Method for preparing p-xylene by alkylation of benzene and methanol

Abstract

The invention provides a method for preparing p-xylene from benzene and methanol through alkylation on a fixed-bed radial-flow reactor with a multichannel structure. The method mainly overcomes the problems of small raw material treating capacity of a unit catalyst within unit time, inadequate usage of the catalyst, high energy consumption in separation, low production efficiency of reactors and the like in the prior art. According to the invention, the fixed-bed radial-flow reactor is employed, and a separation process of separation at first and condensation next is beneficial for reduction of energy consumption; and the process of recovering a part of water produced in reaction is beneficial for heat removal of catalyst beds and inhibition of carbon formation of the catalyst.

Description

technical field [0001] The invention belongs to the technical field of chemical reaction engineering, and in particular relates to a method for preparing p-xylene by alkylation of benzene and methanol in a fixed-bed radial reactor. Background technique [0002] Benzene is a chemical product with a wide range of uses, mainly from catalytic reforming, coal tar, and ethylene processes. With the vigorous development of the oil refining industry and coal coke industry, there is an excess capacity of benzene in the market, and the development of benzene is more valuable. Access to access becomes imperative. In recent years, there has been a large excess of methanol production capacity in the domestic market, and methanol has become a relatively cheap chemical raw material. Therefore, the mixed xylene produced by the alkylation of benzene and methanol can be used as a raw material for increasing the production of p-xylene in an aromatics complex, which has strong social and econom...

AI Technical Summary

Problems solved by technology

[0009] The present invention describes a method for producing p-xylene by alkylation of benzene and methanol on a fixed-bed radial reactor with a multi-channel structure, and mainly solves the problem of a small amount of raw materials processed per unit time by a unit catalyst in the prior art. Problems such as catalyst underutilization, high energy consumption for separation and low reactor production efficiency

[0010] The present invention aims to solve the problems of low catalyst output per unit time, difficulty in temperature control of catalyst bed hot spots, low utilization rate in the active cycle, etc. in the existing benzene-methanol alkylation fixed bed axial reactor technology, and provides a A New Fixed-Bed Radial Reactor Process for the Alkylation of Benzene and Methanol to Mixed Aromatics

Images