US2422991A

US2422991A - Production of hydropolymers

Info

Publication number: US2422991A
Application number: US425861A
Authority: US
Inventors: Strang Leslie Christopher
Original assignee: Anglo Iranian Oil Co Ltd
Current assignee: Anglo Iranian Oil Co Ltd
Priority date: 1940-12-23
Filing date: 1942-01-07
Publication date: 1947-06-24
Anticipated expiration: 1964-06-24

Description

Patented June 24, 1947 PRODUCTION OF HYDROPOLYMERS Leslie Christopher Strang, Sunbury-on-Thames,

England, assignor, by mesne assignments, to Anglo-Iranian Oil Company Limited, London,

England, a company No Drawing. Application January 7, 1942, Serial 4 Claims.

This invention relates to the production of aviation or motor spirit of high octane number.

Isoparafiinic materials produced in the nondestructive hydrogenation of the product of polymerisation of mixtures of isobutene and normal butenes are valuable components of aviation spirit of high octane number. These isoparaffinic materials have high octane numbers of 91- 96 (C. F. R. motor method), depending upon the proportions of isobutenes and normal butenes polymerised, but they have the disadvantage that they boil substanially at or above 100 C. Whereas finished aviation spirits are normally required to contain at least 50% boiling below 100 C. Blends of aviation spirit containing such materials must also contain a. considerable quantity of volatile constituents that are often of low 00. tane number.

It is among the objects of the invention to produce hydrogenated polymers from an olefinic feedstock consisting of or containing mixtures of isobutene and normal butenes, the hydrogenated polymer products having a considerably increased volatility at 100 C. with no loss in octane number and a range in octane numbers varying according to the operating conditions in polymerisation particularly with respect to temperature and throughput.

According to the invention in a process for the production of isoparaflins by the non-destructive hydrogenation of the polymerisation products of isobutene and normal butenes together or contained in or derived from a butane-butene fraction or other source of isobutane and normal butenes, propene is added to the olefinic feedstock of the polymerization plant or unit in a proportion determined according to the content of isobutene in the olefine feedstock. Thus the.

butane-butene fraction that may be used may have a normal butenes-isobutene ratio in the range 1.5 to 1 to 25:1. To obtain a polymer or hydropolymer distillate to 120 C. which has approximately a 50% volatile content to 100 C. on an A. S. T. M. distillation, the amount of propene to be added for any given content of isobutene is in the range of 60130% wt. of the isobutene content, and the operating conditions of throughput and temperature are determined to obtain the polymer necessary to yield the desired octane number of the hydropolymer. This temperature shouldbe in the range 130-250 C., but more usually in the narrower range 150- 190 C. to obtain an octane number of 90 or higher than 90 for the hydropolymer.

The operating pressure is in the range 250 In Great Britain December 23,

1400 lbs/sq. in. Thus the desired volatile hydropolymer is obtained in one polymerisation operationv and is not dependent upon the separate interpolymerisation of propene and iso- 5 butene.

The invention comprises the conditions hereinafter described.

In carrying the invention into effect a proportion such for example as 12% of propene may be added to the feed to the catalytic polymerisation plant or unit. This plant or unit may operate for example at 1400 lbs/sq. in., and at a temperature of about 160 C. whereby a suitable polymer and ultimately a hydrogenated polymer may be produced under conditions substantially as hereinafter described. 7

The following are examples of process conditions as to which the expression S. C. F., as used hereinafter, shall mean standard cubic feet. 20

Example 1 Feed composition (including added propene):

Weight per cent C2 hydrocarbons 0.2 CsHs 8.0 CsHs 12.0 C4H1o 30.5 iSO-C-1H8 16.1 n-C4Ha 32.2 C5 hydrocarbons 1.0

Operating conditions in polymerisation:

Catalyst Copper phosphate, cadmium phosphate and phosphoric acid. Pressure 1400 lbs/sq. in. Temperature 160 C. Feed rate s. o. F./lb.

catalyst/houn--- circa 20 Wt. per cent conversion to polymer on feed--- 26.5

Polymer composition:

Volume percent 10-100 C 40.3 -120" C 48.4 50 Above c 11.3

This polymer has the same volume per cent. residue above 120 C. (circa 11%) as that produced from a feed consisting solely of C4 hydrocarbons.

3 The product of the non-destructive hydrogenation of the 10 C.-120 C. fraction had the following characteristics: Octane number (C. F. R. motor method) 94.0 A. S. T. M. volatility at 100 C. per cent 40 There is thus no substantial loss in octane number of the hydrogenated polymer and the volatility at 100 C. is considerably increased.

Exampl 2 C3Hs 6.6 C3He 18.2 C4H10 27.3 iSO-C4Hs 15.8 Xl-C4H8 29.0 C5 hydrocarbons 3.1

Operating conditions in polymerisation:

Catalyst As in Example 1 Pressure. 1400 lb./sq. in.

Feed rate S. C. F./lb./catalyst/hour circa 18- The following table indicates yields, composition and characteristics of the products at varying, temperatures employed in the polymerisation of the material under the operating conditions lndicated.

