Pre-hydrogenation method of trace acetylene in methanol to olefins unit

Abstract

The invention relates to a pre-hydrogenation method of trace acetylene in a methanol-to-olefins device. The adiabatic bed reactor used for hydrogenation is located before the demethanizer or deethanizer, and is characterized in that: the fixed bed reactor is equipped with Pd ‑Cu series catalyst, the catalyst is combined with the bipyridine derivative with hydroxyl by the carrier during the preparation process, and the hydroxy bipyridine derivative combined with the carrier forms a metal complex with the active component; the hydrogenation method of the present invention is adopted , the selectivity of the hydrogenation reaction is much better than the traditional hydrogenation method, and the loss of ethylene is reduced; the hydrogenation activity is excellent, the content of acetylene at the outlet is significantly lower than the other two hydrogenation methods, and the purity of ethylene is improved, so that the polymerization grade ethylene can be improved. The performance of the product and the reduction of green oil make the active center of the catalyst not covered by by-products, the activity and selectivity of the catalyst are well maintained, and the service life of the catalyst is prolonged.

Description

technical field [0001] The invention relates to a selective hydrogenation method, in particular to a method for pre-hydrogenation of trace acetylene in a methanol-to-olefins device. Background technique [0002] Low-carbon olefins such as ethylene and propylene are important basic chemical raw materials. With the development of my country's national economy, especially the development of modern chemical industry, the demand for low-carbon olefins is increasing day by day, and the contradiction between supply and demand will become increasingly prominent. So far, the important way to produce low-carbon olefins such as ethylene and propylene is still through catalytic cracking and cracking of naphtha and light diesel oil (both from petroleum). As raw materials for ethylene production, naphtha, light diesel oil, etc. Raw material resources are facing an increasingly serious shortage. In addition, in recent years, my country's crude oil imports have accounted for about half of ...

AI Technical Summary

Problems solved by technology

Using this patented method, the carrier adsorbs a specific polymer compound, and chemically adsorbs the polymer through the hydroxyl group of alumina. The amount of polymer compound adsorbed by the carrier will be limited by the number of hydroxyl groups of alumina; The complexation effect of the catalyst is not strong, and sometimes the loading capacity of the active components does not meet the requirements, and some active components remain in the impregnating solution, resulting in an increase in the cost of the catalyst; the preparation of carbon dioxide hydrogenation catalysts by this method also has the disadvantage of complex process flow

[0034] In the process of selective hydrogenation of trace acetylene with high space velocity, especially in the pre-hydrogenation process with high CO content, the hydrogenation condition requires high catalyst activity, and Pd is used as the active component and Ag is used as the active component. The bimetallic catalyst supported by the auxiliary agent is used in this type of device. The reaction temperature is high, the activity cannot meet the requirements of the device, and it is prone to leakage. It is necessary to select a more suitable auxiliary agent to prepare the catalyst to meet the requirements of the device hydrogen requirement

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