US3705093A

US3705093A - Refined heavy alkylate bottoms oil

Info

Publication number: US3705093A
Application number: US153119A
Authority: US
Inventors: Thomas L Ashcraft Jr
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1971-06-14
Filing date: 1971-06-14
Publication date: 1972-12-05
Anticipated expiration: 1989-12-05

Abstract

A COLORLESS AND ODORLESS SPECIALTY OIL HAVING A VISCOSITY WITHIN THE RANGE FROM ABOUT 75 SSU TO ABOUT 3000 SSU AT 100*F., A VISCOSITY INDEX WITHIN THE RANGE FROM ABOUT 0 TO ABOUT -200, AND AN AROMATICS CONTENT COMPARABLE TO THAT OF WHITE OILS IS PREPARED BY HYDROGEN REFINING AND THEN DYDROGENATING A HEAVY ALKYLATE BOTTOMS OIL OF APPROXIMATELY THE SAME VISCOSITY AND VISCOSITY INDEX WHICH HAS A BOILING RANGE WITHIN THE LIMITS FROM ABOUT 540*F. TO ABOUT 800*F. THE HEAVY ALKYLATE OIL CONTAINS AT LEAST ABOUT 90 WEIGHT PRECENT SATURATED HYDROCARBONS, WHICH ARE ABOUT 50 TO 70 WEIGHT PERCENT NAPHTHENES, THE REMAINDER BEING ISOPARAFFINS. THESE SATURATED MOLECULES HAVE HIGHLY BRANCHED SIDE CHAINS WHICH ARE CHARACTERIZED BY A HIGH "BRANCHINESS RATIO" OF FROM ABOUT 2.6 TO ABOUT 3.9 THE NAPHTHENES ARE PREDOMINANTLY POLYCYCLIC AND HAVE A BICYCLIC RATIO OF FROM ABOUT 0.4 TO ABOUT 0.8. HYDROGEN REFINING OF THE HEAVY ALKYLATE OIL IS CARRIED OUT IN THE PRESENCE OF A SULFUR-INSENSITIVE CATALYST AT A TEMPERATURE FROM ABOUT 400*F. TO ABOUT 700*F. UNDER A HYDROGEN PRESSURE FROM ABOUT 150 TO ABOUT 2000 P.S.I.G. USING A HYDROGEN-TREAT RATE FROM ABOUT 100 TO ABOUT 1000 S.C.F./BBL. AT A LIQUID HOURLY SPACE VELOCITY FROM ABOUT 0.1 TO ABOUT 10. HYDROGENATION OF THE HYDROGENREFINED HEAVY ALKYLATE OIL OCCURS IN A HYDROGENATION ZONE OVER A GROUP VIII METAL HYDROGENATION CATALYST AT TEMPERATURES FROM ABOUT 300*F. TO ABOUT 650*F., A HYDROGEN PRESSURE FROM ABOUT 300 TO ABOUT 3000 P.S.IG., A LIQUID HOURLY SPACE VELOCITY FROM ABOUT 0.1 TO ABOUT 3.0 V./V./HR., AND A HYDROGEN-TREAT RATE FROM ABOUT 300 TO ABOUT 2500 S.C.F./BBL. THE HYDROGENATED OIL IS USEFUL AS A UNIQUE COSMETIC BASE OIL.

Description

Dub 1972 "r. L. ASHCRAFT, JR 3,105,093

REFINED HEAVY ALKYLATE BOTTOMS OIL Filed June 14, 1971 HYDROGEN R-EFINING l6 5 I ZONE HEAVY AL l YhATE BOTTOMS HYDROGENATION ZONE 4 OIL USEFUL AS COSMETIC OIL INVENTOR. THOMAS L. ASHCRAFT,

AT ORNEY.

United States Patent O U.S. Cl. 208-14 17 Claims ABSTRACT OF THE DISCLOSURE A colorless and odorless specialty oil having a viscosity within the range from about 75 SSU to about 3000 SSU at 100 F., a viscosity index within the range from about to about -200, and an aromatics content comparable to that of white oils is prepared by hydrogen refining and then hydrogenating a heavy alkylate bottoms oil of approximately the same viscosity and viscosity index which has a boiling range within the limits from about 540 F. to about 800 F. The heavy alkylate oil contains at least about 90 weight percent saturated hydrocarbons, which are about 50 to 70 weight percent naphthenes, the remainder being isoparaffins. These saturated molecules have highly branched side chains which are characterized by a high branchiness ratio of from about 2.6 to about 3.9. The naphthenes are predominantly polycyclic and have a bicyclic ratio of from about 0.4 to about 0.8. Hydrogen refining of the heavy alkylate oil is carried out in the presence of a sulfur-insensitive catalyst at a temperature from about 400 F. to about 700 F. under a hydrogen pressure from about 150 to about 2000 p.s.i. g. using a hydrogen-treat rate from about 100 to about 1000 s.c.f./bbl. at a liquid hourly space velocity from about 0.1 to about 10. Hydrogenation of the hydrogenrefined heavy alkylate oil occurs in a hydrogenation zone over a Group VIII metal hydrogenation catalyst at temperatures from about 300 F. to about 650 F., a hydrogen pressure from about 300 to about 3000 p.s.i.g., a liquid hourly space velocity from about 0.1 to about 3.0 v./v./hr., and a hydrogen-treat rate from about 300 to about 2500 s.c.f./bbl. The hydrogenated oil is useful as a unique cosmetic base oil.