Temperature, C 160 190 225 Yields Wt. Percent 011 Feed:

Total Polymer 24.1 32.1 43.0 Distillate to 120 C 20. 6 25. 6 29. Hydrogenated Polymer:

Vol. percent 01H and under 36 36 32 Vol. percent 0 H 53 46 39 Vol. percent OnHm and over 11 18 29 Vol. percent Distillate to 120 C. on feed 86. 2 81. 2 69. 6 Hydrogenated Distillate to 120 0.:

Octane No. (C. 1 2R M. M. 92. 4, 01. 2. 86. 2 -A. S. T. M. volatility at 100 0., percent 50 52. 50 Oetane'N'o. (C: F. R. M. M.):

0 11 cut 9.0..7 88. 6. 84. 5 C511 cut 95. 8 93. 4 87.0

A comparison of Examples 1 and 2 shows that an increase in the propene content from 12% to 18% results in a lower octane number of hydrogenated distillate to 120 C. when operating under the'same. conditions, i. e. 160 C., 1400 lbs/sq. in. pressure and a throughput of 18-20 S. C. F./lb. catalyst/hour.

Under the conditions set out in the, table of Example 2 change in yield of the hydropolymer is obtained by increasing the temperature, but it will be understood that change in yield may also be achieved by change in the feed rate which under the conditions of the table. of Example 2 is the same in each case.

Example 2 shows how an increase in operating temperature results in an increased yield of total polymer, 2. higher percentage of heavy polymer in'thetotal polymer, and lower octane number of. thehydrogenated polymers. Both the C'lHlG and C8H18 cuts. show, reduced octane number with increasing operating temperature. Thus the operating polymerisation. temperature must be kept. sufficiently. low to produce a hydrogen.- ated aviation spirit ofithe desired. octane, number.

A suitable feedstock may conveniently be obtained in one operation in the secondary fractionation of the overhead, operating upon cracked petroleum distillates, instead of the hutane-butene fractions being used as the source of the olefine feedstock.

Polymerisation catalysts consisting of cadmium di-hydrogen ortho-phcsphate or cadmium copper di-hydrogen ortho-phosphate in a solid, hard, dry and porous state respectively prepared from cadmium ortho-phosphate and ortho-phosphoric acid and from copper ortho-phosphate, cadmium ortho-phosphate and ortho-phosphoric acid may be produced and used in the manner described in the specification of the prior United States Patent No. 2,128,126, while polymerisation catalysts prepared from copper orthophosphate, calcium ortho-phosphate and orthophosphoric acid may be produced in a solid, hard, dry and porous state and used. A proportion of steam is added to the stream of olefine feedstock in a proportion of from 4 to 10% by volume according to known practice to maintain the activity of the catalyst. Any other polymerisation catalysts than those specified may however be used, but those specified are preferred.

In the foregoing examples the polymers were hydrogenated over a catalyst consisting of mixed nickel and tungsten sulphides at a hydrogen pressure of 1000 lbs/sq. in. at a temperature of 250 C. and throughput of about 0.5 volume polymer/volume catalystlhour.

I claim:

1. A process for the production of isoparaffins from olefins comprising catalytically polymerising an olefinic feedstock at a temperature of from 160 to 190 C. and non-destructively catalytically hydrogenating polymer products of the polymerisation reaction, the said feedstock comprising normal butenes and isobutene in a normal butenes-isobutene ratio in the order of 1.511 to 2.5.21v and, propene in a, proportion in the order of 60% to 130% wt. on the isobutene content of the feedstock.

2; The process of. claim 1 in which the polymerising reaction is carried out at a temperature of from 160 to 190 C., and at a pressure in the order of 250 to 1400 lbs. per sq. in., to yield on the hydrogenation of the polymer product a hydropolymer product having an octane number of not lessv than 90.

3;. The process of claim 1 in which the hydrogenation reaction is, carried out with a nickeltungsten sulphide catalyst, under a hydrogen pressure in the order of 1000 lbs. per sq. in., at a temperature of the order of 250 C., and a throughput of the order of 0.5 volume polymer per volume catalyst per hour.

4. A process for the production from C3 and C4 olefines of an isoparafiinic hydropolymer distillate to 120 C. having an octane number of at least and a proportion volatile to C. of the order of. at least 50% and adapted for use as an aviation or motor spirit comprising catalytically polymerising normal butenes and isobutene in a normal butenes-isobutene ratio in the order of 2:1 together with propene in a proportion in the order of 75 to Wt. of the isobutene, at a temperature; in the order of C'., a pressure in the order of 1400 1bs. per sq. in. and a feed rate in the ing a hydrogenated distillate to 120 C. as the Number desired product. 2,172,542 LESLIE CHRISTOPHER STRANG. 2,245,143 2,255,275 REFERENCES CITED 5 2 2 2 304 The following references are of record in the 22712942 file of this patent: 2,128,126 2,135,823 UNITED STATES PATENTS Number Name Date 10 2,181,640 Deanesly et a1 Nov. 28, 1939 Number 0, Ipatieff et a1 Jan. 20, 1942 501,325 2,181,942 Ipatieff et a1. Dec. 5, 1939 Name Date Morrell Sept. 12, 1939 Gerhold June 10, 1941 Stahly Sept. 9, 1941 Jean Nov. 18, 1941 Keunecke et a1 Feb. 3, 1942 Dunstan Aug. 23, 1938 Lyman Nov. 8, 1938 FOREIGN PATENTS Country Date Great Britain Feb. 24, 1939