The method of oligomerization of lower olefins in a gas-liquid phase
(57) Abstract:The invention relates to methods of producing oligomers of lower olefins during gas-liquid oligomerization of olefins from ethylene, propane, propylene and butane-butylene gas fractions or mixtures thereof and can be used in petrochemistry. Conduct the oligomerization of lower olefins WITH2-C4contained in the gases of various catalytic processes (catalytic cracking, pyrolysis, flare gas) at elevated temperatures and pressures to obtain low molecular weight oligomers used as antiknock additives in motor fuel, in the presence of Nickel(alumino)silicate catalyst containing zeolite type pentasil, faujasite at the following content, wt. %: NiO 10-80, Al2ABOUT31-50, SiO210-60, zeolite 1-40, and solvent-solvent is a liquid hydrocarbon WITHnH-2n+2, benzene or its homologues, and their mixtures-reformate, straight-run gasoline. The method is carried out at a temperature of 30-100oC, pressure of 1.0-10 MPa and space velocity of the liquid raw material is 0.5-2 h-1in the case of natural gas, 250-1100 h-1when the volumetric feed rate of the solvent-solvent of 0.5-1.0 h-1. Thus n the functions are not localized overheating on the catalyst surface. 1 C. p. F.-ly, 3 tables. The invention relates to the field of organic chemistry and catalysis, in particular to a method of producing oligomers of lower olefins that can be used as high-octane components of motor fuels, intermediates in obtaining various additives that improve the performance of oils and fuels.Around the world in many refineries and petrochemical plants there is a situation in which gases from catalytic cracking, pyrolysis, thermal cracking is used as fuel gas, as the plants are not known economically feasible methods of their processing.At the present time for processing olefin-containing gases, only cleaned of impurities: sulfur-containing compounds, acetylene and diene hydrocarbons and water.Known methods of oligomerization of lower olefins processes Polinate and Demersal (oil Refining industry in the U.S. and the former USSR /C. M. Kapustin, S. G. Kukes, R., Bertolacini. - M. : Chemistry, 1995. - 304 S. ).The process of Polinate is designed for processing of light unsaturated hydrocarbons in the gasoline and kerosene fractions on a solid ka is the source of raw materials. The reaction temperature does not exceed 200oWith the pressure in the reactor is 6 MPa. The disadvantage of this process are high demands on the purification of raw materials from sulfur-containing compounds, acetylene and diene in/in, as well as water.The catalyst of the process Dimersol represents soluble in hydrocarbons and ORGANOMETALLIC compound. The disadvantage of this process is nereguliruemost homogeneous catalyst and, as a consequence, the presence of an additional unit of neutralization of the catalyst.Closest to the present invention is a process for the oligomerization of olefinic hydrocarbons (U.S. Pat 4835331). The process is carried out with the use of a catalyst obtained by impregnation of a spherical aluminum oxide with a solution of Nickel nitrate in the presence of dilute nitric acid. As a promoter catalysts additives IVa metals group. The reaction is carried out at 40-110oWith the pressure of 1.4 MPa, adding to the raw material of 0.1 mol. % hydrogen. The raw material used is a mixture of 28.8% n-butane and 71.2% n-butenes containing 27 ppm wt. sulfur in the form of dimethyl sulfide.The disadvantage of this process is the high sensitivity of the catalyst to serosoderjaschei is possible only in the presence of hydrogen, while its content in the raw material mixture should not exceed 0,1 mol. %. At higher hydrogen concentration in the feedstock is significantly reduced selectivity of the oligomerization (intensively flows hydrogenation of olefins).The objective is achieved by oligomerization of lower olefins, C2-C4contained in the gases of various catalytic processes, including catalytic cracking, pyrolysis at elevated temperatures and pressures in the presence of a catalyst. The process is carried out on the Nickel(alumino)silicate catalyst containing zeolite type pentasil, faujasite at the following content, wt. %:
NiO - 10-80
Zeolite - 1-40
and solvent-solvent is a liquid hydrocarbon WITHnH2n+2, benzene or its homologues, and their mixtures - reformate, straight-run gasoline at a temperature of 30-100oC, a pressure of 0.8 to 10 MPa and space velocity of the liquid raw material is 0.5-2 h-1in the case of natural gas, 250-1100 h-1when the volumetric feed rate of the solvent-solvent for 0.5-2 h-1. When this lower olefins can contain up to 2.6 wt. % of hydrogen sulfide and up to 5.3 wt. % hydrogen.Low-molecular Oli is CLASS="ptx2">Use in the oligomerization solvent-solvent can effectively remove the heat of reaction, preventing hot spots on the catalyst surface, preventing the leakage of unwanted processes of hydrogenation of the olefinic/and poisoning of the catalyst containing sulfur compounds (hydrogen sulfide).The invention is illustrated in the following examples 1-34:
Example 1. 718 g of aluminosilicate gel (the content of SiO2to 18.6 wt. %, Al2O3- 1.4 wt. %, the rest is H2O) were placed in a flask with stirrer and rushed 670 ml of distilled water. Under stirring was added 240 g of Nickel nitrate dissolved in 320 ml of distilled water. To the mixture was added concentrated ammonia solution to pH 9. The suspension was heated to 90oWith and endured 3 hours with continuous stirring, then filtered, washed with distilled water. Carefully blended 230 g of the obtained Nickel-silicate, 38 g of aluminum hydroxide (pseudoboehmite - P. PP - 70 wt. %) and 7 g of zeolite NCVM (domestic analogue of ZSM-5, P. p. P. - 5 wt. %). The mass was evaporated to formemost, sformovat into pellets, dried at 120oC for 5 hours, probalily at a temperature of 350oWith iO2- 33,1%, zeolite-DCM - 10.0% of (R N1).Example 2. 120 g of ground silica gel (grain size 0.5 mm) were placed in a flask with stirrer and added with stirring a solution of 480 g of Nickel nitrate in 640 ml of distilled water. Then brought the pH value of the suspension to 9.0, Prilepa 25% ammonia solution (0.5 l) was heated to 90oWith and kept under stirring for 3 hours. Next was filtered and washed precipitate with distilled water. The precipitate (Nickel-silicate) are thoroughly mixed with calculated amounts of zeolite type CVM and aluminum hydroxide by adding 100 ml of water for better mixing, brought the pH value of the suspension to 5.0, Prilepa concentrated nitric acid, and evaporated to formulate. He sformovat into pellets, dried at 120oC for 3 hours, probalily at a temperature of 350oWith 2 hours and at 500oWith 3 hours. The resulting catalyst has the following composition, wt. %: NiO - 36,0, Al2O3- 18,4, SiO2- 35,6, zeolite-DCM - 10,0
Examples 3-34. The catalysts obtained in examples 1,2, experience in the way of oligomerization of olefins WITH2-C4. Registergui gas (containing hydrogen and hydrogen sulfide) and the solvent eluent arrive at the site of mixing, after which the mixture is fed is 30-100oC and a pressure of not less than 8 ATM. The composition of the raw materials used are shown in table 1.Table 2 presents data on the conversion of various feedstocks containing olefins WITH2-C4in the presence of and without solvent eluent. Liquid products obtained during the transformation of the gas fractions accumulate within 6 hours, and then chromatographic determine their composition, analysis of process gases is carried out every hour.Example 35. 83,2 g spherical - Al2ABOUT3according to the technique of the prototype, was soaked in an aqueous solution of 180 g of uranyl nitrate Nickel, and 7.8 g of the pentahydrate of tin chloride and 2.3 g of concentrated nitric acid. The mixture was stirred on a rotary evaporator at room temperature for 1 hour, then raised the temperature and evaporated to dryness for 4 hours. Before the experiment, the catalyst was progulivali for 4 hours at a temperature of 400oC. the resulting catalyst contains NiO - 36,0 wt. %.Examples 36-51. Testing of the catalyst prepared according to example 35, held in the examples 3-34. The results are given in table 3.Comparison of transformation of the same species of the gas indicates that idca oligomers). In addition, the activity of the catalysts proposed in the present invention (examples 1, 2), 10-20% higher than that of the sample prepared according to the prior art (example 35). 1. The method of oligomerization of lower olefins WITH2-C4contained in the gases of various catalytic processes, including catalytic cracking, pyrolysis, flare gases at elevated temperatures and pressures to obtain low molecular weight oligomers used as antiknock additives in motor fuel, in the presence of a catalyst, wherein the process is carried out in the presence of Nickel(alumino)silicate catalyst containing zeolite type pentasil, faujasite at the following content, wt. %: NiO 10-80, Al2ABOUT31-50, SiO210-60, zeolite 1-40, and solvent-solvent is a liquid hydrocarbon WITHnH-2n+2, benzene or its homologues, and their mixtures - reformate, straight-run gasoline at a temperature of 30-100oC, pressure of 1.0-10 MPa and space velocity of the liquid raw material is 0.5-2 h-1in the case of natural gas, 250-1100 h-1when the volumetric feed rate of the solvent-solvent for 0.5-2 h-1.2. The method according to p. 1, characterized in that the lower olefins contain up to 2.6 wt. %
FIELD: petrochemical processes.
SUBSTANCE: feedstock olefins are submitted to oligomerization in contact with zeolite oligomerization catalyst and C4-hydrocarbons isolated from resulting products are then aromatized on zeolite aromatization catalyst. Hydrogen-containing dry gas recovered from aromatization products is used for oligomerization-preceding selective hydrogenation of butadiene in feedstock to give butylene-enriched starting material.
EFFECT: prolonged catalyst lifetime.
3 cl, 3 tbl
FIELD: petrochemical processes.
SUBSTANCE: at least one-step oligomerization (step b) is carried out or this oligomerization is carried out in two steps: limited oligomerization b1 and final oligomerization b3, wherein catalytic oligomerization of olefins having 4 carbon atoms is carried out in presence of other olefins also contained in charge, these other olefins belonging to group consisting, on one hand, of ethylene and, on the other hand, of C5- or C6-olefins to produce oligomers. Further, in step d, at least part of oligomers obtained is subjected to catalytic cracking in reactor differing from oligomerization reactor to produce, in particular, propylene. Process also allows fixed-, moving-, and fluidized-bed cracking to be performed and additional oligomers to be possibly obtained.
EFFECT: optimized yield, conversion, and propylene selectivity.
19 cl, 2 dwg, 5 tbl, 3 ex
FIELD: industrial organic synthesis.
SUBSTANCE: linear alpha-methylstyrene dimers that can be used as molecular weight regulators for various polymers, as varnish solvents, and as base material in production of synthetic oils are obtained via oligomerization of α-methylstyrene in presence of zeolite ZSM-12 in H form in amount 1 to 10% at temperature 60-120°C.
EFFECT: increased selectivity and simplified production process.
1 tbl, 8 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for synthesis of linear unsaturated dimmers of α-methylstyrene that are used as modifying agents in manufacturing polymers. Method is carried out by the dimerization reaction in the presence of zeolite Y at the mole ratio SiO2/Al2O3 = 6.2-7.0 in NaH-form and ionic exchange degree 40-60%. The amount of catalyst is 1-5 wt.-%, the reaction temperature is 40-800C. Invention provides increasing working time of catalyst and improving indices of the process.
EFFECT: improved method of synthesis.