FI93369C - Process for the oligomerization of C4 olefins with linear alpha-olefins - Google Patents

Description

93369

The present invention relates to a process according to the preamble of claim 1 for the production of synthetic oils.

According to this method, olefinic hydrocarbons are polymerized to produce petroleum products having a number average molecular weight of typically 10 to 1200.

The invention also relates to copolymers according to the preamble of claim 17, which are suitable for use as synthetic oils, as well as to a process for the preparation of such copolymers.

After isolation of 1,3-butadiene and isobutene from pyrolytic fractions in the petrochemical industry, a mixture called raffinate II is obtained. This type of mixture is formed, for example, in the production of polyisobutene and in particular in the production of methyl tert-butyl ether (MTBE) as an anti-knock agent for petrol. In addition to n-butane and isobutane, raffinate II comprises considerable amounts of n-butenes, so that the usual raffinate composition 25 contains about 30 to 55% by weight of 1-butene and 15 to 30% by weight of 2-butenes (i.e. cis- and trans-butenes) .In addition, it contains small amounts, typically less than 3% by weight, of isobutene and some (e.g. less than 3% by weight) methanol.

30 The production of polyisobutylene and MTBE usually produces large amounts of raffinate II, which is used in low-value-added sites. In this connection, the use of raffinate II or similar inexpensive starting materials for the preparation of synthetic oils has been proposed in the prior art. EP-A-0 337 737 and EP-A-367 386 disclose a process for the preparation of poly-n-butene oils which comprises oligomerizing the olefinic C4 hydrocarbons of raffinate II in a reaction carried out with an initiator such as AlCl3 or 2,9369 alkylaluminum chlorides. and in the presence of a coinitiator, typically HCl. Since raffinate II does not contain isobutene, or contains it in concentrations of less than 3% by weight, the oils produced mainly comprise copolymers of 1-butenes with cis- and trans-2-butenes.

Although poly-n-butene oils are not yet industrially produced on a large scale, it can be assumed that they will be widely used in the future because they can be produced from inexpensive starting materials such as raffinate II.

At the same time, however, it should be noted that these oils have the disadvantage of a strong temperature dependence of their viscosity, which today limits the use of poly-n-butene oils as motor lubricating oils or in similar applications.

15

The quality of lubricating oils is usually characterized by a pour point and a viscosity index. The latter describes the temperature dependence of the viscosity of the oil. High quality synthetic oils for engine lubricating oils are normally required to have a viscosity index greater than 120. These values are obtained with conventional polyolefin oils produced by oligomerization of higher linear alpha-olefins with Friedel-Crafts using catalysts.

These oils are prepared in particular by oligomerization (i.e. trimerization ... pentamerization) of 1-octene or 1-decene to give oligomers with optimal properties both in terms of their viscosity index and their pour point. By way of comparison, it can be mentioned 30 that poly-n-butene-based oils have a viscosity index of less than 75, a value which, although too low for motor lubricant oil use, is still high enough for many other applications.

35 Oils produced from higher linear olefins are among the most expensive petroleum products on the market, which limits their widespread use.

: i Utit i'tfc l> -t · «** · · 3 93369

In conclusion, conventional synthetic oils are too expensive to be used on a larger scale, while the properties of the much more preferred poly-n-butene oils do not meet the standards of engine lubricating oils.

The object of the present invention is to obviate the drawbacks associated with known synthetic lubricating oils and to provide a completely new type of preferred oils with acceptable properties.

It is also an object of the invention to provide novel olefinic copolymers which can be used as lubricating oils or as part of synthetic oils.

15

It is a further object of the invention to provide a process for the preparation of new oils and copolymers.

It has now surprisingly been found that 1-butene and cis- and trans-2-butenes or mixtures thereof in raffinate II can be easily copolymerized with higher linear alpha-olefins in the presence of suitable initiators to produce an oil product having a high viscosity index and low pour point. The invention is therefore based on the idea that higher linear alpha-olefins are copolymerized in hydrocarbon compositions containing substantial amounts of olefinic C4 hydrocarbons. In particular, they are copolymerized in a composition comprising a residue of a pyrolytic C4 fraction, such as the aforementioned * '' raffinate II.

More specifically, the method according to the invention is characterized by what is set forth in the characterizing part of claim 1.

