Selective hydrogenation method for C2 fraction

Abstract

The invention relates to a selective hydrogenation method for a C2 fraction, is used for post-hydrogenation, and introduces C2<+> materials from a front dethanizer in an ethylene device to a fixed bed reactor for selective hydrogenation after pressure hydrogen distribution. The selective hydrogenation method is characterized in that: the fixed bed reactor is provided with a Pd-Ag catalyst, Al2O3 or a mixture of Al2O3 and other oxides is used as a carrier, and the catalyst forms an organic polymer metal complex during preparation process; and the reaction conditions are as follows: the inlet temperature of the fixed bed reactor is 40-100 DEG C, the reaction pressure is 1.5-2.5 MPa and the gas space velocity is 2000-10000 h<-1>. The selective hydrogenation method provided by the invention has higher hydrogenation reaction activity and selectivity than traditional hydrogenation methods, and the generation amount of green oil during hydrogenation process greatly decreases, thus maintaining good activity and selectivity of the catalyst.

Description

technical field [0001] The invention relates to a method for selective hydrogenation, in particular to a method for selective hydrogenation of carbon distillates to remove acetylene. Background technique [0002] The production of polymer grade ethylene is the leader of the petrochemical industry, and polymer grade ethylene and propylene are the most basic raw materials for downstream polymerization units. Among them, the selective hydrogenation of acetylene has an extremely important impact on the ethylene processing industry. In addition to ensuring that the acetylene content at the outlet of the hydrogenation reactor reaches the standard, the selectivity of the catalyst is excellent, which can make ethylene generate as little ethane as possible, which is beneficial to improving the entire process. It is of great significance to improve the ethylene yield of the process and improve the economic benefits of the device. [0003] The cracked carbon distillate contains acetyl...

AI Technical Summary

Problems solved by technology

When the co-impregnation method is used, due to the different interactions between the precursors of the two metal ions and the carrier, as well as the surface tension and solvation, it is difficult to form a uniform loading of the two components, and only a partial alloy structure can be formed.

When this catalyst is used in the selective hydrogenation of carbon distillates, the selectivity is often better at the initial stage of the reaction, and the selectivity continues to decline with the extension of the operating time. Generally, it needs to be regenerated after 3 to 6 months of operation, and the economic loss is relatively large.

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