CROSS-REFERENCE TO RELATED APPLICATION This is a continuation-in-part application of Serial No. 11,606 filed Feb. 16, 1970 and now abandoned, entitled Refined Heavy Alkylate Bottoms Oil.

BACKGROUND OF THE INVENTION This invention is directed to specialty oils which are useful as cosmetic oils and methods of producing such oils. More particularly, the invention concerns the hydrogen treatment of a heavy alkylate bottoms oil having a boiling range within the limits from about 540 F. to about 800 F., a viscosity index within the range from about 0 to about 200, and a viscosity within the range from about 75 SSU to about 3000 SSU at 100 F.

Heretofore, specialty oils used as cosmetic base oil have been prepared from virgin fractions of paraffinic and naphthenic distillates by acid treatments, hydrogen treatments, or both. The viscosities of these oils have ranged from about 75 SSU and lower up to about 500 SSU at ice 100 F., the lowest viscosity indexes being about 70. Also, specialty oils characterized as colorless and odorless have been produced from heavy alkylate oils boiling in the range from 450 F. to 650 F. and having a viscosity at 100 F. of 48 and 52 SSU, as in U.S. Pat. 3,121,678. Heretofore, however, no specialty oil usable as a cosmetic oil base has been prepared from heavy alkylate bottom oils which have a boiling range within the limits from about 540 F. to about 800 F., and which, I have discovered, have highly unusual viscosity characteristics for an oil essentially composed, as I have found them to be, of saturated hydrocarbons. These unusual characteristics are a viscosity within the range from about 75 SSU to about 3000 SSU at 100 F. and a viscosity index of from about 0 to about 20().

SUMMARY OF THE INVENTION In brief, my invention involves a two-stage hydrogen treatment of a heavy alkylate bottoms oil having a boiling range within the limits from about 540 F. to about 800 F., a viscosity within the range from about SSU to about 3000 SSU at 100 F., and a viscosity index within the range from about 0 to about -200. The oil is first hydrogen refined under certain prescribed conditions, hereinafter detailed, in the presence of a sulfur-insensitive catalyst to remove sulfur and nitrogen in the oil. Thereafter, it is hydrogenated in the presence of a Group VIII metal catalyst under hydrogenation conditions, hereinafter described which produce a colorless and odorless oil with very low aromatic compound content and possessing the unusual viscosity characteristics of the heavy alkylate bottoms oil from which it is prepared, making the oil so produced particularly useful as a unique cosmetic base oil.

The heavy alkylate bottoms oil employed The heavy alkylate bottoms oils employed in my invention are a by-product of the well-known acid (usually sulfuric acid) catalyzed isobutane or isopentane alkylation of C to C olefins, being the portion remaining after the alkylation reaction products are fractionally distilled to recover the products boiling below about 540 F. These heavy alkylate bottoms oils generally distill in an ASTM D-1l60 distillation above about 540 F. and below about 800 F., corrected to atmospheric pressure.

The heavy alkylate bottoms oils exhibit unusually high viscosities at 100 F. compared to saturated hydrocarbon fractions produced from virgin stock which have equal average molecular weights and which boil over the same ranges. In addition, the viscosity of the heavy alkylate bottoms oils varies strongly with temperature. The vis cosity index of these bottoms oils is very low compared to that of virgin oils. All of this is illustrated by Table I, hereinbelow, which sets out the viscosity and viscosity indexes of the approximately percent overhead fractions of a heavy alkylate oil boiling over a total boiling point range from about 500 -F. to about 750 F. Table I also sets out the average molecular weight of the overhead fractions as determined by vapor pressure osmometry using a toluene solvent. In addition, the API gravity at 60 F. of each fraction is indicated, and comparative nomagraph figures for composite virgin stocks of like gravity are set out.

TABLE I Heavy alkylate bottoms oil Virginstock Mean Boiling average Volume Viscosity, point range Average API boiling Viscosity percent, SSU at (initialmolecular gravity at point, SSU at OIH 100 F. V.I. final) F. weight 60 F. F 100 F.

NOTE-65 plate vacuum still. Reported boiling points corrected to atmospheric pressure.

Table I shows that the viscosities of heavy alkylate bottoms oils vary from about 50 SSU to about 3000 SSU to 100 F. over a very narrow total boiling range, or viewed another way, it shows that the heavy alkylate bottoms oils have exceptional volatility for this range of viscosities at 100 F. Table I further indicates how the viscosity index of heavy alkylate bottoms oils strongly decreases with increasing average molecular weight of the fraction. Viscosity indexes as low as -140 to --200 occur in the higher molecular weight fractions.

A heavy alkylate bottoms oil boiling above about 540 F. and below about 800 F. is comprised of at least 90 weight percent of saturated hydrocarbons, which are 50 to 70 weight percent naphthenes, the remainder of the saturated hydrocarbons being isoparafiins. A typical composition of a heavy alkylate bottoms oil having an N.B.P. range at 10 volume percent distilled of 616 F., at 50 volume percent distilled at 666 F., and at 85 volume percent distilled of 728 F. is illustrated in Table II. The composition was determined by a mass spectrographic analysis made on silica gel separated portions of the oil.