The copolymers according to the invention, in turn, are characterized by what is stated in the characterizing part of claim 17.

The process for preparing copolymers useful as synthetic oils is characterized by what is set forth in the characterizing part of claim 5.

In the context of the present invention, the term "polymerize" refers to the formation of large molecules through chemical reactions from individual monomers (i.e., repeating units) regardless of the number of monomers present in the product. Thus, in the present application, the term "polymerization" also includes "oligomerization", i.e. the formation of molecules containing 2 to 10 monomers.

In a preferred embodiment, synthetic oils are prepared by polymerizing higher linear alpha-olefins (LAO) in hydrocarbon compositions containing about 15 to 80% by weight of 1-butene, 5 to 50% by weight of 2-butenes, and about 10% by weight. % by weight or less of isobutene. The hydrocarbon compositions preferably contain about 25 to 70% by weight, particularly preferably 30 to 60% by weight of 1-butene, and 10 to 40% by weight, particularly preferably 15 to 30% by weight. 2-butene. In addition to these components, the composition may contain small amounts of e.g. n-butane, isobutane, propane or other alkanes, isobutene, methyl tert-butyl ether and other etherification products, as well as various other lower olefinic oligomers.

Olefinic hydrocarbons consist in particular of hydrocarbon mixtures which remain in the pyrolytic C4 fractions after isolation of 1,3-butadiene and isobutene. Hydrocarbon mixtures of this type may consist of raffinate II obtained from the production of methyl tert-butyl ether or the selective polymerization of isobutene.

1 to 99% by weight, preferably 5 to 90% by weight and particularly preferably 10 to 70% by weight of higher LAO compounds are added to the C4 hydrocarbon mixtures. The amount of linear alpha-olefins added is then calculated from the total amount of olefins in the mixture formed after the addition. The added LAOs comprise higher alpha-olefins having 6 to 24 carbon atoms. Preferably the LAOs are higher linear alpha-olefins having 6 to 18 carbon atoms, particularly preferably the LAOs consist of higher linear alpha-olefins having 8 to 16 carbon atoms. Examples of LAO include 1-octene, 1-decene, 1-dodecene, Ι-ΙΟ tetradecene and 1-hexadecene.

The molecular weights of the copolymers produced vary depending on the composition of the starting material mixture, the polymerization temperature and, to some extent, the initiator system used. Typically, the number average molecular weight, Mn, ranges from 300 to 1200, preferably from about 350 to about 1000.

Preferably, the polymerization is carried out at -10 ° C to + 70 ° C. Without changing the composition of the reaction mixture, the number average molecular weight of the copolymers can be changed between 300 and 1000 by varying the polymerization temperature.

Initiator systems similar to those previously used to prepare poly-n-butenes can be used for polymerization. Reference should be made in this connection in particular to the above-mentioned EP-A-0 337 737 and 0 367 386, the contents of which are incorporated herein by reference.

30 The initiator system may be AlCl3 based. However, the copolymerization does not proceed with AlCl 3 alone, which is why, in a preferred embodiment, AlCl 3 is added in a solution of ethyl chloride or in a liquid complex formed from AlCl 3 in toluene or a similar aromatic solvent and hydrogen chloride. These forms of AlCl3 have the advantage of easy dosing of the initiator into the reaction system. Another advantage is that AlCl3 does not require any additional coinitiators if added in the form shown.

Since the liquid complex of aluminum trichloride is not soluble in raffinate II, the reaction medium must be stirred vigorously to avoid precipitation of the catalyst system 5 at the bottom of the reaction vessel.

According to another preferred embodiment, an alkylaluminum chloride of the general formulas R2A1Cl or RA1Cl1 is used as the initiator and anhydrous hydrogen halide is used as the co-initiator of the polymerization. In the above general formulas, R represents Lower alkyl having 1 to 6 carbon atoms. Preferably, alkylaluminum dichloride compounds of the general formula RA1C12 are used, and in particular methylaluminum dichloride, ethylaluminum dichloride, propylaluminum dichloride or butylaluminum dichloride is selected as the compound. Suitable hydrogen halides are hydrogen chloride and hydrogen fluoride, in which case hydrogen chloride is preferred.

The gradual addition of the initiator to the reaction mixture can contribute to the progress of the copolymerization reaction, since this results in a practically isothermal control of the strongly exothermic copolymerization reaction. In this way, it is possible to ensure that a uniform product is obtained.

