RU2480512C1 - Method to produce base for synthetic base oils - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the method to produce a base of synthetic base oils, including cooligomerisation of hydrocarbon with α-olegins in presence of a cationic catalytic system, containing aluminium and a cocatalyst, in which the hydrocarbon is ethylene, and aluminium is a highly dispersed powder with particle size within 1 - 100 mcm, and α-olegins are octene-1 and/or decene-1, the process of cooligomerisation is carried out at the temperature of 90-110°C and ethylene pressure of 30-50 bar, at the same time the catalytic system additionally contains an activator in the form of sesquiethylaluminiumchloride (SEAC) or diethylaluminiumchloride (DEAC), and the cocatalyst is isopropylchloride (IPC) at the mole ratio of IPC: A1, equal to 0.3-3.0 and the mole ratio of SEAC (DEAC): A1, being within the limits from 0.02 to 0.07.

EFFECT: high yield of a target product, improved main properties of a produced base of base oils.

1 tbl, 9 ex

Description

The invention relates to a technology for producing the basics of synthetic base oils and can be used in the petrochemical industry.

The most important problem in the development of the process of co-oligomerization of ethylene with α-olefins is the choice of an effective catalytic system. The main task of the catalysts is to ensure the synthesis of co-oligomers of α-olefins with higher α-olefins with a high yield and a certain level of physicochemical properties, the processability of the process as a whole and the subsequent stages to remove catalyst residues from the oligomerizate.

Known methods for producing polyolefin bases of synthetic oils differ among themselves in the compositions of cationic catalysts used in them.

A known method of cationic oligomerization of olefins under the action of a catalytic system comprising aluminum metal and carbon tetrachloride. The catalyst for oligomerization of olefins by this method is obtained by reacting aluminum metal with carbon tetrachloride at temperatures of 40-80 ° C and a mass ratio of aluminum to carbon tetrachloride equal to 1: (20-80) in carbon tetrachloride in the absence of olefins in an inert atmosphere ( RF patent No. 2212935).

The disadvantage of this method is the use of carbon tetrachloride in the composition of the used catalytic system with a high ratio of CCl ₄ / Al (0). This leads to the inclusion in the composition of the products of a large amount (up to 3.0% by weight) of chlorine that is difficult to remove from them. Another disadvantage is the low activity and selectivity of the target product of the Al (0) / CCl ₄ catalyst system used in this method.

A known method of producing the basics of synthetic oils, in which the catalyst system Al (0) -HCl- (CH ₃ ) ₃ CCl is used, in the presence of which oligomerization of higher α-olefins C ₄ -C ₁₄ , mainly C ₁₀ , at temperatures from 110 up to 180 ° C, molar ratios of HCl / Al (0) ranging from 0.002 to 0.06 and molar ratios of RCl / Al (0) ranging from 1.0 to 5.0. When using decene-1, the following oligomerizate characteristics are obtained after hydrogenation: kinematic viscosity at 100 ° C is 3.9 cSt, viscosity index 130, pour point minus 60 ° C, flash point 215-220 ° C (RF Patent No. 2287552).

The disadvantage of this method is the additional introduction in the process of oligomerization of aromatic hydrocarbons (benzene, toluene, naphthalene) and, as a result, their presence in the finished product, which limits the scope of use of the latter.

These known methods for the preparation of synthetic oil bases relate to the process of oligomerization of C ₈ -C ₁₀ olefins in the presence of aluminum-containing catalyst systems.

All methods of this type have two common significant drawbacks. The main common disadvantage of the known methods for the preparation of decene oligomers is the relatively low conversion of the monomer and the selectivity of the process. Another common drawback is the high cost of the product due to the use of expensive decene-1 as a monomer.

Decen-1 belongs to the category of scarce and expensive chemical raw materials. It is obtained only in the processes of ethylene oligomerization under the influence of triethyl aluminum or complex catalysts based on metals (Ti, Zr, Ni, Fe, Pd), which determines the high cost of the synthesized oils.

The closest technical solution to the proposed is a method for producing synthetic base oils based on C ₂₀ -C ₆₀ oligomers of α-olefins, which are mainly used octen-1 and decen-1, in the presence of a two-component catalytic system containing aluminum alkyl halide and an organic halide. As the aluminum alkyl halide, ethyl aluminum sesquichloride or diethyl aluminum chloride is used. The halide compound is tert-butyl chloride, allyl chloride or benzyl chloride. Oligomerization is carried out at temperatures of 100-150 ° C. The yield of oligomeric product is at least 56% vol. (US Patent No. 4041098).