TABLE II.TYPICAL COMPOSITION OF HEAVY ALKYLATE BOTTOMS OIL yl groups to the number of hydrogen atoms in methylene groups, as determined by nuclear magnetic resonance. For example, a simple hydrocarbon such as propane, which has six hydrocarbon groups in methyl groups and two hydrogen atoms in methylene groups will have a branchiness ratio of 6:2 or 3.0. In the complex hydrocarbons which make up the heavy alkylate bottoms oils treated according to this invention, a ratio of 3.0 requires two methyl groups for each methylene group, as in propane, but the ratio derives from a much more complicated structure involving highly branched naphthenic and isoparafiinic molecules. Preferably, the branchiness ratio is from about 3.0 to about 3.5.

As Table II illustrates, the naphthenic molecules of the heavy alkylate bottoms oils are predominantly polycyclic structures. These naphthenic molecules may be characterized according to a bicyclic ratio based on the number of monocyclic naphthenes and bicyclic naphthenes, as determined by mass spectrographic techniques. The bicyclic ratio of such naphthenic molecules is Within the range from about 0.4 to about 0.8, and preferably, within the range from about 0.45 to about 0.6.

The branchiness ratios and bicyclic ratios of several heavy alkylate bottoms oils are set forth in Table III. Ad-

Welght percent Silica gel analysis total Sample d1t1onal blCyCllC ratios are shown In Table VII.

saturates: TABLE III Isoparatfins 28. 7 Naphthenes 60. 9 HAB sample Total 89.6 1 2 3 4 Aromatics 3.8 B lling range 590-740 579-680 571-674 540-674 olars 1, 6 Branchiness ratio. 2. 95 3. 65 3.17 Blcyclic ratio 0.52 0.55 0.45 Grand total 100. 0

1 The manner in WhlCh the unique molecules 1n heavy ff am (136 alkylate bottoms oils influence the unusual viscosity char- ;gf acteristics of such oils is illustrated by Table IV below, 1 which summarizes data from thermal diffusions conducted 8-3; on a heavy alkylate bottoms oils having a N.B.P. range 1 at 10 volume percent of 622 F., at 50 volume percent 8-32 of 672 F. and at 90 volume/percent of 770 F. (As well known to the art, thermal diifusion separates an oil g-gg on the basis of viscosity index rather than on the basis of 60 molecular weight, on which fractional distillation separas -26 3 tion is grounded.) Analyses of the saturates fractions 5,3 5,133? 50pm us from each of the separations made by thermal diffusion igs are also included in Table IV. r g 3rlng-- 14. TABLE IV.THERMAL DIFFUSION ANALYSIS OF HEAVY gr m ALKYLATE BOTTOMS 01L r ng 6 ring 6 Fraction The aromatic fractions from silica gel separations contain between 1 2 3 4 5 30 to 50 weight percent oi naphthenic molecules with hydrogen characterization numbers less than 6. Thus, the actual aromatic concentrs- Volume percent of total 20 20 20 20 20 tions are probably between 4 to 6 weight percent. 7 $11 at F. SSU 1737 4%?) 8i? 2,

- 5 s -1 The saturated hydrocarbon molecules in heavy alkylate saturates fraction;

Isoparafiins 54 30 31 28 25 bottoms 0118 have many short h ghly branched slde chams Naphthenes 46 61 69 72 75 which are characterized by a high branchlness ratio of i from about 2.6 to about 3.9. The branchiness ratio rep- As the analysis of saturates fractions 1n Table IV inresent the ratio of the number of hydrogen atoms in meth- 75 dicates, the fractions having the lowest viscosity indexes are those having the highest concentrations of naphthene molecules.

The heavy alkylate bottoms oil which is hydrogen treated in accordance with the invention may be any fraction or combination of fractions thereof, including the total bottoms oil, boiling above the lower limit of 540 F. but below about 800 F., and having a viscosity within the range from about 75 SSU to about 3000 SSU at 100 F. and a viscosity index within the range from about to about -200. Preferably, the heavy alkylate bottoms oil has a nominal viscosity at 100 F. of 250 SSU or 500 SSU and a viscosity index within the range from about 50 to about 90. A heavy alkylate bottoms oil with a nominal viscosity at 100 F. of 250 SSU suitably may range in viscosity from about 200 SSU to about 300 SSU at 100 F., and will generally boil within the range from about 620 F. to about 680 F. with a 50% distillation point within the range from about 640 F. to about 660 F. A heavy alkylate bottoms oil with a nominal viscosity at 100 F. of 500 SSU suitably may range in viscosity from about 450 SSU to about 550 SSU at 100 F. and will generally boil within the range from about 640 F. to about 800 F with a 50% distillation point within the range from about 690 F. to about 720 F. The branchiness ratio of these preferred oils is within the range from about 2.6 to about 3.9. They have a bicyclic ratio of from about 0.4 to about 0.8.