When using an initiator system comprising an initiator and a coinitiator, it is preferred to add a coinitiator at the beginning of the polymerization. If anhydrous hydrogen chloride is used, the total amount of coinitiator initially added is 0.1 to 0.3% by weight. The coinitiator can be added dissolved in the reaction mixture. The alkylaluminum dichloride can then be added in small portions, preferably in an inert solvent, causing the polymerization to proceed almost isothermally at the desired temperature. If the ingredients are added in reverse order, there is a risk that the exothermic reaction cannot be controlled, so that it proceeds very rapidly. This can lead to undesired overheating of the reaction mixture.

93369 7

The polymerization reaction consumes initiator and coin initiator. At polymerization temperatures below -10 ° C, the relative consumption of the initiator increases and then little conversion is achieved. Thus, as mentioned above, reaction 5 is preferably carried out at temperatures above -10 ° C. Typically, the consumption of initiator is 0.3 to 0.7% by weight (of the product obtained) when the temperature is in the preferred temperature range of -10 ° C to + 70 ° C and the olefin conversion exceeds 90%.

10

According to a particularly preferred embodiment, alpha-olefins having from 6 to 18 carbon atoms in the molecule are added to an olefinic hydrocarbon mixture containing a total of at least 30% by weight of n-butenes. Alpha-olefins 15 are reacted with butenes in the presence of an initiator system comprising AlCl3 dissolved in ethyl chloride or a liquid complex of AlCl3, toluene and HCl to give oils having viscosities of 100 to 150 and pour points are 20 +5 ° C ...- 65 ° C. The molar ratio of alpha-olefins to n-butenes is 1: 1 to 1: 5.

According to another particularly preferred embodiment of the invention, alpha-olefins having from 8 to 16 carbon atoms in the molecule are added to an olefinic hydrocarbon composition containing a total of at least 30% by weight of n-butenes. The alpha-olefins are reacted with the butenes of the hydrocarbon mixture in the presence of an initiator system comprising alkylaluminum dichloride together with hydrogen chloride to give an oil having a viscosity index of 100 to 140 and a pour point of 0 ° C to -65 ° C. The molar ratio of alpha-olefins to n-butenes is 1: 1 to 1: 5.

The copolymers of the invention consist essentially of repeating units of n-35 butenes, cis- and trans-2-butenes and higher linear alpha-olefins containing 6 to 18 carbon atoms. The polydispersity of these copolymers is 8,93636

Expressed as a ratio of Mw / Mn is less than 1.4.

As mentioned above, the invention also relates to a process for preparing a useful copolymer 5 as a synthetic oil or a part thereof. In summary, the process comprises the following steps: - mixing higher linear alpha-olefins having from 6 to 18 carbon atoms with a mixture of C4 hydrocarbons from the production of methyl tert-butyl ether or the selective polymerization of isobutene and which contains at least 15% by weight of 1-butene and at least 5% by weight of 2-butenes, to form a reaction mixture, - an initiator system is added to the reaction mixture, 15 - the temperature of the reaction mixture is kept at -10 to + 70 ° C, - higher linear alpha -olefins are reacted with 1-butenes and 2-butenes to form a reaction product, and - the volatile components and any residues of the initiator system are separated to form an oily product consisting mainly of copolymers with a number average molecular weight of 300-1200.

The petroleum products of the invention typically have a higher viscosity index than poly-n-butene oils as such. Copolymerization of n-butenes with higher linear alpha-olefins also improves the pour point of the products. The present oils have a lower pour point than poly-n-butene oils and are even lower than oligomers of higher linear alpha-olefins of corresponding molecular weight.

According to a preferred embodiment of the present invention, the hydrocarbon composition may contain up to small amounts of methanol, since methanol may affect the polymerization reaction by consuming the initiator and preventing polymerization.

93369 9

Thus, if raffinate II from the production of methyl tert-butyl ether is used, which may sometimes contain up to a few% by weight of methanol, the residual methanol must be completely removed or reduced to less than 3000 ppm before the polymerization reaction.

