FI96775B - Lubricant composition and method of making it - Google Patents

Description

- 96775

This invention relates to novel lubricant compositions consisting of 030 ^ 1300 to ^ ^ ^ ^ ^ 8 ^, and more particularly to novel synthetic lubricant compositions prepared from alpha-olefins having from 6 to 20 carbon atoms and mixtures thereof. In particular, the invention relates to novel synthetic lubricant compositions made from 1-alkenes having excellent viscosity indices and other improved properties that are essential for useful lubricating oils. This invention further relates to a process for preparing such lubricant compositions.

15 Efforts to improve the performance of natural mineral oil-based lubricants in the synthesis of oligomeric hydrocarbon fluids have been the subject of important research and development in the oil industry for at least fifty years and have relatively recently led to a large number of oligomerization of olefins or 1-alkenes. With regard to improving the lubricity property, the focus of the industrial research input on synthetic lubricants has been in liquids with useful viscosities over a wide temperature range, i.e. improved viscosity index (VI), while their lubricity, thermal and oxidative stability and solidification point are equally good. or better than mineral oil. These new synthetic lubricants reduce friction and thus improve mechanical efficiency across the full range of mechanical loads from worm gear to traction, thus making a wider range of 2,96775 operating conditions than mineral oil lubricants.

The chemical 5 focal point of the research input for synthetic lubricants has been in the polymerization of 1-alkenes. The well-known structure / property dependences of high polymers in the various branches of polymer chemistry have shown the way for 1-alkenes to be a fertile area for the synthesis of oligomers, 10 that structure is needed to give them improved lubricating properties. Due in large part to studies of the polymerization of propylene and vinyl monomers, the mechanism of polymerization of 1-alkenes and the effect of this mechanism on the structure of the polymer are reasonably well controlled, requiring the allocation of strong resources to potentially useful oliomerization methods and oiomerizations. Based on these resources, oligomers of C 1 -C 10 alkenes have been previously prepared in the art, with commercially useful synthetic lubricants from the oligomerization of 1-decene clearly producing an excellent lubricant product with either a cationic or Zieqler-catalyzed oligomer.

Theoretically, the olomerization of 1-decene to, for example, a C30-C40 lubricant oligomer in the range of 25 can result in a very large number of structural isomers. Henze and Blair, J.A.C.S.

54, 1538 have calculated more than 60x1012 isomers for the Cs o-C, i o region. The precise invention of these isomers and the associated oligomerization process, which produces an inexpensive and excellent synthetic lubricant that meets the specification requirements for a wide range of temperatures while maintaining a low pour point, represents a tremendous challenge for those skilled in the art.

Brennan, Ind. ENQ. Chem. Prod. Res. Dev. 1980, 19, 2-6 35 mentions a 1-decene trimer as an example of the structure.

li 3 to 96775 which is compatible with structures associated with excellent low temperature fluidity in which the concentration of atoms is very close to the center of the chain of carbon atoms.

It also describes the apparent dependence of the properties of the oligomer on the oligomerization process, i.e. the cationic or Zieqler-type catalyst polymerization, which are known and practiced in the art.

One property of the molecular structure of 1-alkene oligomers that has been found to correlate very well with improved lubricating properties in commercial synthetic lubricants is the ratio of methyl to methylene groups in the oligomer. The ratio is called the branching ratio and is calculated from the results of the infrared spectrum as described in "Standard Hydrocarbons of High Molecular Weight", Analytical Chemistry, Part 25, No. 10, page 1466 (1953). The viscosity index has been found to increase with decreasing branching ratio. To date, oligomeric lubricants with very low branching ratios have not been synthesized from 1-alkenes. For example, oligomers prepared from 1-decene by either cationic polymerization or Ziegler catalyst polymerization have branching ratios greater than 0.20. Shubkin, Ind. Eng. Chem. Prod. Res. Dev. 1980, 19, 25 1519, provides an explanation for the seemingly limited value of the branching ratio based on a cationic polymerization reaction mechanism involving branching-causing rearrangement of atoms. Other disclosures suggest isomerization of the olefinic group at position one to produce the internal olefin as the cause of branching. Whether branching occurs by rearrangement of atoms, isomerization, or an as yet unconfirmed mechanism, it is clear that in the oligomerization technique of 1-alkenes for the production of synthetic lubricants currently practiced, excessive branching occurs and limits the achievable 4,96775 lubricant properties. It will be appreciated that increased branching will increase the number of isomers in the oligomer mixture, diverting the composition away from a structure that would be advantageous from the theoretical ideas described above.

The U.S. U.S. Patent 4,282,392 to Cupples et al. discloses a synthetic alpha-olefin oligomer ointment having an improved viscosity-volatility ratio of 10 and containing a large amount of tetramer and pentamer due to a hydrogenation process that results in rearrangement and isomeric rearrangement of the molecular backbone. In the composition shown, the ratio of trimer to tetramer is at most 1: 1. The branching relationship is not disclosed.

15

A process for the use of coordination catalysts in the preparation of high polymers from 1-alkenes, especially with the support of a chromium catalyst on silica, has been described by Weiss et al. Jour. Catalysis 88, 424-430 (1984) and Offen. DE 3 427 319.

The process and products obtained therefrom are described in more detail below in comparison to the process and products of the present invention.

It is well known that Lewis acids such as accelerated BF 3 and / or metal halides can catalyze Friedel-Crafts type reactions. However, olefin oligomers, and more particularly PAO oligomers, have been prepared by methods in which isomerization of the starting 1-olefin double bond occurs readily. As a result, the olefin oligomers 30 have more short side branches. These side branches ruin their lubricating properties.

Oligomerization of Ce-C20-1-alkenes has yielded liquid hydrocarbon lubricant compositions having a surprisingly high viscosity index (VI), while surprisingly having very low solidification points. The compositions contain a C30-C100 hydrocarbon and have a branching ratio of 0.1 to 0.16; a weight average molecular weight of 300 to 45,000; a number average molecular weight of 300 to 18,000; a molecular weight distribution of 1 to 5 and a pour point below -15 ° C.