In order to be used as a base oil in cosmetic oil formulations, it is highly desirable that a specialty oil have a low content of aromatic compounds. For example, USP Class A white oils, which are often used as cosmetic base oils, have a very low aromatics content, as evidenced by the fact that USP Class A white oil specifications require that the oil not have a DMSO extract UV absorbance exceeding 0.1 in any of the ranges of 260319 m 320- 329 m and 330-350 mg. Technical white oils, which are suitable for use in topical cosmetics, are required to have 21 DMSO extract UV absorbance of no more than 4.0 for the range of 280-289 mu, 3.3 for the range 290-299 mg, 2.3 for the range of 300-329 mg and 0.8 for the range 330-350 mg. The hydrogen treatment accorded the heavy alkylate bottoms oil in this invention provides the heavy alkylate bottoms oil with a low aromatic compounds content making it suitable for various cosmetic applications. Preferably, as a result of the hydrogen treatment, the oil produced has a DMSO extract UV absorbance no greater than that specified (above) for a technical white oil. Most preferably, the hydrogen-treated heavy alkylate bottoms oil has a DMSO extract UV absorbance within the ranges specified (above) for a USP Class A white oil.

Hydrogen refining the heavy alkylate bottoms oil The heavy alkylate bottoms oil is hydrogen refined in the presence of a sulfur-insensitive catalyst to reduce sulfur and nitrogen in the oil to levels which will permit the oil to be hydrogenated in the presence of a sulfur poisonable Group VIII metal hydrogenation catalyst to the extent that the oil meets the aforesaid criteria. Suitably, the hydrogen-refining conditions are adjusted to reduce sulfur levels to less than about 40 p.p.m., and preferably, to 20 p.p.m. or less of reducible sulfur compounds (expressed as sulfur). There are many sulfur-insensitive catalysts which may be used, typical sulfur-insensitive catalysts being cobalt molybdate, molybdenum disulfide, molybdenum oxides and the like. Ordinarily, cobalt molybdate on a suitable support such as alumina is preferred, in amounts of from about 1 to about 5 weight percent cobalt and from about 5 to about weight percent molybdenum both expressed as oxides, e.g. 3.7 weight percent cobalt oxide and 13.1 weight percent molybdate oxide. Suitable hydrofining conditions include a temperature within the range of from about 400 to about 700 F., preferably, within the range of from about 500 to about 600 F. and most advantageously, from about 500 to about 575 F. Below about 400 F., the temperature is insufficient to satisfactorily remove sulfur and improve color in the oil, and above about 700 F., severe cracking of the naphthenic molecules occur, resulting in viscosity reduction in the oil. Quality is progressively improved, and cracking is reduced or eliminated by operating at the more preferred temperatures.

A suitable hydrofining hydrogen pressure is from about 150 to about 2000 p.s.i.g., preferably within the range from about 500 to about 1000 p.s.i.g., and most preferably about 600 p.s.i.g. Below about 150 p.s.i.g., the pressure is insufficient to improve sulfur reduction and color improvement, and above about 2000 p.s.i.g., the pressure levels become uneconomical. A suitable hydrogen-treat rate occurs between about and about 1000 s.c.f./bbl., preferably, from about 450 to about 800 s.c.f./bbl., and most preferably at about 500-700 s.c.f./bbl. Below about 100 s.c.f./bbl., quality is insufiiciently improved in the product and above about 1000 s.c.f./bbl., no further improvement in product quality is noted. Hydrogen consumption ranges from about 2 to about 15 s.c.f./bbl.

A suitable liquid hourly space velocity for the hydrofining process occurs within the range from about 0.1 to about 10 volumes of oil per volume of catalyst per hour, preferably within the range from about 0.5 to about 3.0 v./v./hr., and most preferably, between about 2.0 and about 3.0 v./v./hr. Below about 0.1 v./v./hr., the liquid hourly space velocity is uneconomical, and above about 10 v./v./hr., the throughput is too rapid for sufficient improvement in sulfur reduction and for odor and color improvement.

Hydrogenation of the heavy alkylate bottoms oil The hydrogen-refined heavy alkylate bottoms oil is reacted with hydrogen in a hydrogenation zone in contact with a metal from Group VIII of the Periodic Table, e.g. nickel, platinum, paladium, or rhodium, preferably nickel. The hydrogenation catalyst is normally used either in granular or pellet form in a fixed bed. A typical supported nickel hydrogenation catalyst is nickel-kieselguhr. Suitable hydrogenation conditions include a temperature within the range of from about 400 to about 600 F., and most preferably about 500 F. Temperatures above about 650 F. produce severe cracking of the naphthenic molecules and reduce the vicosity of the oil produced. The lower viscosity oils within the 75 to about 3000 SSU at 100 F. range may be treated at the lower temperatures indicated.

A suitable hydrogenation pressure occurs within the range of from about 300 to about 3000 p.s.i.g., preferably from about 500 to about 1800 p.s.i.g. Below about 300* p.s.i.g., the pressure is insufiicient to effect satisfactory hydrogenation. Pressure levels greater than about 3000 p.s.i.g. are uneconomical. A suitable hydrogen-treat rate occurs within the range from about 300 to about 2500 s.c.f.bbl. of the oil, a preferred level being from about 800 to about 1000 s.c.f./bbl. Hydrogen consumption ranges from about 10 to about 35 s.c.f./bbl. A suitable liquid hourly space velocity occurs within the range from about 0.1 to about 3.0 volumes of oil per volume of catalyst per hour, preferably Within the range from about 0.20 to about 1.0 v./v./hr., and most preferably, between about 0.25 and 0.67 v./v./hr. Below about 0.10 v./v./hr., the process is uneconomical and above about 3.0 v./v./hr., the quality of the product is insufficiently improved in terms of reduced aromatics content and level of odor and color.