The viscosity index of the copolymer varies depending on the higher linear alpha-olefins used and their concentration. The viscosity index increases with increasing concentration and length of linear alpha-olefins. The pour point of the resulting copolymer also depends on the higher linear alpha-olefin used and increases as the length of the copolymer molecule increases and the molar amount of n-butenes increases.

15

After the polymerization, the reaction mixture is worked up by methods known per se. According to a preferred embodiment, it is washed, in particular with about 5% aqueous soda solution and then with water. Alternatively, about 0.5 to 10%, especially about 2%, of the initial concentration of olefins is added to the mixture of sorbent alumina to remove the catalyst. The low-boiling product fractions are distilled off by heating to at least 140 ° C at a pressure of 13 Pa. This gives a colorless or slightly yellowish oil with a kinematic viscosity of 4 to 15 cSt at + 100 ° C and 27 to 160 cSt at + 40 ° C. The resulting copolymers are characterized by a relatively narrow molecular weight distribution corresponding to a polydispersity t-index of less than 1.4 expressed as molecular weight distribution M

30

The invention provides considerable advantages. Thus, a particularly important advantage of the present invention is that the copolymerization of n-butenes can be performed in raffinate II, an inexpensive secondary feedstock that is normally discarded without the need to isolate and purify the n-butenes.

93369 10

A further advantage of the invention is the possibility to produce high quality synthetic oils with the same viscosity numbers as expensive synthetic oils made from pure higher linear alpha-olefins.

Those oils prepared by copolymerizing n-butenes with higher linear alpha-olefins according to the present invention are suitable for many applications. Due to their highly suitable viscosity indices and pour points, they can be used in particular as high-quality engine lubricating oils in applications where the change in viscosity as a function of temperature should be as small as possible. The low molecular weight ratio Μ ,, / Μ ,, 15 is an important indication that the viscosity of the oil will not change very much under long-term mechanical stress. The properties obtained are similar to those with long-life multigrade oils.

Another important feature of the present oils is that they do not leave significant annealing residues when heated to a high temperature or burned. For this reason, it can be assumed that they will be used as lubricating oils in two-stage internal combustion engines, in metallurgy as suitable oils for rolling and drawing metals, transformer oils, in electrical insulation and cables, as energy transmission oils for cooling and heating systems and many other similar applications. The oils are non-toxic and can be used as additives for plastics and rubbers.

In the following, the invention will be examined in more detail by means of application examples which illustrate the copolymerization of n-butenes with higher linear alpha-olefins 25 in raffinate II. It is to be understood, however, that the scope of the invention is not limited to these examples. In particular, it should be noted that other hydrocarbon compositions containing substantial amounts of olefinic C4 hydrocarbons may be used in the present invention.

Equipment and materials 5

The copolymerizations were carried out in a glass reactor with a volume of 150 ml or alternatively in a stainless steel reactor with a volume of 1000 ml. Both reactors were equipped with a magnetic stirrer, a valve-10 steam to add and dispense the initiator, and external cooling. The temperature of the reaction mixture was monitored with a thermocouple connected to a recorder. The progress of the polymerization was monitored by the gradual addition of initiator to maintain the temperature of the reaction mixture to the desired temperature to the nearest +3 ° C.

A hydrocarbon composition (raffinate II) comprising the residue of the C4 fraction of MTBE production is used to make the oils. It was washed three times with water to remove methanol and dried as a liquid over KOH in a pressure vessel.

The composition of the hydrocarbon product thus treated was as follows: 49.2% 1-butene, 15.1% trans-2-butene, 9.7% cis-2-butene, 2.2% isobutene, 15.6% n-butane , 7.2% isobutane and 0.6% Propane. The methanol content was always less than 3000 ppm and the concentration of methyl tert-butyl ether was less than 0.2%. The linear alpha-olefins were of commercial purity and contained more than 99% by weight of 1-olefin.

The molecular weights Mn and M * of the products and the molecular weight distribution Mw / Mn were determined by GPC and VPO.