Further, a composition has been invented comprising 11-octyldidosan having structure 10

B

CH3 (CH2) 10C (CH2) 9CH3 15 (CH2) 7 ch3

The above composition has been found to have excellent lubricating properties either alone or in admixture with 9-methyl, 11-octylhenecosan. Surprisingly, the mixture has a viscosity index above 130, preferably 130-280 while maintaining its pour point below -15 ° C. These compositions represent the present invention including C3QHg2 alkanes having a branching ratio or CH3 / CH2 ratio of 0.10 to 0.16. These low branching ratios and pour points are characteristic of the compositions of this invention, referred to herein as polyalphaolefin or HVI-PAO, which give the compositions particularly high viscosity indices compared to commercially available synthetic polyalphaolefin (PAO) lubricants.

The unique lubricant oligomers of this invention can also be prepared over a wide range of molecular weights and viscosities, including C30-C100-iives, with a branching ratio of between 0.1 and 0.16 and a molecular weight distribution of about 1.05. -2.5. These oligomers can be blended with conventional mineral oils or fats that have other properties of their own properties to provide compositions that also have excellent lubricating properties.

The compositions of this invention can be prepared by oligomerizing 5-alpha-olefins, such as 1-decene, under contact with an oligomerization conditions supported and reduced in valence state to a metal oxide of Group VIB of the IUPAC Periodic Table. Chromium oxide is the preferred metal oxide.

This invention relates to a process for the preparation of liquid oligomers from olefins, such as 1-decene, having oligomer branching ratios ranging from 0.1 to 0.16 and having higher viscosity indices than oligomers having higher branching ratios. These low branching ratio oligomers can be used as basic feedstocks for many lubricants or greases with improved viscosity-temperature ratio, oxidation stability, volatility, etc. They can also be used to improve the viscosities and viscosity indices of lower quality oils. For example, olefins can be oligomerized over a Group VIB metal oxide catalyst in a supported and reduced Periodic Table to provide oligomers suitable for lubrication applications. More specifically, this patent application is directed to a process for oligomerizing olefinic hydrocarbons having from 6 to 20 carbon atoms, wherein said hydrocarbon is oligomerized under oligomerization conditions, wherein the reaction product consists essentially of non-isomeric olefins and, for example, alpha-olefins are not isomerized, for example in the presence of a suitable catalyst, for example a supported and reduced Group VIB metal oxide catalyst 35.

7 96775

The use of a reduced Group VIB chromium-containing metal oxide with an inert support to oligomerize liquid olefins, "which are suitable for use as good quality lubricating oils, is a new technique.

Figure 1 is a comparison of PAO and HVI-PAO syntheses.

Figure 2 compares the VI values of PAO and HVI-PAO.

10

Figure 3 shows the solidification points of PAO and HVI-PAO.

Figure 4 shows the C-13 NMR spectrum of HVI-PAO prepared from 4-hexene.

15

Figure 5 shows the C-13 NMR spectrum of 5 mm 2 / s HVI-PAO prepared from 1-decene.

Figure 6 shows the C-13 NMR spectrum of 50 mm2 / s HVI-20 PAO prepared from 1-decene.

Figure 7 shows the C-13 NMR spectrum of 145 mm 2 / s HVI-PAO prepared from 1-decene.

Figure 8 shows the gas chromatogram of the 1-decene HVI-PAO trimer.

Figure 9 shows the C-13 NMR spectrum of the 1-decene HVI-PAO trimer.

Figure 10 shows the chemical shifts calculated / observed from the C-13 NMR spectrum of the HVI-PAO trimer components of 1-decene.

35 8 96775

Unless otherwise indicated, in the following description, all references to HVI-PAO oligomers or lubricants refer to hydrogenated oligomers and lubricants while adhering to a practice well known to those skilled in the art of lubricant production. When oligomerized, HVI-PAO oligomers are mixtures of dialkylvinylidene and 1,2-dialkyl or trialkyl monoolefins. Lower molecular weight unsaturated oligomers are preferably hydrogenated to produce thermally and oxidatively stable, useful lubricants. Higher molecular weight unsaturated HVI-PAO oligomers are thermally stable enough to be used without hydrogenation and can optionally be used in that manner. Both unsaturated and hydrogenated HVI-PAO oligomers of lower or higher molecular weight have viscosity indices of at least 130, preferably 130-280, and pour points below -15 ° C, preferably -45 ° C.

Referring to Figure 1, the novel oligomers or high viscosity index polyalphaolefins (HVI-PAO) of the present invention are described in a comparison comparing them with conventional polyalphaolefins (PAOs) prepared from 1-decene. Polymerization with the new reduced chromium catalyst described below results in an oligomer that is substantially free of isomerization of the double bond. On the other hand, conventional PAO accelerated with BF3 or AlCl3 forms a carbonium ion, which in turn promotes the isomerization of the olefinic bond and the formation of several isomers. The HVI-PAO prepared in the present invention has a structure in which the CH 3 / CH 2 ratio is between 0.1 and 0.16 when the PAO is> 0.20. 30: Figure 2 compares the relationship between viscosity index and viscosity with HVI-PAO and PAO lubricants, showing that HVI-PAO is clearly better than PAO at all viscosities tested. It should be noted that despite the more regular structure of HVI-PAO oligomers, as indicated by the branching ratio, which leads to an improved viscosity index (VI), they have better solidification points than PAO. It is conceivable that oligomers with a regular structure containing fewer isomers would be expected to have higher solidification temperatures and higher pour points, which would reduce their utility as lubricants. Surprisingly, however, this is not the case with the HVI-PAO of the present invention. Figures 2 and 3 illustrate the superiority of HVI-PAO in terms of both solidification point and VI value.

It has been found that the process described herein for preparing the novel HVI-PAO-15 oligomers can be adjusted to produce oligomers having a weight average molecular weight of between 300-45,000 and a number average molecular weight of between 300-18,000. Measured as the number of carbon atoms, the molecular weights range from C3 to C100 and viscosities up to 750 to 20 mm 2 / s at 100 ° C, with a preferred molecular weight range of C 30 ° C / 000 and a viscosity of up to 500 mm 2 / s at 100 ° C and preferably between 3 and 750 mm 2 / s. Molecular weight distributions (MWD), defined as the ratio of weight average molecular weight to number average molecular weight, range from 1.00 to 5, with a preferred range of 1.01 to 3 and an even more preferred MWD of about 1.05 to 2.5. Compared to conventional PAO from BF 3 or AlCl 3 catalyzed polymerization of 1-alkene, the HVI-PAO of this invention has been found to have a higher proportion of high molecular weight polymer molecules in the product.