DESCRIPTION OF THE DRAWING The drawing is a schematic diagram of a preferred mode of carrying out the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawing, reference numeral 11 designates a charge line through which a heavy alkylate stream is introduced into a distillation zone 12, which suitably is a fractionation tower equipped with a heating element 13, suitably a steam coil or a furnace, for volatilizing the charge, and having baffle-type devices, suitably plates or other packing which bring liquid condensate into intimate counter-current contact with a rising vapor, as well known to the art. Heavy alkylate fractions boiling below about 540 F. are removed by overhead line 14. The heavy alkylate bottoms oils boiling above 540 F. are removed through line 15 and charged to a second distillation zone 16 constructed similarly to distillation zone 12. Distillation zone 16 is operated to recover a fraction of the heavy alkylate bottoms oil which will provide a desired viscosity. For example, to obtain a heavy alkylate bottoms oil having a nominal viscosity at 100 F. of 500 SSU, the heavy alkylate bottoms fraction boiling below, e.g., about 660 F. is taken overhead by line 17 for storage in the holding tank (not shown), and the portion of the heavy alkylate bottoms oil boiling, e.g., above about 780 F. is withdrawn by a bottoms line 18. The distillation cut of desired viscosity, in this case a nominal viscosity of 500 SSU at 100 F. and boiling over the range from about 660 F. to 780 F., is discharged from distillation zone 16 by line 19 and charged to a hydrogen-refining zone 20.

In hydrogen-refining zone 20, hydrogen is introduced through line 21 controlled by valve 22 to provide an amount of hydrogen within the range of from about 500 to about 600 s.c.f./bbl. of the distillation cut charged to the hydrogen-refining zone 20. The distillation cut from line 19 is passed across a sulfur-insensitive catalyst, preferably cobalt molybdate, at a liquid hourly space velocity of from about 0.5 to about 3.0 v./v./hr. under hydrogen pressures within the range of from about 500 to about 1000 p.s.i.g. and at temperatures within the range of from about 500 F. to about 600 F. For a 500 SSU distillation cut, suitable hydrogen-refining conditions include a temperature of 500-550 F., a LHSV of 2.0-3.0, a hydrogen pressure of 600 p.s.i.g., and a hydrogen-treat rate of 500 s.c.f./bbl. Hydrogen uptake is generally about 2-15 s.c.f./bbl.

As withdrawn from hydrogen-refining zone 20 by line 23, the hydrogen-refined heavy alkylate bottoms oil has a sulfur content of less than about 20 p.p.m., desirably less than about p.p.m., preferably about 1-3 p.p.m.,

The hydrogen-refined oil withdrawn by line 23 is introduced into hydrogenation zone 24, into which hydrogen is passed through a line 25 controlled by a valve 26 there to provide a hydrogen-treat rate within the range of from about 500 to about 1000 s.c.f./bbl. of the heavy gen pressure of 1500 p.s.i.g. and a hydrogen-treat rate of 800 s.c.f./bbl.

The hydrogenated oil withdrawn from hydrogenation zone 24 by line 27 has a boiling range Within the limits from about 540 F. to about 800 F., a viscosity within the range of from about 75 to about 3000 SSU at 100 F, a viscosity index within the range of from about 0 to about 200, a Saybolt color of no more than +25, and an aromatics compound content, as evidenced by UV absorption from a DMSO extract, comparable to that of white oils, most preferably of Class A white oils.

The invention is further illustrated in the following examples, which in their details are not intended to limit the scope of the invention.

EXAMPLES l-3 Examples 1-3 illustrate suitable hydrogen-refining and hydrogenation conditions for treating heavy alkylate bottoms oils formulated to have nominal viscosities at 100 F. of 150 SSU (Example 1), 500 SSU (Example 2), and 1200 SSU (Example 3). The three viscosity heavy alkylate bottoms oils were prepared by blending contiguous overhead fractions from the crude assay illustrated in Table V, using viscosity blending charts to estimate the upper and Transferred charge to 15 theoretical plate, 5:1 reflux ratio vacuum still.

Thus, the 9895 percent fraction was used for the 1200 vis oil; the 75-80 percent through 90-95 percent cuts inclusive were used to prepare the 500 vis oil; and the 65.5 percent and 65.5-75 percent fractions were used to prepare the 150 vis oil.

The blended 150, 500 and 1200 vis oils were then hydrogen refined and hydrogenated using the process condialkylate bottoms oil. In hydrogenation zone 24, the oil 1s 50 tions set forth in Table VI.

TABLE VI 500 Vis, 2nd pass 1,200 Vis 113 137 147 500 Vis, Product Vis Vis Vis 1st pass 450 500 1st pass 2nd pass 3rd pas Hydrogen-refining conditions-catalyst, Nalco 471 (CoMo):

