The catalyst for the hydrogenation of acetylene to ethane-ethylene fraction

 

(57) Abstract:

The invention relates to gas-phase purification of ethane-ethylene fraction of pyrogas from acetylene impurities, in particular to the purification catalysts by the method of selective hydrogenation. The catalyst is an alumina base coated with palladium and modifying additive - cesium in the following ratio, wt.%: palladium 0,01 - 0,5, cesium 0,01 - 0,5-aluminum oxide - rest. Technical result - increase the selectivity of the process. table 1.

The invention relates to gas-phase purification of ethane-ethylene fraction of pyrogas from acetylene impurities, in particular to the purification catalysts by the method of selective hydrogenation.

A known catalyst for the selective hydrogenation of acetylene to ethane-ethylene fraction, comprising: from 0.005 to 0.05 wt.% palladium on aluminium oxide and 0.5 to 1.0 wt. % barium oxide as modifying additives [SU 871377, 1992 , B 01 23/44]. This catalyst at a temperature of 70oC, space velocity of the gas mixture 3000-9000 h-1acetylene contained in a quantity of 0.8 vol.% hereroense completely. Disadvantages are low mechanical strength, short service life and education at the Institute of economy and management of the proposed catalyst is a catalyst for the selective hydrogenation of acetylene to ethane-ethylene fraction, containing alumina base coated with palladium and modifier - chromium, and the components are contained in the following amounts, by weight. %: palladium of 0.001 to 5.0, preferably from 0.01 to 0.5), the chrome of 0.001 to 5.0, preferably from 0.01 to 0.5), -alumina rest [US 4551443 A, 1985, B 01 23/44]. In the process of hydrogenation of acetylene to ethane-ethylene fraction of this catalyst provides selectivity 70-75% at flow rate of the gas mixture 50-10000 h-1the pressure of 3.4-34 MPa and a temperature of 50-200oC. Its disadvantages are low selectivity, the content of toxic element chromium in the catalyst, as modifying additives, high temperature hydrogenation, which leads to the formation of "green oil" on the catalyst surface due to the polymerization reaction of acetylene and ethylene on the active centers of the surface.

The objective of this invention is to provide such a palladium catalyst on a carrier for the purification of ethylene from acetylene by the method of selective hydrogenation, which has a high selectivity reduces the temperature of the hydrogenation, therefore, preventing the formation of "green oil" and do not contain toxic elements.

The proposed catalyst is different from the known fact that as modifying additives it contains cesium in the following ratio, wt.%: palladium 0,01-0,5, cesium 0,01-0,5-aluminum oxide - rest.

The catalyst has the following advantages over the known catalyst, which consists in carrying out the process of hydrogenation of acetylene at lower temperatures of 40-70oC against 50-200oC, which reduces the formation of green oil, used as a modifier of cesium carbonate instead of toxic chromium nitrate. In addition, the proposed catalyst has higher than the known selectivity.

The catalyst is prepared as follows. The addition of palladium chloride dissolved in slobodkina demineralized water, then to the resulting solution was poured an aqueous solution of polyethylene oxide. The resulting solution of palladium chloride and polyethylene oxide dissolved sample Cs2CO3hereinafter this solution is impregnated with dry media-Al2O3with a specific surface area of 0.5-1 m2/H. Impregnated carrier is dried on a water bath for 1-2 hours, then the use is illustrated by the following examples.

Example 1.

A portion of 1.26 g of PdCl2dissolve in 100 ml slobodkina demineralized water, and then to the resulting solution of palladium chloride is poured 100 ml of a 0.002% solution of polyethylene oxide, the resulting solution was thoroughly mixed, and then in a solution dissolving a portion of 1.95 g Cs2CO3and poured 20 ml of demineralized water. The resulting solution of palladium chloride, cesium carbonate and polyethylene oxide impregnated 800 cm3dry media-Al2O3. Then the impregnated carrier is dried on a water bath for 2 h, annealed 5 hours at 150oC. Process EAF at 40oC.

Get the catalyst composition, wt.%: palladium 0,1, cesium 0.1, the rest is aluminum oxide.

Example 2.

The catalyst is prepared analogously to example 1, except that in the impregnating solution add 0,200 g Cs2CO3.

Get the catalyst composition, wt.%: palladium 0,1, cesium 0,01-aluminum oxide - rest.

Example 3.

The catalyst is prepared analogously to example 1, except that in the impregnating solution is added 10 g Cs2CO3.