The viscosities of the new HVI-PAO oligomers, measured at 100 ° C, range from 3-5000 mm 2 / s. The viscosity index of the new polyalpha-olefins is approximated by the following 35 equations: 10 96775 VI = 129.8 + 4.58 x (Flow oc) ° · 5, where Vioooc is the kinematic viscosity in mm2 / s measured at 100 ° C.

The novel oligomer compositions disclosed herein have been studied to determine their unique structure in addition to the important branching ratio and molecular weight properties already mentioned. The dimer and trimer fractions have been separated by distillation and their components have been further separated by gas chromatography. These lower oligomers and components, together with complete reaction mixtures of HVI-PAO oligomers, have been studied using infrared spectroscopy and C-13 NMR analysis. Studies have confirmed the highly uniform structural composition of the products of this invention, especially compared to conventional polyalpha-ole-15 fins prepared by BFs, AlCl 3 or Ziegler type catalysis. The unique ability of C-13 NMR analysis to identify structural isomers has led to the identification of distinct compounds in the lower oligomer fractions and has acted to confirm a higher molecular weight isomeric mixture in 20 oiomomers, consistent with low branching ratios and excellent viscosity indices.

The HVI-PAO oligomers derived from 1-hexene of this invention have been shown to have a highly homogeneous linear C4 branch and to contain regular head / tail linkages. In addition to the structures obtained from regular head / tail junctions, the main body structures have some head / main junctions, indicating the following structure confirmed by NMR analysis: H (-CH-CH 2 -) x - (-CH 2 -CH-) V H (CH 3. The NMR spectrum of (CH2) 3 CH3 CH3 35 Poly (1-hexene) is shown in Figure 4.

I! 96775 11 Oligomerization of 1-decene with reduced valence supported chromium also produces HVI-PAO. The structure of the hip is analogous to the structure of the 1-hexene oligomer. After distillation and hydrogenation to remove light liquors, the lubricant products 1a have a characteristic C-13 NMR spectrum. Figures 5, 6 and 7 are the C-13 NMR spectra of typical HVI-PAO lubrication products with viscosities of 5.50 and 145 mm 2 / s at 100 ° C.

10

In the following tables, Table A represents the NMR results of Figure 5, Table B represents the NMR results of Figure 6, and Table C represents the NMR results of Figure 7.

12 96775

Table A (Figure 5)

Item Offset (ppm) Intensity Width (Hz) 1,79,096 138841 2,74 5 2 74,855 130653 4,52 3 42,394 148620 6,68 4 40,639 133441 37,6 5 40,298 163678 32,4 6 40,054 176339 31,2 10 7 39,420 134904 37,4 8 37,714 445452 7,38 9 37,373 227254 157 10 37,081 145467 186 11 36,788 153096 184 15 12 36,593 145681 186 13 36,447 132292 189 14 36,057 152778 184 15 35,619 206141 184 16 35,082 505413 26,8 20 17 34,351 74 , 3 18 34,059 1265077 7,65 19 32,207 5351568 1,48 20 30,403 3563751 4,34 21 29,965 8294773 2,56 25 22 39,623 4714955 3,67 23 28,356 369728 10,4 24 28,161 305878 13,2 25 26,991 1481260 4, 88 26 22,897 4548162 1,76 30 27 20,265 227694 1,99 28 14,221 4592991 1,62 ti 96775 13

Table B (Figure 6) No. Frequency (Hz) ppm Intensity,% 1 1198.98 79.147 1856 5 2 1157.95 77.004 1040 3 1126.46 74.910 1025 4,559.57 37.211 491 5 526.61 35.019 805 6 514 , 89 34,240 1298 10 7 509,76 33,899 1140 8 491,45 32,681 897 9 482,66 32,097 9279 10 456,29 30,344 4972 11 488,24 29,808 9711 15 12 444,58 29,564 7463 13 426,26 28,347 1025 14 401 , 36 25,691 1690 15 342.77 22.794 9782 16 212.40 14.124 8634 20 17 0.00 0.000 315 14 96775

Table C (Figure 7)

Item Offset (ppm) Intensity Width (Hz) 1,76.903 627426 2.92 5 2 40,811 901505 22.8 3 40,568 865686 23.1 4 40,324 823178 19.5 5 37,158 677621 183 6 36,915 705894 181 10 7 36,720 669037 183 8 36,428 691870 183 9 36,233 696323 181 10 35,259 1315574 155 11 35,015 1471226 152 15 12 34,333 1901096 121 13 32,726 1990364 120 14 32,141 20319110 2,81 15 31,362 1661594 148 16 30,388 9516199 19,6 20 17 29,901 17778892 9,64 , 17 19 28,391 1869681 122 20 27,514 1117864 173 21 26,735 2954012 14.0 25 22 22,839 20895526 2.17 23 14,169 16670130 2.06

In general, the novel oligomers have the following regular head / tail structure, where n may be 3-17:30 - (CH 2 -CH) n - (CH 2) n CH 5 which may have some head / end joints.

The trimer of the 1-decene HVI-PAO oligomer is separated from the oligomerization mixture by distillation from freshly synthesized HVI-PAO having a viscosity of 20 mm 2 / s in a short path apparatus at 165-210 ° C at 13.3-26.6 Pam. The non-hydrogenated trimer had the following viscosimetric properties: V at 40 ° C = 14.88 mm 2 / s; V at 100 ° C: 3.67 mm 2 / s; VI = 137.

The trimer is hydrogenated at 235 ° C and 4 H ka H 2 with a diatomaceous earth-supported Ni hydrogenation catalyst 11 to give a hydrogenated HVI-PAO trimer having the following properties: V at 40 ° C = 16.66 mm 2 / s; V at 100 ° C = 3.91 mm 2 / s; VI = 133; freezing point below -45 ° C.

15

Gas chromatographic analysis of the trimer reveals that it consists essentially of two components with retention times of 1810 s and 1878 s under the following conditions: 20 Gas chromatographic column (qc) - 60 m narrow column, inner diameter 0.32 mm, coated with SP With a well thickness of 25 mm, available from a chromatograph supply company called Supel-co, catalog no. 2-4046.