35

Example 1 12 93369 The copolymerization of N-butenes was carried out from a hydrocarbon mixture called raffinate II isolated from C4 and -5 in the production of MTBE. To this mixture was added 30 mol% of 1-decene, whereby the amount of 1-decene to be added was calculated on the basis of the olefins in the new mixture formed. The copolymerization was carried out at an average temperature of + 20 ° C by gradually adding small amounts of a 10% solution of 10 AlCl 3 in ethyl chloride so that the reaction mixture only overheated at a maximum of 3 ° C. The polymerization was stopped after 40 minutes by the addition of alcohol, after which the reaction mixture was washed with 5% sodium hydroxide solution and then with water. The hydrocarbon layer was separated, mixed with diatomaceous earth and filtered under pressure. The volatile fraction was removed by heating the reaction mixture to 120 ° C at 13 Pa. The colorless oil obtained had a number average molecular weight Mn of 810 and a viscosity index of 107. Based on the final product, the consumption of AlCl3 was 0.6% by weight, with an olefin conversion of 97% by weight.

Example 2 • Copolymerization of N-butenes with 1-dodecene was carried out in 25 raffinate II in the same manner as in Example 1. The copolymer prepared from 30 mol% of 1-dodecene at a polymerization temperature of + 20 ° C had a molecular weight Mn of 850 and a viscosity index of 122. and the solidity was -43 ° C. The consumption of AlCl 3 was 0.7% by weight with a conversion of 95%.

30

Example 3

The copolymerization of the n-butenes in the raffinate II was carried out by adding 30 mol% of 1-tetradecene in the same manner as in Example 1, the oil obtained at a polymerization temperature of +20 ° C having a molecular weight Mn of 810. Its molecular weight distribution Μ * / Μ „was 1 , 3 and the viscosity index was 141.

Example 4 93369 13 5 The copolymerization of N-butenes was carried out in the residue of the C4 fraction (raffinate II) by adding 30 mol% of 1-hexadecene (the amount of addition is indicated relative to the total amount of olefins in the same manner as in Example 1). The copolymerization was carried out at + 20 ° C to give a conversion of 92% (calculated on the basis of the olefins in the mixture). The prepared oil had a number average molecular weight Mn of 910, a molecular weight distribution of 1.1, a viscosity index of 148 and a pour point of -3 ° C. The consumption of AlCl 3 was 0.65% by weight at a conversion level of 92%.

15

Example 5 Copolymerization of the n-butenes in the C4 fraction was performed by adding 30% by weight of 1-hexadecene at + 20 ° C using a ground liquid complex for initiation from AlCl 3, toluene and anhydrous HCl. The liquid complex was prepared by feeding HCl gas to a suspension of 5.0 g of AlCl 3 in 6.0 mL of toluene at 0 ° C until all of the AlCl 3 had passed into solution. Gradual addition of initiator to the reaction mixture over 30 minutes resulted in 94% conversion.

The resulting oil had a molecular weight Mn of 700, a molecular weight distribution Mw / Mn of 1.31, a viscosity index of 130 and a pour point of -15 ° C. The consumption of AlCl3 relative to the product was 0.6% by weight.

30

Example 6 The copolymerization of N-butenes was carried out in the residue of the C4 fraction by adding 50% by weight of 1-decene at + 70 ° C. An AlCl3 liquid complex prepared according to Example 5 was used as the Initi-35 initiator system. The polymerization was stopped after 30 minutes by the addition of alcohol with a conversion of 93.5% 14 93369. The oil product had a molecular weight Mn of 560, a viscosity number of 117 and a pour point of -38 ° C.

Example 7 Copolymerization of N-butenes was carried out in raffinate II by adding 30% by weight of the total olefin mixture of the 1-dodecene mixture formed. A liquid complex of AlCl 3 prepared as in Example 5 was used for initiation. The copolymerization was allowed to proceed at -10 ° C for 50 minutes gradually with the addition of initiator until 85% conversion of olefins was achieved. The resulting copolymer had a molecular weight of Mn of 860, a viscosity number of 105 and a pour point of -31 ° C. Based on the product, the consumption of AlCl3 was 0.83% by weight.

Example 8

The n-butenes in raffinate II were copolymerized with linear C6-C6. . With C16 alpha-olefins, the latter being added to the reaction mixture in an amount of 37% by weight of the total olefins contained in the newly formed mixtures. The polymerizations were carried out at + 20 ° C using an ethyl chloride solution of AlCl 3 as initiator. The consumption of AlCl 3 relative to the amount of product was 0.45 0.75% by weight. The results are reported in Table 1.