Temperature, F 600 575 575 500 LHSV 1.0 1.0 2.0 2.0 Hz pressure, p.s.i.g. 600 600 600 I12 flow, s.e.f./bbl 500 500 500 Hydrogenation eonditionscatalyst NiT104: Temperature, F 400 400 400 425 450 500 430 450 500 LHSV 0. 67 0- 67 0- 67 0. 67 0. 67 0. 67 0. 67 0. 67 0. 67 H2 pressure, p.s.i.g 800 800 800 800 800 1, 500 800 800 1, 500 Hz flow, s.c.f./bl31 800 800 800 800 800 800 800 800 800 contacted with a Group VIII metal hydrogenation catalyst, preferably nickel on a kieselguhr support at a temperature within the range of from about 400 F. to about 600 F. under a hydrogen pressure within the range of from about 500 to about 2000 p.s.i.g. at a liquid hourly space velocity within the range of from about 0.20 to about 1.0 v./v./hr., resulting in a hydrogen uptake of less than about 10-35 s.c.f./bbl. Suitable hydrogenation conditions for a 500 SSU heavy alkylate bottoms oil are The hydrogenation catalyst was a Harshaw 104-T tabulated nickel catalyst which contains 58 percent nickel on kieselguhr with a ratio of reduced total nickel of 0.60- 0.65. The hydrogen-refining catalyst was Nalco 471, a cobalt molybdate catalyst on an alumina substrate in which 1 to 3 weight percent is cobalt, expressed as oxides and 5 to 10 Weight percent is molybdate, expressed as oxides. Post reactor stripping was used following hydrogen refining. The hydrogenated oils were not stripped. In the case a temperature of 500 F., a LHSV of 0.330.5, a hydroof the 150 vis oils, initial hydrogen-refining conditions caused excessive cracking, resulting in a 113 vis oil. Cracking was satisfactorily controlled for the 150 vis oil by reducing reactor temperature and increasing the liquid hourly space velocity, as indicated in Table VI. The conditions used to hydrogen refine the 500 vis oil and the 12 vis oil produce no cracking difficulties.

The hydrogen-refined oils from the 150 vis formulation temperature to recover a 90 volume percent o verhead fraction. This fraction was then hydrogenated over fresh Harshaw nickel T-l04 catalyst at 400 F., using an LHSV of 0.5 v./v./hr., a hydrogen-treat rate of 1000 s.c.f./bbl. and a hydrogen pressure of 800 p.s.i.g. The hydrogenated oil had the following inspection:

were hydrogenated at 400 F. and 0.67 liquid hourly space TABLE V111 velocity, producing Oils on one pass which were capable of I i Example 4 passing the DMSO extract UV absorption specification for 10 Sulfur, ppm. 13 Class A white oils of no more than 0.1 in the 260319, Nitrogen, p.p.m. 320-329 and 330-350 m ranges, as set forth in the Jou Color, Saybolt +30 nal of Association of Oflicial Agricultural Chemists, vol- Flash, F.(COC) 350 45, p. 66 (1962). However, with the 500 viscosity and 1200 Pour point, F. viscosity oils, it was necessary to use several passes of Viscosity, SSU: increasing hydrogenation severity to improve the color and 100 367 DMSO UV absorbance of those oils, as indicated in Tables 210 F. 46.2 VI and VII. Table VII details the inspections of the oils Viscosity index -64 produced under the conditions of Table VI. Specific gravity, 60 F. .8576

TABLE V1! 500 Vis, 2nd pass 1,200 Vis 113 137 147 500 Vis, Product Vis Vis Vis 1st pass 450 500 1st pass 2nd pass 3rd pass N B.P., F

10% 544 582 530 665 645 673 a 50%.-- 620 634 629 716 694 735 90%.--- 673 680 678 780 755 793 Viscosity,

100 F 113 137 147 425 464 444 1,139 1,115 1, 054 200 F 37. 6 39. 5 48.3 48. 9 48. 4 60. 7 60. 2 Viscosity index 52 68 -58 57 -55 -90 --83 Color, Saybolt--. +30 +30 +30 +26 +29 +15 +18 +25 Sulfur, p.p.m 1 1 1 1 1 1 9 1 1 Nitrogen, p.p.m 1 1 1 1. 7 1. 3 1 11 4 2 DMSO extract UV absorbance, m

260 27 .000 .000 .000 1.265 .373 .045 12.95 1.67 .148 000 000 .000 1. 263 373 .050 9. 400 1. 67 .148 .015 01 .005 1. 055 .305 .045 7. 500 1. 30 125 .03 .03 .019 .596 .194 .072 6.300 .820 .04 009 008 008 118 0.037 0.017 1. 125 155 .02 Pour point, F 30 15 -5 Aniline point, F 211 215 213 21s 219 a a Flash point (000), F 255 270 300 345 Bromine No 3. 2 1. 4 3. 7 7. 6 13.6 Clay gel analys saturates- 96.8 98. 5 98.1 96. 8 97. 5 98.1 94. 1 Aromatics 3. 2 1. 5 1. 9 3. 2 2. 5 1. 9 5.9 Polars. 0.0 0.0 0.0 0.0 0.0 0.0 0.0 saturates type: 6

Igopavafiins 56. 6 50. 6 57. 0 Naphthenes:

1 rin 12.1 16. 2 9. 8 ,155 19.5 21.6 19.8 3 rin 10. 2 9. 4 12. 3 4 rin 1. 0 2. 1 1. 0 5 rin 0. 7 0. 1 0. 1 6 ring 0. 0 0.0 0.0

Total 0.34 0.30 0.36 1. 24 0.70 0. 3.64 1.64 0.63

Bicyclic ratio. 0.62 0. 75 0.