25

Separation conditions - Varian gas chromatograph model 3700, equipped with a flame ionizer detector11a and a capillary-syringe orifice1a with a gap ratio of about 50. The flow rate of the N? Carrier gas is 2.5 ml / min. Inlet temperature 300 ° C; 30 detection orifice temperature 330 ° C, column temperature initially set at 45 ° C for 6 minutes, programmed heating rate. 15 ° C / min to a final temperature of 300 ° C and a holding time of 1 minute at a final temperature of 60 minutes. The sample injection size is 1 μl. Under these conditions, the retention time of the gas chromatographic standard, n-dodecane 35, is 968 s.

16 96775

A typical chromatogram is shown in Figure 8.

The C-13 NMR spectrum of the distilled C30 product (Figure 9) confirms the chemical structures. Table D lists the C-13 NMR data of Figure 9.

ii 96775 17

Table D (Figure 9)

Item Offset (ppm) Intensity Width (Hz) 1 55,987 11080 2,30 5 2 42,632 13367 140 3 42,388 16612 263 4 37,807 40273 5,90 5 37,319 12257 16,2 6 36,539 11374 12,1 10 7 35,418 11631 35,3 8 35,126 33099 3,14 9 34,638 39277 14,6 10 34,054 110899 3,32 11 33,615 12544 34,9 15 12 33,469 13698 34,2 13 32,981 11278 5,69 14 32,835 13785 57,4 15 32,201 256181 1,41 16 31,811 17867 24,6 20 17 31,470 13327 57,4 18 30,398 261859 3,36 19 29,959 543993 1,89 20 29,618 317314 1,19 21 28,838 11325 15,1 25 22 28,351 24926 12,4 23 28,156 29663 6,17 24 27.230 44024 11.7 25 26.986 125437 -0.261 26 22.892 271278 1.15 30 27 20.260 17578 -22.1 28 14.167 201979 2.01 18 96775 The locations of the individual peaks in the C-13 spectrum are shown in Figure 9. Based on these structures, the values shown in Figure 10 are shown in Figure 10. the calculated chemical shifts correspond exactly 5 to the observed chemical shifts. Calculation of hydrocarbon chemical shifts is performed as described in "Carbon-13 NMR for Organic Chemists", G.C. Levy and G.L. Nelson, 1972, John Wiley & Sons, Inc., Chapter 3, pages 38-41. The components were identified as 9-methyl, 10-11-octylhenecosan and 11-octyldocosan by infrared and C-13 NMR analyzes, and heneicosan and docosan were found to be present in ratios between 1:10 and 10: 1. The refractive index of the hydrogenated 1-decene trimer prepared by the process of this invention at 60 ° C is 1.4396.

The process of this invention surprisingly produces a simpler and more useful dimer than a dimer prepared by oligomerization of 1-alkene with BF 3 or AlCl 3, which is commercially practiced. In the present invention, it has typically been found that a significant portion of the non-hydrogenated dimerized 1-alkene has the following vinylidenyl structure: CH? = CRiRj where Ri and R? are alkyl groups representing a residue of a 1-alkene molecule from a head / tail addition. For example, the 1-decene dimer of this invention has been found to contain only three major components as determined by gas chromatography. Based on C13 NMR abalysis, the non-hydrogenated components were found to be 8-eicosene, 9-eicosene, 2-octyldodecene and 9-methyl-8- or 9-methyl-9-nonadecene. The hydrogenated dimer components were found to be n-eicosan and 9-methylnonacosane.

Suitable olefins for use as starting materials in this invention include olefins having from about 2 to about 20 carbon atoms, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, li 96775 19 l-octene, 1-decene, 1-dodecene and 1-tetradecene and branched chain isomers such as 4-methyl-1-pentene. Also suitable for use are olefin-containing oil refinery feedstocks and effluents. However, the olefins used in this invention are preferably alpha-olefinic, such as, for example, 1-heptene ... 1-hexadecene and more preferably 1-octene ... 1-tetradecene or mixtures of these olefins.

According to the present invention, oligomers of alpha-olefins have a low branching ratio of less than 0.19 and better lubricating properties than alpha-olefin oligomers having a high branching ratio and produced by all known commercial methods.

15 This new class of alpha-olefin oligomers is prepared by oligomerization reactions in which the majority of the double bonds of alpha-olefins are not isomerized. These reactions include oligomerization of alpha-olefins with supported metal oxy-dicatalysts, such as Cr compounds on silica or other supported compounds of Group VIB of the IUPAC Periodic Table. The most preferred catalyst is a lower valence Group VIB metal oxide with an inert support. Preferred supports are silicon dioxide, alumina, titanium dioxide, silica-alumina, magnesium oxide, etc. The support material binds the metal oxide catalyst. Porous substrates with a pore opening of at least 40 x 10′4 μιη are preferred.

30

The support material usually has a large surface area and large pore volumes with a mean pore size of 40-350 x 10'4 μιη. A large surface area is advantageous for supporting a large number of highly dispersible, active chromium metal centers and for obtaining the maximum efficiency of metal utilization, resulting in a very high activity catalyst. The support 96775 should have large central pore openings of at least 40 x 10'4, with a preferred central pore opening of> 60-300x 10'4. This large pore orifice does not cause any reagent and product diffusion limitations to and from the active catalytic metal centers, further optimizing catalyst productivity. Likewise, for the use of this catalyst in a fixed bed or slurry reactor and for its recirculation and regeneration several times, a silica support having good physical strength is preferred to prevent abrasion or degradation of the catalyst particle during the treatment or reaction.

Supported metal oxide catalysts are preferably prepared by impregnating the support metal salt 11a dissolved in water 15 or organic solvents. Any organic solvent known in the art, for example ethanol, methanol or acetic acid, can be used. The solid catalyst precursor is dried and then calcined at 200-900 ° C with air or other oxygen-containing gas. The catalyst is then reduced with any of a variety of well-known reducing agents, such as CO, H 2, NH 3, H 2 S, CS 2, CH 3 SCH 3, CH 3 SSCH 3, metal alkyl-containing compounds such as R 3 Al, R 3 B, R 2 Mq, RLi, R 5Zn wherein R is an alkyl, alkoxy, aryl group, etc. Preferred are CO or H? or compounds containing metal alkyl.