Get the catalyst composition, wt.%: palladium 0,1, cesium 0,5-aluminum oxide - rest.

R is in the table.

The test catalysts were performed in a pilot reactor flow type. The reactor was loaded 800 cm2sample catalyst. The system gave the source gas mixture of ethane-ethylene fraction and hydrogen composition, vol.%: C2H20,3; C2H455; CH2H640; CH40,4; H20,88; C3H6and C3H8the rest of it.

Every four hours, samples were taken for analysis of the contact strip on the content of the acetylene. Analysis was performed on the chromatograph Color-102" with a flame ionization detector activated coal 0,2-0,4 mm

The reactor pressure was 3.4 MPa, the temperature was varied in the range of 40-70oC, the volumetric rate of gas supply - 1500-3750 h-1.

The results of the tests of the catalysts showed that the selective hydrogenation of acetylene in EAF on the proposed catalyst is higher than the catalyst according to [2], 78-83% vs. 70-75%, under the same conditions process temperature process for the proposed catalyst is lower than for the catalyst according to [2], i.e. 40-70oC against 50-200oC. the catalyst was not observed the formation of "green oil".

Sources of information

1. A. c. USSR N 871377, publ the project of acetylene to ethane-ethylene fraction, containing palladium and modifying additive on the alumina carrier, characterized in that as modifying additives it contains cesium in the following ratio, wt.%:

Palladium - 0,01 - 0,5

Cesium - 0,01 - 0,5

-Aluminum oxide - Rest

 

Same patents:

The invention relates to the chemical industry, and more particularly to a catalytically active materials, compositions, and can be used as a catalyst in producing ammonia by reacting nitrogen with hydrogen

The invention relates to the production of catalysts and can be used in purification processes of hydrocarbon fractions from acetylene and/or diene hydrocarbons and positional isomerization of olefins

The invention relates to a method for preparing a catalyst for reduction of nitrogen oxides in the gas emissions of certain industrial facilities, power plants, compressor stations, gas processing plants, etc

The invention relates to catalysts for production of hydrocarbons, in particular catalyst type hydrotalcite for obtaining aromatic hydrocarbons

The invention relates to organic chemistry, and in particular to methods hydrogenation of acetylene alcohols, which is an intermediate organic compounds used in the pharmaceutical and perfume industry, with high yield and high the speed
The invention relates to the production of catalysts, in particular to a method for the catalytic hydrogenation of benzene and alkylaromatic hydrocarbons in the raw mixes with the mixture of sulfur-containing compounds that can be used in the petrochemical industry, for example in processes of dearomatization diesel fuel

The invention relates to techniques for protecting the environment and can be used for purification of exhaust gases

The invention relates to the production of catalysts and, in particular, to obtain palladium and palladium/gold catalyst for the synthesis of vinyl acetate from ethylene, acetic acid and oxygen-containing gas, and to a method for producing vinyl acetate

The invention relates to petrochemical synthesis and can be used in the preparation of catalysts for selective hydrogenation of acetylene and diene compounds

The invention relates to organic chemistry, namely the method of obtaining the ethyl ester of 10-(2,3,4-trimetoksi-6-were) decanoas acid - intermediate, suitable for the synthesis of idebenone - drug nootropic action

The invention relates to a method of pre-processing of gold-palladium catalyst used in the synthesis of vinyl acetate

The invention relates to methods for heterogeneous catalysts, in particular catalysts for purification of exhaust gases

The invention relates to the field of selective hydrogenation of unsaturated compounds, in particular to a catalyst and method of selective hydrogenation of unsaturated compounds and to a method for producing the catalyst
The invention relates to a process for the preparation of catalysts based on Nickel, stabilized active alumina, for redox processes and can be used in the fine purification of process gases from oxides of carbon, oxygen, and to obtain protective atmospheres by dissociation of ammonia

The invention relates to the production of catalysts for conversion of hydrocarbons

The invention relates to the refining and petrochemical industries, and in particular to methods of preparation of the catalyst for hydrofining of crude oil

The invention relates to the field of technical chemistry, and in particular to methods of cooking media (systems-precursors for catalysts that can be used in almost any heterogeneous catalytic processes in the chemical industry and in the energy sector, such as catalytic oxidation (full and partial), hydrogenation (including the Fischer-Tropsch synthesis), the conversion of hydrocarbons and other

The invention relates to a catalyst for purification of gases from nitrogen oxides mainly in the presence of methane and oxygen, the conversion of natural gas and the method of its production
Up!