1 Specifications for Class A white oil are 0.1 for the following my ranges: 260319; 320-329; 330-350. 3 Essentially identical to reported 500 vis values. 3 Essentially identical to reported 1,200 vis values. 4 Clay gel aromatics contain nonaromatie naphthenes. 5 Low resolution mass spectrometer. 6 Aromatics content relative. Values are not absolute concentrations. The 500 vis oil met UV absorption specifications for N.B.P. Range, F.: Class A white oils. The 1 200 vis oil met UV absorption 10% 585 specifications for technical white oils. Based on the re- 50% 673 sults of the inspections from the finished 1200 vis oil, 90% 770 the following hydrogenation conditions should produce Aniline Pt. F. 217 even better DMSO UV absorbance values and very good DMSO Absorbance, m color for heavy alkylate bottoms oils of such high vis- 280-289 0.104 cosities: a temperature of 500 F., a LHSV of 0.25-0.50, 290-299 0.080 a hydrogen pressure of 1500 p.s.i.g., and a hydrogen-treat 3004129 0.035 rate of 800 s.c.f./bbl. 330-350 0.007

EXAMPLE 4 This example illustrates the low toxological properties which a heavy alkylate bottoms oil hydrogen treated in accordance with this invention possesses.

A heavy alkylate bottoms oil boiling above about 585 F. was distilled in a vacuum column containing 15 theoretical plates with a 5:1'reflux ratio, maintaining constant boilup by reducing column pressure and/or increasing The hydrogenated oil was then tested for toxicity and dermal irritation. An acute oral LD 50 in rats was determined by administering graded doses of the oil to groups of albino rats.-The animals were observed for 14 days after dosing. For acute dermal LD 50 and dermal irritancy determinations, a group of albino rabbits was given a single application of undiluted hydrogenated oil at graded dosage levels. The application site was covered with an occlusive (impervious) binder for 24 hours, and

the animals were observed for 14 days. Acute eye irritation was also determined on rabbits using 0.1 ml. of the hydrogenated oil. All animals were observed for 7 days and the eyes were graded for irritancy. Repeated dermal toxicity and irritation studies were performed in rabbits. Undiluted material was applied to the skin of albino rabbits five days a week for two weeks at two dosage levels. Clinical studies and microscopic sight examination of selected tissues were also carried out. The results of these tests indicated that the hydrogenated oil has a very low oral toxicity with an LD 50 greater than 10 grams per kilogram. The oil could not be classified as either a skin or eye irritant.

From the foregoing, it will now be apparent that a colorless and odorless specialty oil having a viscosity within the range from about 75 SSU to about 3000 SSU at 100 F., a viscosity index within the range from about to about 200, and a very low aromatic compounds content, as evidenced by DMSC extract UV absorption data, may be prepared by hydrogen refining and then hydrogenating a heavy alkylate bottoms oil of approximately the same viscosity and viscosity index desired within such ranges and having a boiling range within the limits from about 540 F. to about 800 F., employing the hydrogenrefining and hydrogenating conditions described. The low DMSO extract UV absorptions and the low oral toxicities and failure of the hydrogen-treated heavy alkylate bottoms oil to act as a skin or eye irritant make the oil particularly suitable as a cosmetic oil. Thus, this invention provides a cosmetic oil having a viscosity at 100 F. greater than 500 SSU and up to about 3000 SSU. Moreover, within the viscosity at 100 F. ranges from 75 SSU to about 500 SSU, it provides a cosmetic oil having a viscosity index lower than any cosmetic oil heretofore known. In combination, the viscosity characteristics of this oil, as they range from 75 SSU to 3000 SSU at 100 F. with a correspondent viscosity index within the range from about 0 to about -200 provide an oil which, when warmed from room temperature to close to 100 F. by application to the body, becomes more fluid and has a greater cosmetic feel than any cosmetic oil heretofore known.

Having fully disclosed and particularly pointed out my invention, those skilled in the art will now be able to make various changes and modifications which nevertheless will fall within the spirit and scope of my invention as hereinafter claimed.

I claim:

1. A method of preparing a colorless and odorless oil useful as a cosmetic oil, comprising:

(a) reacting a heavy alkylate bottoms oil having a boiling range within the limits from about 540 F. to about 800 F., a viscosity within the range of from about 75 SSU to about 3000 SSU at 100 F., and a viscosity index within the range from about 0 to about 200 with hydrogen in a hydrogen-refining zone in the presence of a sulfur-insensitive catalyst under hydrogen-refimng conditions including:

.a temperature within the range from about 400 to about a hydrogen pressure within the range from about 150 to about 2000 p.s.i.g.,

a liquid hourly space velocity within the range from about 0.1 to about 3.0 v./v./hr., and

a hydrogen-treat rate within the range from about 100 to about 1000 s.c.f./bbl. of said heavy /alkylate bottoms oil, and

(b) reacting the hydrogen-refined heavy alkylate bottoms oil with hydrogen in the presence of a Group VIII metal hydrogenation catalyst under hydrogenation conditions which include:

a temperature within the range from about 300 F. to about 650 F.,

a hydrogen pressure within the range from about 300 to about 3000 p.s.i.g.,

a liquid hourly space velocity within the range of from about 0.1 to about 3.0 v./v./hr., and

a hydrogen-treat rate within the range from about 300 to about 2500 s.c.f./bbl. of said hydrogenrefined heavy alkylate bottoms oil.

2. The method of claim 1 in which said heavy alkylate bottoms oil has a branchiness ratio within the range from about 2.6 to about 3.9.