Alternatively, the Group VIB metal may be applied to the substrate in a reduced form, such as CrII compounds. The resulting catalyst is very active in the oligomerization of olefins in the temperature range from below room temperature to about 250 ° C, preferably at 90-250 ° C, most preferably at 100-180 ° C in the pressure range 10.1- 34500 kPa. The contact time of both the olefin and the catalyst can range from one second to 35 hours. The weight flow rate per hour (WHSV) is 0.1-

II

21 96775 10 based on the total weight of the catalyst. The catalyst can be used in a batch type reactor or in a solid bed continuous flow reactor.

In general, the support material can be added to a solution of metal compounds, e.g., acetates or nitrates, etc., and the mixture is stirred and then dried at room temperature. The dry solid gel is continuously purified at higher temperatures up to 600 ° C for 16-20 hours.

The catalyst is then cooled in an inert atmosphere to a temperature of 250-450 ° C and a stream of pure reducing agent is contacted with it for sufficient CO to have passed through to reduce the catalyst, as evidenced by a clear color change from bright Orange-15 to pink. Typically, the catalyst is treated with an amount of CO corresponding to twice the stoichiometric excess to reduce the catalyst to a lower valence CrII state. Finally, the catalyst is cooled to room temperature and ready for use.

20

Product oligomers have a very wide range of viscosities and high viscosity indices suitable for high performance lubrication applications. The product oligomers also have an atactic molecular structure with mostly one-to-25 independent head-to-tail joints and only some head-to-end type joints. These low branching ratio oligomers have high viscosity indices of at least 15-20 units and typically 30-40 units higher than prior art oligomers of similar viscosity with regularly higher branching ratios and correspondingly lower viscosity indices. These low branching ratio oligomers retain better or comparable pour points.

The branching ratios, defined as the ratios between the CH3 groups and the CH2 groups in the lubricating oil, are calculated from the weight fractions of the methyl groups obtained by infrared methods published in Analytical Chemistry, Part 25, No. 10, page 1466 (1953).

Branching ratio = methyl group weight fraction 5 l- (methyl group weight fraction)

As mentioned above, the supported Cr metal oxide in the various oxidation states is known to polymerize C3-C2cralfa_ ° le · fines (DE 3 427 319, issued as HL Krauss and 10 Journal of Catalysis 88, 424-430, 1984) using a catalyst prepared from a silica-supported -C ^ zsta. Said disclosures teach that the polymerization takes place at low temperatures, usually below 100 ° C, to give adhesive polymers, and that at high temperatures the catalyst promotes isomerization, cracking and hydrogen transfer reactions. This invention produces low molecular weight oligomer products under reaction conditions and using catalysts that minimize side reactions such as 1-olefin isomerization, cracking, hydrogen transfer, and aromatization. To prepare new low molecular weight products suitable for use as a lubricant base feedstock or as a blending feedstock with other lubricants, the reaction of this invention is carried out at a temperature higher (90-250 ° C) than the temperature suitable for the production of high molecular weight polyalphaolefins. The catalysts used in this invention do not cause a significant number of side reactions even at high temperatures when preparing oligomeric, low molecular weight liquids.

The catalysts of this invention thus minimize all side reactions and oligomerize alpha-olefins to produce 11,96775 23 low molecular weight polymers with high efficiency. It is well known in the prior art that Chromium oxides, especially chromium oxide with an average oxidation state of +3, catalyze either pure or supported double isomerization, dehydration, cracking, etc. Although the exact nature of the supported Cr oxide is difficult to determine, it is believed that this the catalyst of the invention is rich in silica-supported Cr (II), which is more active in catalyzing the oligomerization of alpha-olefin at high reaction temperature without causing significant amounts of isomerization, cracking or hydrogenation reactions, etc. However, the catalysts prepared in said literature references may have (III). They catalyze the polymerization of alpha-olefin at low reaction temperatures to produce high molecular weight polymers. However, as indicated in the literature references, undesirable isomerization, cracking and hydrogenation reactions occur at higher temperatures. In contrast, the present invention requires high temperatures to make lubricating products. The prior art also teaches that supported Cr-catalyzed cytes rich in Cr (II) or with higher oxidation states catalyze the isomerization of 1-butene with 103 times higher activity than the polymerization of 1-butene. The quality of the catalyst, the method of preparation, the treatments and the reaction conditions are critical to the performance of the catalyst and the composition of the product produced and distinguish this invention from the prior art.

The present invention uses very low catalyst concentrations based on the feed, 10-0.01 wt%; while said literature references use a 1: 1 ratio of catalyst to feed for the preparation of the high polymer. The use of smaller catalyst contents in the present invention to prepare a low molecular weight material is in contrast to conventional polymerization theory compared to the results obtained in said literature references.

The oligomers of 1-olefins prepared in this invention have much lower molecular weights than the polymers prepared in said literature references, which are semi-solids with very high molecular weights. These high polymers are not suitable as basic raw materials for lubricants and usually do not contain a detectable amount of dimeric or trimeric (^ ιο_ ^ 3ο) components from the synthesis.

Such high polymers also have very little unsaturation. However, the products of this invention are free-flowing liquids at room temperature which are suitable as a base raw material for the lubricant, contain a significant amount of dimer or trimer, and are rich in unsaturation.

The following examples of the present invention are presented for illustrative purposes only and are not intended to limit the scope of the present invention.

Example 1

Catalyst preparation and activation procedure 1.9 g of chromium (II) acetate (Cr2 (OCOCH3) 4.2H2O) (5.58 mmol) (obtained commercially) are dissolved in 50 ml of hot acetic acid. Thereafter, 50 g of silica gel with a mesh size of 8-12, an area of 300 m 2 / g and a pore volume of 1 ml / g are also added. The silica gel absorbs most of the 30 parts of the solution. The finished mixture is stirred for half an hour on a rotary evaporator at room temperature and dried in an open dish at room temperature. First, the dry solid (20 g) is purged with N 2 at 250 ° C in a tube oven. The oven temperature is then raised to 400 ° C for 2 hours.

The temperature is then set at 600 ° C by rinsing with dry air for 16 hours. At this point, the catalyst is cooled to 300 ° C under N 2. Pure CO (99.99%, manufactured by Matheson) of this residue flows in I! «96775 25 is entered for one hour. Finally, the catalyst is cooled to room temperature under N 2 and is ready for use.