93369 15

Table 1 Properties of copolymers prepared from n-butenes in raffinate II and various 1-olefins (about 37% by weight 1-olefin, 20 ° C) 5-l-Ole- Conversion Molecular Kinematic Viscosity Solids% viscosity point

M „M * [cSt] number ° C

40 100 10 _ C4 83.3 620 740 156.0 12.9 66 C6 92.5 690 820 155.1 13.8 82 C8 - 750 840 147.6 13.7 87 15 89.4 680 800 131.3 12.8 88 C10 94.0 660 810 98.5 10.9 94 C12 93.8 760 910 109.0 12.2 102 -38 C14 96.4 680 860 64.9 9.3 122 -33 C16 95 4,680,860 56.5 8.6 127 -16 20 _

Polymerization conditions: initiator - aluminum chloride in ethyl chloride at a polymerization temperature of +20 ° C The content of 1-olefins (C4-C16) refers only to the raffinate. , To the olefins in II

Example 9 Copolymerization of N-butenes was performed on a mixture of C4 hydrocarbons (raffinate II) obtained from the production of MTBE.

::: To this mixture was added 37% by weight of 1-decene, the amount of addition being calculated on the basis of the total amount of olefins in the mixture formed. Prior to polymerization, 0.3% by weight of gaseous hydrogen chloride was introduced into the reaction mixture. The copolymerization was carried out at an average temperature of + 20 ° C by gradually adding small amounts of a 10% heptane solution of EtAlCl 2 so that the mixture did not overheat by more than 3 ° C. The polymerization was stopped after 40 minutes by the addition of alcohol, whereupon the reaction mixture was washed with 5% sodium hydroxide solution and then with water. The hydrocarbon layer was separated, mixed with diatomaceous earth and filtered under pressure. The volatile fraction was removed by heating the reaction mixture to 120 ° C at 13 Pa. The resulting colorless oil had a number average molecular weight of Mn of 640 and a viscosity index of 97. Relative to the final product, the consumption of EtAlCl 2 was 0.5% by weight with an olefin conversion of 92%.

Example 10 N-butenes were copolymerized with 1-dodecene in raffinate II in the same manner as in Example 9. The copolymer prepared from 1-dodecene (37% by weight) at a polymerization temperature of + 20 ° C had a molecular weight Mn of 111 and a pour point of -38 ° C. The consumption of EtAlCl 2 was 0.7% by weight with 93% conversion.

Example 11

The copolymerization of the n-butenes in the raffinate II was carried out by adding 37% by weight of 1-tetradecene in a manner similar to Example 9. The molecular weight Mn of the oil obtained at the polymerization temperature +20 ° C was 630, the molecular weight distribution Μ * / Μη 1.2, the viscosity the index was 109 and the pour point was -33 ° C.

25

Example 12 Copolymerization of N-butenes was carried out in the residue of the C4 fraction (raffinate II) by adding 37% by weight of 1-hexadecene relative to the total amount of olefins in a manner similar to Example 9 at + 20 ° C. The prepared oil had a number average molecular weight Mw of 820, a molecular weight distribution Μ * / Μπ of 1.25, a viscosity index of 110 and a pour point of -16 ° C. The consumption of EtAlCl2 was 0.65% by weight at a conversion level of 91%.

Initially, 0.25% by weight of anhydrous hydrogen chloride was added to the reaction mixture.

s · ii au.i iin i iin, i

Example 13 93369 The n-butenes in the residue of the 17 C4 fraction are copolymerized by adding 13% by weight of 1-hexadecene at + 20 ° C using anhydrous HCl and EtAlCl 2 as the initiator system. A conversion level of 89% was achieved by gradually adding the initiator to the reaction mixture over 30 minutes. The resulting oil had a molecular weight Mn of 680, a molecular weight distribution Rf / Mn of 1.15, a viscosity index of 83 and a pour point of -45 ° C. At a ratio of 10 to EtAlCl2, the consumption of EtAlCl2 was 0.6% by weight.

Example 14 Copolymerization of N-butenes was performed at residue 15 of the C4 fraction by the addition of 50% by weight of 1-decene at + 70 ° C. HCl and EtAlCl2 are used as initiators. The polymerization was stopped after 30 minutes by adding alcohol at a conversion level of 93.5% by weight. The oil product had a molecular weight Mn of 560, a viscosity index of 119 and a pour point of -63 ° C.