3. The method of claim 1 in which said heavy alkylate oil has a bicyclic ratio of from about 0.4 to about 0.8.

4. The method of claim 1 in which said heavy alkylate bottoms oil has a viscosity within the range from about SSU to about 1500 SSU at 100 F. and wherein said hydrogen-refining conditions include:

(a) a temperature within the range from about 500 F.

to about 600 F.,

(b) a liquid hourly space velocity within the range from about 0.5 to about 3.0 v./v./hr.,

(c) a hydrogen pressure within the range from about 500 to about 1000 p.s.i.g., and (d) a hydrogen-treat rate within the range from about 450 to about 800 s.c.f./bbl. 5. The method of claim 4 in which said sulfur-insensitive catalyst is cobalt molybdate.

6. The method of claim 1 in which said hydrogenrefined heavy alkylate bottoms oil has a viscosity within the range from about 100 SSU to about 1500 SSU at 100 F. and wherein said hydrogenation conditions include:

(a) a temperature within the range from about 400 F. to about 600 F.,

(b) a liquid hourly space velocity within the range from about 0.2 to about 1.0',

(c) a hydrogen pressure within the range from about 500 to about 2000 p.s.i.g., and

(d) a hydrogen-treat rate within the range from about 500 to about 1000 s.c.f./bbl.

7. The method of claim 6 in which Group VIII metal hydrogenation catalyst is a nickel catalyst.

8. The method of claim 1 wherein said heavy alkylate bottoms oil has a boiling range within the limits from about 640 F. to about 800 F. with a 50% distillation point within the range from about 690 F. to about 720 F., and has a viscosity within the range from about 450 SSU to about 550 SSU at 100 F. and a viscosity index within the range from about 50 to about -90.

9. The method of claim 8 in which said hydrogen refining conditions include:

(a) a temperature within the range from about 500 F. to about 600 F.,

(b) a liquid hourly space velocity within the range from about 0.5 to about 3.0 v./v./h.r., (c) a hydrogen pressure within the range from about 500 to about 1000 p.s.i.g., and

(d) a hydrogen treat rate within the range from about 450 to about 800 s.c.f./bbl.,

and wherein said hydrogenation conditions include:

(a) a temperature within the range from about 400 F. to about 600 F.,

(b) a liquid hourly space velocity within the range from about 0.2 to about 1.0,

(d) a hydrogen treat rate within the range from about 500 to about 1000 s.c.f./bbl.

10. The method of claim 1 wherein said heavy alkylate bottoms oil has a boiling range within the limits from about 620 F. to about 680 F. with a 50% distillation point within the range from about 640 F. to about 660 F., said oil having a viscosity within the range from about 200 SSU to about 300 SSU at 100 F., and a viscosity index within the range from about 50 to about 90.

11. The method of claim wherein said hydrogen refining conditions include:

(a) a temperature within the range from about 500 F to about 600 F.,

(b) a liquid hourly space velocity within the range from about 0.5 to about 3.0 v./v./hr., (c) a hydrogen pressure Within the range from about 500 to about 1000 p.s.i.g., and

and wherein said hydrogenation conditions include:

(a) a temperature within the range from about 400 F to about 600 'F.,

(d) a hydrogen treat rate within the range from about 500 to about 1000 s.c.f./bbl. 12. A colorless and odorless heavy alkylate oil boiling Within the range from about 640 F. to about 800 F. with a 50% distillation point within the range from about 690 F. to about 720 F., and further having:

a viscosity within the range from about 450 SSU to about 550 SSU at 100 F.,

a viscosity index within the range from about 50 to about 90,

a branchiness ratio within the range from about 2.6

to about 3.9,

a bicyclic ratio of from about 0.4 to about 0.8,

a Saybolt color of at least +25, and

a DMSO extract UV absorbance of no more than about 4.0 for 280-289 mg, 3.3 for 290-299 mg, 2.3 for 300-329 m and 0.8 for 330-350 mg.

13. The oil of claim 12 having an LD 50 oral toxicity of greater than 10 grams per kilogram of body weight.

14. The oil of claim 12 having a DMSO extract UV 14 absorbance of no more than 0.1 in any of the millimicron ranges of 260-319, 320-329 and 330-350.

15. A colorless and odorless heavy alkylate oil boiling within the limits from about 620 F. to about 680 F. and having a distillation point within the range from 640 F. to 660 F., and further having:

a viscosity within the range from about 150 SSU to about 250 SSU at F.,

a viscosity index within the range from about -50 to about 90,

a branchiness ratio within the range from about 2.6

to about 3.9,

a bicyclic ratio within the range from about 0.4 to

about 0.8,

a Saybolt color of at least +25, and

a DMSO extract UV absorbance of no more than 4.0

for 280-289 m 3.3 for 29-299 m 2.3 for 300- 329 I'll 1., and 0.8 for 330-350 mg.

16. The oil of claim 15 having an LD 50 oral toxicity of greater than 10 grams per kilogram of body weight.

17. The oil of claim 15 having a DMSO extract UV absorbance of no more than 0.1 in any of the millimicron range of 260-319, 320-329, and 330-350.

References Cited UNITED STATES PATENTS 2,915,452 12/1959 Fear 208-144 3,121,678 2/1964 Behyzner et a1. 208212 3,328,293 6/1967 Brenken 208-143 3,459,656 8/1969 Rausch 208-144 HERBERT LEVINE, Primary Examiner US. Cl. X.R. 208-49, 89, 144