5 Example 2

The catalyst prepared in Example 1 (3.2 g) is packaged in a 9.5 mm stainless steel tubular reactor in a dry box under N 2 shielding gas. The reactor is then heated under N2 to 150 ° C in a single zone Lindberg furnace. The pre-purified 1-hexene is pumped into the reactor at a pressure of 965 kPa and a rate of 20 ml / h. The liquid effluent is collected and the unreacted starting material and low-boiling material are distilled off at a pressure of 6.7 Pa. The viscosities and viscosity indices of the remaining clear colorless liquid are suitable as a basic raw material for the lubricant.

Nävte_Esiaio 1_2_3 T.O.S., h 2 3.5 5.5 21.5 20 Lubricant yield, p-% 10 41 74 31

Viscosity, mm 2 / s at 40 ° C 208.5 123.3 104.4 166.2 at 100 ° C 26.1 17.1 14.5 20.4

Viscosity index 159 151 142 143 25

Example 3

As in Example 2, a fresh sample of catalyst is charged to the reactor and 1-hexene is pumped into the reactor at a pressure of 101 kPa and a rate of 10 ml / h. As shown below, a lubricant having high viscosities and high viscosity indices is obtained. These runs show that under different reaction conditions a lubricant product with high viscosities can be obtained.

26 96775

Näyte_A_B

T.O.S., h 20 44 Temperature, ° C 100 50

Lubricant yield,% 8.2 8.0 5 Viscosities, mm2 / s at 40 ° C 13170 19011 at 100 ° C 620 1048

Viscosity Index 217 263 10 Example 4 A commercial chromium / silica catalyst containing 1% Cr on a high pore volume synthetic silica gel is used. The catalyst is first calcined with air at 800 ° C for 16 hours and reduced with CO at 300 ° C for 1.5 hours. 3.5 g of catalyst are then packed in a tubular reactor and heated to 100 ° C under N 2. 1-Hexene is pumped through at a rate of 28 ml / h at a pressure of 101 kPa. The products are recovered and analyzed as follows:

Näyte_C_D_E_F

T.O.S., h 3.5 4.5 6.5 22.5 lubricant yield,% 73 64 59 21

Viscosity, mm2 / s 25 at 40 ° C 2548 2429 3315 9031 at 100 ° C 102 151 197 437

Viscosity Index 108 164 174 199 These runs show that various Cr / silica catalysts are also active in the oligomerization of olefins to lubricant products.

Example 5

As in Example 4, purified 1-decene is pumped through the re-35 actuator at a pressure of 1830-2310 kPa. The product is recovered periodically and light products with boiling points below 243 ° C are distilled off. Li 96775 27 high quality products with high viscosity indices are obtained (see table below).

Reaction WHSV Lubricant Product Properties

5 1 - mode. ° C q / q / h V at 4 ° C_V at 100 °_VI

120 2.5 1555.4 mm2 / s 157.6 mm2 / s 217 135 0.6 389.4 53.0 202 150 1.2 266.8 36.2 185 166 0.6 67.7 12.3 181 10,197 0.5 21.6 5.1 172

Example 6

A similar catalyst is used to test the oligomerization of 1-hexene at different temperatures. 1-Hexene is fed at a rate of 28 ml / h and a pressure of 101 kPa.

Näyte_G_H

Temperature, ° C 110 200

Lubricant yield, wt% 46 3 20 Viscosities, mm 2 / s at 40 ° C 3512 3760 at 100 ° C 206 47 VI 174 185 25 Example 7 1.5 g of a catalyst similar to that prepared in Example 4 was added to a two-necked flask under N 2 atmosphere. .

Then 25 g of 1-hexene was added. The slurry was heated to 55 ° C under N 2 for 2 hours. A little heptane solvent was then added and the catalyst was removed by filtration. The solvent and unreacted starting material were distilled off to give a viscous liquid in 61% yield. The viscosities of this viscose liquid were 1536 and 51821 mm 2 / s at 100 ° C and 35 at 40 ° C, respectively. This example showed that the reaction could be carried out as a batch process.

96775 28

The 1-decene oligomers described below were synthesized by reacting purified 1-decene with an activated chromium / silica catalyst. The activated catalyst was prepared by calcining chromium acetate (1 or 3% 5 Cr) on silica gel at 500-800 ° C for 16 hours and then treating the catalyst with CO at 300-350 ° C for 1 hour. 1-Decene was stirred in the activated catalyst and heated to the reaction temperature for 16-21 hours. The catalyst was then removed and the viscous product was distilled to remove low boiling components at 200 ° C and 13.3 Pa.

The reaction conditions and results of HVI-PAO lubricant synthesis are summarized as follows: 15

table 1

Example Cr Silicon Calcinoin Treatment 1-Decene / Lubrication Dioxide Room Temperature Temperature Catalyst No. Surface Ratio 20 8 3 wt% 700 ° C 350 ° C 40 90 9 3 700 350 40 90 10 1 500 350 45 86 11 1 600 350 16 92 25 Branching ratios and lubricant properties of the alpha-olefin oligomers of Examples 8-11

Table 2

Example Branching V V

30 No. ratios of CH3 / CH2-40 ° C at 100 ° C VI

8 0.14 150.5 22.8 181 9 0.15 301.4 40.1 186 10 0.16 1205.9 128.3 212 11 0.15 5238.0 183.1 271

II

96775 29

Table 3

Example Branching V V

No. ratios of CH3 / CH2 at 40 ° C at 100 ° C VI

12 0.24 28.9 5.21 136 5 13 0.19 424.6 41.5 148 14 0.19 1250 100 168 15 0.19 1247.4 98.8 166 These samples were obtained from the commercial market. Niil-10 has higher branching ratios than the samples in Table 2. Likewise, they have lower viscosity indices than previous samples.

A comparison of these two sets of lubricants shows that oligomers of alpha-olefins, such as 1-decene, with branching ratios of less than 0.19, preferably 0.13-0.18, have higher viscosity indices and are better lubricants. . The branching ratios of the examples of this invention are 0.14-0.16, which provide lubricating oils of excellent quality with a wide range of viscosities between 3-483.1 mm 2 / s at 100 ° C and viscosity indices between 130-280.