20

Example 15 Copolymerization of N-butenes was performed in raffinate II by adding 30% by weight of 1-octene relative to the total amount of olefin in the resulting mixture and using EtAlCl 2 as initiator. The copolymerization was allowed to proceed at -10 ° C for 50 minutes with the gradual addition of initiator until a conversion of 85% by weight of the total olefins was achieved. The resulting copolymer had a molecular weight Mn of 860, a viscosity index of 105 and a pour point of -21 ° C. Based on the product, the consumption of EtAlCl2 was 0.83% by weight. 0.35% by weight of anhydrous hydrogen chloride was initially added to the reaction mixture.

Example 16

The copolymerization of n-butene in raffinate II was carried out by adding 37% by weight of linear C6-3518 93369 to the reaction mixture. . .C16-alpha-olefins. The amount of olefin addition is calculated from the total amount of olefins in the new mixture. Polymerizations were performed at + 40 ° C using EtAlCl 2 solution and HCl as coinitiator as initiator. Calculated from the product, the consumption of EtAlCl2 was 0.40 ... 0.70% by weight. The results are reported in Table 2.

Example 17 The copolymerization of n-butenes in raffinate II was carried out by adding 10% by weight of 1-octene and 10% by weight of 1-decene at + 20 ° C. Anhydrous HCl and methylaluminum dichloride, MeAlCl2 were used as initiator. The polymerization is stopped at a conversion level of 93% by weight. The consumption of MeAlCl 2 relative to product 15 was 0.65% by weight, giving an oil product with a number average molecular weight (Mn) of 610, a viscosity index of 95 and a pour point of -55 ° C.

Example 18 20

A mixture of n-butanes in raffinate II was copolymerized with 50% by weight of 1-decene using HCl and butylaluminum dichloride, BuAlCl 2, as the initiator system at + 50 ° C.

25

The isolated polymer had a molecular weight Mn <550, a viscosity index of 108 and a pour point of -51 ° C. The consumption of BuAlCl 2 was 10.73% by weight with an olefin conversion of 92% by weight.

30 93369 19

Table 2 Properties of copolymers of n-butenes and various 1-olefins in raffinate II (about 37% by weight of 1-olefin, 40 ° C) 5 1-Ole- Conversion Molecular Kinematic Viscosity- Solids-weight% viscosity - piste

Mn Mw [cSt] number ° C

40 100 10___ C4 89.9 560 690 68.4 7.9 74 C6 90.9 490 610 40.3 5.8 78 C8 95.2 520 620 45.8 6.7 98 15 C10 100.0 570 720 48 , 6 7.0 99 C12 83.2 500 680 25.1 4.7 107 -61 C, 4 92.3 530 700 26.3 5.0 115 -41 Cl6 90.8 660 820 56.6 8.1 111 -23 20

Polymerization conditions: ethylaluminum dichloride as initiator system, polymerization temperature +40 ° C

the content of al-olefins (C4 ... C16) applies only to the olefins in raffinate II 25

Claims (21)