The disadvantage of this method and catalytic systems is the low yield of the target fraction and insufficiently high viscosity indices of the resulting product. The disadvantages of this method also include the instability of the process due to non-isothermal reaction in the presence of this catalytic system, which leads to low conversion of the monomer and the selectivity of the process. The result is a low yield of the target product with an insufficiently high viscosity index.

The technical problem solved by this invention is to increase the selectivity of the process and to ensure the synthesis of co-oligomers of α-olefins with higher α-olefins with a high yield of the target product, an increase in the viscosity index of chemical purity and thermo-oxidative stability, and a decrease in the pour point and volatility of the resulting product.

This technical problem is solved in that the process of co-oligomerization of ethylene with α-olefins is carried out at a temperature of 90-110 ° C and an ethylene pressure of 30-50 bar, while the cationic catalytic system contains aluminum, cocatalyst and an activator in the form of sesquietylaluminium chloride (SEAX) or diethylaluminium chloride ( DEAC), and isopropyl chloride (IPC) is used as a cocatalyst with a molar ratio of IPC: Al equal to 0.3-3.0, and a molar ratio of SEAC (DEAC): Al ranging from 0.02 to 0.07. The aluminum of the catalytic system has the form of a fine powder with particle sizes ranging from 1 to 100 μm, and octene-1 or decen-1 is used as ethylene co-oligomers.

These symptoms are significant. In accordance with this method, in order to increase the selectivity and improve technical and economic indicators, instead of the expensive octene-1 and decene-1, partially, a cheaper and more affordable monomer, ethylene, is used, the content of which in the polymer chain can reach 50% of the mass. The fundamental difference between ethylene-α-olefin oils and poly-α-olefin oils is the replacement in the macromolecular chain of a part of alpha-olefins with ethylene, which, with other advantages, ensures a reduction in production costs. The co-oligomerization of ethylene with α-olefins is provided by the proposed catalytic system that implements this process in the presence of an activator at a given temperature and pressure of ethylene. That is, the technical problem is solved by the claimed combination of features in their combination. The catalytic system is characterized by high efficiency in the synthesis of high-index low-setting synthetic ethylene-α-olefin oils.

The advantage of the process of co-oligomerization of ethylene with α-olefins in comparison with the existing technology for the production of poly-α-olefin oils is the lower cost of energy and raw materials. Saving resources is achieved through the use of a cheaper and more affordable monomer - ethylene, the content of which in the polymer chain can reach 50% of the mass.

The effectiveness of the method was evaluated in the process of co-oligomerization of ethylene with octene-1 and decene-1 by the residual content of α-olefin taken for co-oligomerization, and by the content of the oil fraction boiling above 300 ° C in the reaction mass obtained after the process, washing from the catalyst mass drying and fractionation.

The method is illustrated by the following examples.

Example 1

The process of co-oligomerization of ethylene with octene-1 is carried out at a temperature of 110 ° C and an ethylene pressure of 50 bar. The cationic catalyst system contains aluminum in the form of a finely divided powder with a particle size of 100 μm, an activator in the form of sesquietyl aluminum chloride (SEAX) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 0.3, and a molar ratio of SEAX: Al equal to 0.07 .

Example 2

The process of co-oligomerization of ethylene with octene-1 is carried out at a temperature of 90 ° C and an ethylene pressure of 30 bar. The cationic catalyst system contains aluminum in the form of a finely divided powder with a particle size of 10 μm, an activator in the form of sesquietyl aluminum chloride (SEAX) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 3, and a molar ratio of SEAX: Al equal to 0.02.

Example 3

The process of co-oligomerization of ethylene with octene-1 is carried out at a temperature of 100 ° C and an ethylene pressure of 40 bar. The cationic catalytic system contains aluminum in the form of a fine powder with a particle size of 1 μm, an activator in the form of diethylaluminium chloride (DEAC) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 1, and a molar ratio of DEAC: Al equal to 0.05.

Example 4

The process of co-oligomerization of ethylene with octene-1 is carried out at a temperature of 95 ° C and an ethylene pressure of 50 bar. The cationic catalytic system contains aluminum in the form of a finely divided powder with particle sizes of 50 μm, sesquiethylaluminium chloride (SEAX) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 2, and a molar ratio of SEAX: Al equal to 0.04.