Example 16 A commercial Cr / Silica catalyst containing 1% Cr on a high pore volume synthetic silica gel is used. The catalyst is first calcined with air at 700 ° C for 16 hours and reduced with CO at 350 ° C for 1-2 hours. 1.0 part by weight of activated catalyst is added to 200 parts by weight of 1-decene in a suitable reactor and heated to 185 ° C. 1-Decene is continuously fed to the reactor at a rate of 2-3.5 parts / min and 0.5 parts by weight of catalyst is added for every 100 parts of the 1-decene feed. After loading 1200 parts of 1-decene and 6 parts of catalyst, the slurry is stirred for 8 hours. The catalyst is filtered off and the light product, which boils below 150 ° C at a pressure of 13.3 Pa, is distilled off. The residual product is hydrogenated over Ni / diatomaceous earth catalyst at 200 ° C. The product has a viscosity of 18.5 mm 2 / s at 100 ° C, a viscosity index of 165 and a pour point of -55 ° C.

Example 17 Similar to Example 16 except that the reaction temperature is 125 ° C. The finished product has a viscosity at 145 ° C of 145 mm 2 / s, a viscosity index of 214 and a pour point of -40 ° C.

10 Example 18

Example 16 is repeated except that the reaction temperature is 100 ° C. The finished product has a viscosity at 29 ° C of 298 mm 2 / s, a viscosity index of 246 and a pour point of -32 ° C.

15 The final lubricant products of Examples 16-18 contain the following amounts of dimer and trimer and the isomer distributions are as follows:

Example_16_17_18 Viscosity at 100 ° C, mm 2 / s 18.5 145 298

Viscosity index 165,214,246

Freezing point, ° C -55 ° C -40 ° C -32 ° C

Dimer, p% 0.01 0.01 0.027 Isomeric distribution of dimer, wt% n-eicosan 51% 28% 73% 9-methylnonacosane 49% 72% 27% trimer, wt 5.53 0.79 0 , 27 3 0 Isomeric distribution of trimer, wt% 11-octyldocosan 55 48 44 9-methyl, 11-octylheneicosane 35 49 40 35 Other 10 13 16 il 31 96775 These three examples show that the new HVIs for a wide range of viscosities -PAOs contain structurally unique dimers and trimers in different ratios.

5 Molecular weights and molecular weight distributions are analyzed by high pressure liquid chromatography consisting of a high pressure Constametric IA twin-piston pump, manufactured by Milton Roy Co. and a Tracor 945 LC detector. During the analysis, the system pressure is 4600 kPa and the THF solvent 10 (HPLC grade) feed rate is 1 ml / min. The temperature of the detector block is set to 145 ° C. 1 ml of the sample prepared by dissolving 1 g of the PAO sample in 1 ml of THF solvent is injected into the chromatograph. The sample is eluted through the following columns in series, all 15 from Waters Associates: Utrastyragel 105 A, P / N

10574, Utrastyragel 104 A, PN 10573, Utrastyragel 10 ^ A, P / N 10572, Utrastyragel 500 A, PN 10571. The molecular weight is calibrated from Mobil Chemical Co. commercially available PAO products against Mobil SHF-61 and SHF-81 and SHF-401 20.

The following table summarizes the molecular weights and distributions of Examples 16-18:. 25 Examples_16_17_18

Viscosity at 100 ° C, mm 2 / s 18.5 145 298

Viscosity index 165,214,246

Number average molecular weight MWn 1670 2062 5990

Weighted average molecular weight MWw 2420 4411 13290 30 Molecular weight distribution, MWD 1.45 2.14 2.22

Under similar conditions, an HVIPAO product can be prepared with a viscosity of only 3 mm2 / s and up to 50 mm2 / s and a viscosity index between 130-280.

Ethylene can be used as a starting material for the conversion to higher C8-C20'alpha "olefins by a conventional catalytic procedure, for example by contacting ethylene with a Ni catalyst at 80-120 ° C and about 7000 kPa using the commercial synthetic methods described in Chem. System Process Evaluation / -Research Planninq Report - Alpha-Olefins, Report No. 5 82-4 The intermediate olefin has a wide distribution range between C8-C20 carbon atoms.

The full range of alpha-olefins from the growth reaction or a partial range such as C8-C14 can be used to prepare lubricating oil in high yields and high viscosity indices. After hydrogenation, the oligomers have low pour points.

Example 19 An alpha-olefin growth reaction mixture as described above containing equal molar concentrations of C8-C8-C10-C14'C16'C18'C20 'fractions is reacted with 2% by weight of activated Cr / SiO2 catalyst at 130 ° C and in a nitrogen atmosphere. After a reaction time of 225 minutes, the catalyst is filtered off and the reaction mixture is distilled to remove a light fraction boiling below 120 ° C in 13.3 ° C. The residual oil has a yield of 95% and a viscosity at 67 ° C of 67.07 mm 2 / s and a viscosity index of 195.

25 Example 20

The equimolar C8-C20'alpha-° lefin mixture described above is continuously fed over an activated Cr / SiO2 catalyst packed in a tubular reactor. The results are summarized in the following table.

it 96775 33

Table 20

Samples Starting material A B C D

Temperature 1a, 0C - 125 150 190 200 5 Pressure, kPa - 2238 2170 1825 2032 WHSV, q / q / h - 1.2 1.2 1.2 1.2

Product "distribution, p-% 1-C6 = 4.7 0.3 0.3 0.5 1.1 l-Ce1 12.8 0 0.3 1.1 2.3 10 1 -Ci o :: 22 .0 1.8 1.8 2.3 4.6 1-Ci 2 19.4 0.3 0.5 1.4 3.4 1-C 14 "16.0 0.9 0.9 1.9 4 .8 1-Ci er 11.0 0.6 0.4 1.9 4.3 1-Cie- 7.7 0.8 1.3 2.7 6.0 15 1-C? o "6.5 0.5 1.8 3.1 6.9 C20 -C30 O 4.4 2.6 7.8 18.7

Lubricating oil 0 90.5 90.1 78.5 47.5

Properties of lubricating oil 20 Viscosity at 100 ° C mm2 / s - 75.11 51.24 12.12 14.86

Viscosity Index - 190 184 168 164 25 Example 21

An equimolar mixture of Ce-Ce-C 1 -C 10 -C 4 acyl olefins is reacted over a similar Cr / SiO 2 catalyst as in Example 2. The results are summarized in Table 21.

