in any of claims 1 to 3 wherein the olefin is an a-olefin having 10 to 20 carbon atoms.

5. A process as claimed in any of claims 1 to 3 wherein the olefin is an internal monoolefin having 10 to 28 carbon atoms.

6. A process as claimed in any of claims 1 to 3 wherein the olefin is a vinylidene olefin having 10 to 32 carbon atoms.

7. A process as claimed in any of claims 1 to 3 wherein the olefin comprises a mixture having 1 3 to 20 carbon atoms obtained by wax cracking of paraffins.

8. A process as claimed in any of claims 1 to 3 wherein the olefin comprises a mixture obtained by dehydrogenating a mixture of linear paraffins having 1 3 to 20 carbon atoms.

9. A process as claimed in any of claims 1 to 3 wherein the olefin comprises mono olefins having an even number of carbon atoms in the range from

10 to 1 8 obtained by disproportionating linear a-olefins having up to 10 carbon atoms, isolated from a mixture resulting from the polymerization of ethylene.

1 0. A process as claimed in any of claims 1 to 3 which comprises: (i) polymerizing ethylene to a mixture of a- olefins, (ii) isolating and oligomerizing a-olefins having 14 to 20 carbon atoms from the product of step (i) (iii) isomerizing/disproportionating olefins from step (i) having less than 14 and more than 20 carbon atoms, and (iv) isolating and oligomerizing a-olefins having 14 to 20 carbon atoms from the product of step (iii).

11. A process as claimed in claim 10 wherein (v) olefins from step (iv) having less than 14 and more than 20 carbon atoms are isomerized/disproportionated, and steps (iv) and (v) are repeated at least once.

1 2. A process as claimed in any of claims 1 to 3 wherein the olefin comprises a-olefins having 10 to 20 carbon atoms isolated from a mixture obtained by polymerizing ethylene.

1 3. A polyolefin composition obtained by a process as claimed in any of claims 1 to 1 2.

1 4. A lubricant composition which comprises a polyolefin as claimed in claim 1 3.

1 5. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 1 to 23.

1 6. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 24 to 26.

1 7. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 27 to 29.

18. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 30 to 33.

1 9. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 34 and 35.

20. A process as claimed in claim 1 and substantially as hereinbefore described with reference to any of Examples 36 and 37.