Selective hydrogenation method of trace amount of acetylene in methanol to olefin (MTO) apparatus

Abstract

A selective hydrogenation method of trace amount of acetylene in a methanol to olefin (MTO) apparatus. In the method, a C2 material from the top of a deethanizing column in the MTO apparatus is fed into an adiabatic bed reactor to perform selective hydrogenation. A Pd-Ni-series catalyst is arranged in the adiabatic bed reactor and is prepared with Al2O3 or a mixture of the Al2O3 with other oxides as a carrier. During preparation of the catalyst, the carrier is combined with hydroxylbipyridine, wherein a metal complex is formed from the hydroxyl bipyridine combined on the carrier and active components. The reaction conditions include: inlet temperature of the adiabatic bed reactor is 45-150 DEG C, reaction pressure is 2.0-3.5 MPa and space velocity is 2000-7000 / h. The method, when being used for the selective hydrogenation, improves activity and selectivity of the catalyst significantly and improves the stability of the catalyst. The catalyst has excellent anti-impurity interference capability and is especially used in a trace amount acetylene hydrogenation apparatus being high in impurity content, such as sulfur and arsenic.

Description

technical field [0001] The invention relates to a selective hydrogenation method, in particular to a selective hydrogenation method for trace amounts of acetylene in methanol-to-olefins. 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 hal...

AI Technical Summary

Problems solved by technology

Using this patented method, the carrier adsorbs a specific polymer compound through the chemical adsorption of the hydroxyl group of alumina and the polymer, and the amount of the polymer compound adsorbed by the carrier will be limited by the number of hydroxyl groups of alumina; The cooperation effect is not strong, and sometimes the loading capacity of the active components does not meet the requirements, and some active components remain in the impregnation 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 complicated process

[0030] In the methanol-to-olefins unit, the trace acetylene hydrogenation unit contains certain impurities such as As and S, and the bimetallic supported catalyst with Pd as the active component and Ag as the auxiliary agent is used in this type of unit, As and S Impurities such as impurities affect the activity of the catalyst, and in severe cases can cause catalyst deactivation, thereby bringing the risk of alkyne leakage in the device

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