20 93369 A process for producing synthetic oils, which process comprises 5. polymerizing olefinic hydrocarbons to form an oil product having a high viscosity index and a low pour point, characterized in that - higher linear 10 alpha-olefins containing 6 to 24 carbon atoms are reacted with a hydrocarbon mixture containing substantial amounts of 1-butene and 2-butenes in the presence of an initiator system to form a copolymer-containing reaction product, and - the copolymer is separated from the reaction mixture. 15 Process according to Claim 1, characterized in that the higher linear alpha-olefins are reacted with a hydrocarbon composition containing 15 to 80% by weight of 1-butene, 5 to 50% by weight of 2-butenes. and up to about 10% by weight of isobutene. Process according to Claim 2, characterized in that the higher linear alpha-olefins are reacted with a hydrocarbon composition containing from about 25 to 70% by weight, in particular from 30 to 60% by weight, of 1-butene, and ... 40% by weight, in particular 15-30% by weight of 2-butenes. Process according to Claim 1, characterized in that the hydrocarbon mixture comprises a residue of the C4 fraction which remains after the removal of substantially all the 1,3-butadiene and isobutene compounds. Process according to Claim 4, characterized in that a hydrocarbon mixture is used which comprises a hydrocarbon mixture known as raffinate II obtained from a process for the preparation of methyl tert-butyl ether or polyisobutene * <(an · m »; 93369 21 . Process according to Claim 1, characterized in that 1 to 99% by weight, preferably 5 to 90% by weight and particularly preferably 10 to 70% by weight of higher linear alpha-olefins are added to the hydrocarbon mixture. , which are reacted with the 1-butene and 2-butene fractions, the amount of linear alpha-olefins added being calculated from the total amount of olefins contained after the addition of the mixture. Process according to Claim 1, characterized in that the higher linear alpha-olefins are higher alpha-olefins having from 6 to 18 carbon atoms. 15 Process according to Claim 7, characterized in that 1-octene, 1-decene, 1-dodecene, 1-tetradecene and / or 1-hexadecene are used as the higher linear alpha-olefins. 20 Process according to Claim 1, characterized in that the initiator system used is AlCl 3 in combination with HCl, AlCl 3 in ethyl chloride solution, a liquid complex of AlCl 3, an aromatic solvent and hydrogen chloride, or alkyl aluminum of the general formulas R 1 AlCl or RA 1 Cl 2, R represents lower alkyl having 1 to 6 carbon atoms, together with an anhydrous hydrogen halide. Process according to Claim 9, characterized in that the initiator system is gradually added during the reaction. II. Process according to Claim 9, in which AlCl 3 in ethyl solution or a liquid complex of AlCl 3, toluene and HCl is used as the initiator system, characterized in that alpha-olefins having 6 to 18 carbon atoms 22 93369 are reacted with a hydrocarbon mixture containing at least 30% by weight of 1-butenes, wherein the molar ratio of alpha-olefins to 1-butenes is 1: 1 to 1: 5, to form petroleum products having a viscosity index of 100 to 155 and pour points are +5 ° C ...- 65 ° C. Process according to Claim 11, characterized in that petroleum products with a molecular weight of 400 to 1000 are prepared. Process according to Claim 9, in which alkylaluminum chloride is used as initiator system in combination with anhydrous hydrogen chloride, characterized in that the alpha-olefins having 15 to 16 carbon atoms are reacted with a hydrocarbon mixture containing at least 30% by weight of 1-butene, wherein the molar ratio of alpha-olefins to 1-butene is 1: 1 to 1: 5 to form petroleum products having viscosity indices of 100 to 140 and pour points of 0 ° C to -65 ° C. Process according to Claim 13, characterized in that petroleum products with a molecular weight of 350 to 900 are prepared. 25 Process according to Claim 1, characterized in that the methanol content of the hydrocarbon composition is less than 3000 ppm. Process according to Claim 1, characterized in that the higher linear alpha-olefins are reacted with a hydrocarbon mixture of 1-butene and 2-butenes at a temperature of from -10 ° C to + 70 ° C. 17. An olefinic copolymer useful as a synthetic oil or part thereof, characterized in that it comprises n-butene, cis- and trans-2-butenes and higher linear alpha-olefins having 6 to 18 93369 23 carbon atoms. repeating units and has a number average molecular weight of 300 to 1200 and a molecular weight distribution expressed as Mw / Mn of less than 1.4. 5 Copolymer according to Claim 17, characterized in that the higher linear alpha-olefin units consist of alpha-olefins having from 10 to 16 carbon atoms in the molecule. 10 Copolymer according to Claim 17 or 18, characterized in that the molar ratio of higher linear alpha-olefin units to 1-butene units is 1: 1. . .1: 5. 15 20. A process for the preparation of a useful copolymer product as a synthetic oil or part thereof, characterized in that - higher linear alpha-olefins having from 6 to 18 carbon atoms are mixed with a mixture of C4 hydrocarbons from the production of methyl tert-butyl ether or isobutene selective polymerization and containing at least 15% by weight of 1-butene and at least 5% by weight of 2-butenes to form a reaction mixture, - an initiator system is added to the reaction mixture, - the temperature of the reaction mixture is maintained at -10 to + 70 ° C: - higher linear alpha-olefins are reacted with 1-butenes and 2-butenes to form reaction product 30, and - volatile components and any initiator residues are separated to form an oily product consisting mainly of copolymers with a number average molecular weight of 300-1200. 35 Process according to Claim 20, characterized in that the initiator system is gradually added during the reaction of the higher linear alpha-olefins and the 1- and 2-butenes. 93369 25