96775 34

Table 21

Samples Starting material A BCD

Temperature, ° C - 120 150 190 204 5 Pressure, kPa - 1825 1549 1480 1480 WHSV, g / g / h - 2.5 2.5 2.5 2.5

Product distribution, wt% 1-C6 = 16.3 0.3 0.6 1.2 6.9 1-C8 = 25.0 0.5 1.1 1.8 4.3 10 1-C10 = 26, 3 5.6 2.9 2.7 10.9 1-C12 = 19.9 0.5 0.9 1.5 9.1 1-C14 = 12.4 0.0 1.1 3.2 7, 4 C20-C30 0 0.0 5.1 23.8 18.7

Lubricating oil 0 93.0 88.4 65.8 42.7 15

Voiteluöljyominaisuu-det

Viscosity at 100 ° C mm 2 / s - 101.99 46.31 17.97 7.31 20 Viscosity index - 187 165 168 157 Freezing point after H2 treatment, -33 -43 -58 -41

° C

25 A series of alpha-olefins from ethylene growth reactions and metathesis processes can be used to produce a high quality lubricating oil by this process, making the process cheaper and the feedstock more flexible than the use of pure single monomer.

30

Example 22

The standard 1-decene oligomerization synthesis procedure used above is repeated at 125 ° C using various Group VIB metals, tungsten or molybdenum. The W / Mo-treated 35 porous support is reduced with CO at 460 ° C to give 1% by weight of metal in the reduced oxide state. The molybdenum catalyst gives a 1% yield of viscous liquid. Wolfram only gives the C2Q dimer.

li: 96775 35

The use of supported oxides of Group VIB metals as a catalyst in the oligomerization of olefins for the preparation of low branching ratio and low pour point lubricant-5 products was not previously known. The catalytic preparation of oligomers with a low branching ratio, which do not use corrosive cocatalysts and which produces a lubricant with a wide viscosity range and good viscosity indices was also not previously known, and more specifically the preparation of lubricants with the degree of branching is less than 0.19, was also not previously known.

Although the present invention has been described in terms of preferred embodiments, it is to be understood that variations and variations may be employed without departing from the spirit and scope of the present invention, as will be readily understood by those skilled in the art. Such modifications and variations are considered to be within the scope and scope of the appended claims.

Claims (24)

36 96775 A liquid lubricant composition consisting of C30-C1300 hydrocarbons, characterized in that it has a branching ratio of between 0.1 and 0.16, a weight average molecular weight of between 5,300 and 45,000, a number average molecular weight of between 300 and 18,000, a molecular weight distribution of between 1-5 and a pour point below -15 ° C. A composition according to claim 1, characterized in that said hydrocarbons consist of C30-C1000 hydrocarbons and have a molecular weight distribution of 1.05-2.5. Composition according to Claim 1, characterized in that said hydrocarbons consist of alkanes or alkenes. Composition according to Claim 1, characterized in that it has a viscosity index of more than 130 and a viscosity at 100 ° C of between 3 and 750 mm 2 / s. 20 Composition according to Claim 1, characterized in that it has a C30 fraction, a viscosity index of more than 130 and a pour point of less than -45 ° C. Composition according to Claim 1, characterized in that; that the composition comprises a polymeric residue of 1-alkenes taken from linear C6-C20-1-alkenes. Composition according to claim 6, characterized in that said 1-alkenes consist of c8-c12 alkenes. Composition according to claim 6, characterized in that said polymeric residue comprises a hydrogenated polymeric residue of said 35 1-alkenes. Il 96775 37 Composition according to claim 6, characterized in that said polymeric residue consists of poly-1-decene. Composition according to Claim 9, characterized in that the polymeric residue of the 1-decene has a molecular weight of approximately 422. Composition according to Claim 10, characterized in that it has a viscosity index of approximately 134 and a pour point of less than -45 ° C. A liquid lubricant hydrocarbon composition according to claim 1, characterized in that it has a repeating polymer structure [-CH 2 -CH-] <k>. i ch3 where n is 3-17 and x is 5-500. 20 Composition according to Claim 12, characterized in that n is 7 and x is on average at least 15. Composition according to Claim 12, characterized in that it has a viscosity index of more than 130 and a freezing point of less than -15 ° C. A lubricant hydrocarbon composition according to any one of the preceding claims, characterized in that The CI300 hydrocarbons consist of 9-methyl, 11-octylhenecosan and 11-octyldococane. Composition according to Claim 15, characterized in that the molar ratio between 9-methyl, 11-octylhenecosanane and 11-octylidenocosan is between 1:10 and 10: 1. Composition according to Claim 16, characterized in that said molar ratio is preferably 1: 2 to 2: 1. 96775 38 Composition according to Claim 15, characterized in that the 11-octyldocosan has the structure: H 50 O (O) 10 C (CH 2) 9 CH 3 (CH 2) 7 ch 3 Process for the preparation of liquid hydrocarbons according to claim 1, suitable as lubricating raw materials, from alpha-olefins having 6 to 20 carbon atoms or mixtures of such olefins, characterized in that said olefins are brought under oligomerization conditions at a reaction temperature of about 90 to 250 ° C - a chromium catalyst having 15 which has been treated by oxidation at a temperature of 200 to 900 ° C in the presence of an oxidizing gas and then treated with a reducing agent at a sufficient temperature and sufficient time to reduce said catalyst to a lower valence state to give an oligomeric liquid lubricant; consists of C30-C1300 hydrocarbons having a branching ratio of 0.1 to 0.16, a weight average molecular weight of 300 to 45,000, a number average molecular weight of 300 to 18,000, a molecular weight distribution of 1 to 5 and 25 the pour point is below -15 ° C. % Process according to claim 19, characterized in that said reducing agent consists of CO, the oligomerization temperature is about 100-180 ° C and the yield of C 3 O + oligomer is at least 85% by weight for a product having a viscosity of at least 15 mm 2 / s 100 ° C. Process according to Claim 19 or 20, characterized in that the support material consists of porous silica. Process according to Claim 19, 20 or 21, characterized in that the olefin consists essentially of 1-octene: 96775 39 tene, 1-decene, 1-dodecene, 1-tetradecene or mixtures thereof. A process according to claim 19, 20, 21 or 22, characterized in that said catalyst is not subjected to a further oxidation step after said reduction. Process according to claim 19, 20 or 21, characterized in that said olefin consists of 1-decene 10 and the viscosity index of the oligomer is 181 or more and the branching ratio is 0.14-0.16.