Example 5

The process of co-oligomerization of ethylene with decene-1 is carried out at a temperature of 110 ° C and an ethylene pressure of 50 bar. The cationic catalyst system contains aluminum in the form of a finely divided powder with particle sizes of 80 μm, sesquietylaluminium chloride (SEAX) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 0.3, and a molar ratio of SEAX: Al equal to 0.02.

Example 6

Co-oligomerization of ethylene with decene-1 is carried out at a temperature of 90 ° C and an ethylene pressure of 30 bar. The cationic catalytic system contains aluminum in the form of a finely dispersed powder with a particle size of 10 μm, diethylaluminium chloride (DEAC) and isopropyl chloride (IPC) with a molar ratio of IPC: Al of 3 and a molar ratio of DEAC: Al of 0.07.

Example 7

Co-oligomerization of ethylene with decene-1 is carried out at a temperature of 100 ° C and pressure

ethylene 40 bar. The cationic catalyst system contains aluminum in the form of a finely divided powder with a particle size of 1 μm, sesquietyl aluminum chloride (SEAX) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 1.5, and a molar ratio of SEAX: Al equal to 0.04.

Example 8

Co-oligomerization of ethylene with decene-1 is carried out at a temperature of 105 ° C and an ethylene pressure of 45 bar. The cationic catalytic system contains aluminum in the form of a fine powder with a particle size of 60 μm, diethylaluminium chloride (DEAC) and isopropyl chloride (IPC) with a molar ratio of IPC: Al equal to 2, and a molar ratio of DEAC: Al equal to 0.06.

Example 9 (comparison with the prototype)

Co-oligomerization of ethylene with hexene-1 is carried out in the presence of a catalytic system containing aluminum, alkyl chloride RCl, where R is isopropyl, with a molar ratio of alkyl chloride, aluminum and ethylene of 1: (10) :( 1100) at a temperature of 200 ° C and a pressure of 100 bar.

The main physicochemical properties of the target fraction of ethylene co-oligomers with α-olefins obtained in the process of co-oligomerization of ethylene with octene-1, decen-1 and hexene-1 are shown in table 1 for examples 1-9.

Table

Example Source α-olefin The conversion of α-olefin,% The yield of the target fraction,% vol. Kinematic viscosity, mm ² / s Viscosity index Pour point, ° C 40 ° C 100 ° C one Octen-1 99.5 90.0 19.24 4,230 130 Below minus 60 2 Octen-1 99.3 83.0 14.12 3,368 131 Below minus 60 3 Octen-1 99.0 83.5 13.16 3,402 142 Below minus 60 four Octen-1 98.8 82.7 11.69 3,160 148 Below minus 60 5 Decen-1 99.8 85,2 17.46 4,044 137 Below minus 60 6 Decen-1 99.6 82.5 16.23 3,865 147 Below minus 60 7 Decen-1 99.3 82,4 15.10 3,555 128 Below minus 60 8 Decen-1 99.1 83.1 12.8 3,987 140 Below minus 60 9 Hexene 1 95.2 90.0 16.00 3,550 109 Minus 58

As can be seen from the table, the claimed method provides an increase in the basic physical and chemical properties of the obtained base of base oils, significantly exceeding those of the prototype.

The products obtained by this technology are characterized by a high viscosity index (120-150), high chemical purity, low pour point (minus 60 ° C and below), low volatility, high thermo-oxidative stability and are the basis for the production of hydraulic, aviation oils, motor and transmission oils of northern and arctic brands. Due to the absence of aromatic hydrocarbons, they can be used as medical, perfume and vaccine oils.

Claims (1)

A method of obtaining a base of synthetic base oils, including the co-oligomerization of a hydrocarbon with α-olefins in the presence of a cationic catalyst system containing aluminum and cocatalyst, characterized in that ethylene is used as the hydrocarbon, and aluminum has the form of a highly dispersed powder with particle sizes ranging from 1 to 100 μm, octene-1 and / or decen-1 are used as α-olefins, the process of co-oligomerization is carried out at a temperature of 90-110 ° C and an ethylene pressure of 30-50 bar, while the catalyst system additionally contains an activator in the form of sesquietyl aluminum chloride (SEAX) or diethyl aluminum chloride (DEAX), and isopropyl chloride (IPC) is used as a cocatalyst with a molar ratio of IPC: Al of 0.3-3.0 and a molar ratio of SEAX (DEAC): Al in ranges from 0.02 to 0.07.