In the petrochemical industry, the alkylation process is mainly used to produce high-octane gasoline blending components. For example, isobutane is alkylated with propylene or butene to obtain alkylated oil, which is the earliest application of the alkylation process. Benzene is alkylated with propylene to produce cumene. It was originally used as a blending agent for gasoline, and now it is the main raw material for the production of phenol and acetone. Now the alkylation process is mainly used to produce a variety of important organic products. For example, benzene is alkylated with ethylene to produce ethylbenzene, and benzene is alkylated with C10～C18 olefins to produce high-carbon alkylbenzene, which is a raw material for synthetic detergents. In addition, methyl cumene obtained by alkylation of toluene with propylene can be oxidized and isomerized to produce m-cresol; toluene can be reacted with ethylene to produce vinyl toluene. M-xylene can be produced by isobutylation of xylene musk. 1,2,4-trimethylbenzene is alkylated with methanol or methyl chloride to produce 1,2,4,5-tetramethylbenzene. The alkylation of phenol with isobutylene can produce tert-butyl phenol, and the alkylation with diisobutylene can produce p-octylphenol.

The alkylation reaction generally has two reaction modes: thermal alkylation and catalytic alkylation. Because thermal alkylation requires a higher temperature, and catalytic alkylation is more advantageous, most of the current alkylation reactions use catalytic methods.

The catalytic alkylation reactor is designed as an axial multi-stage adiabatic fixed bed reactor, which is a liquid phase alkylation reaction. It is generally designed to consist of 8 sections of coaxial fixed beds in series. The pipe-type distributor is arranged between the beds to ensure that the material flows evenly between the beds. Inert ceramic balls are set up and down the catalyst bed. A heat exchanger is installed outside the sections to remove the reaction heat.

In this design, the reactor bed lamination is reduced, which can effectively save energy and reduce consumption. The design of the distributor is reasonable, so that the reaction materials are fully mixed, which is conducive to the high efficiency of the reaction. The merits of the appeal have also been verified in actual use. Received unanimous praise from users.

Schematic diagram of the reactor:

DCS interface

Industrial performance

250,000 tons of ethylbenzene/styrene plant of Xinyang Technology Group

Changzhou Xinri Chemical's 250,000-ton Ethylbenzene/Styrene Plant

Shandong Yuhuang Chemical's 200,000-ton ethylbenzene/styrene plant