Preparation method for sec-butyl acetate with product separating and reclaiming technique

Abstract

The invention relates to a process for preparing sec-butyl acetate, with product separation and reclamation technology, which is characterized in that the reaction is processed in one catalysis distillation column composed of a column reactor, an exhausting section, a reaction section, a distillation section, and a column top reflux condenser, wherein the reaction section is filled with catalyst,acetic acid and mixture C4 or butene which are reversely contacted and reacted on the surface of catalyst, the non-reacted mixture C4 or butene is evaporated out from the top of the catalyst distillation column, the product mixture is fed into an azeotropic distillation column, added with an entrainer a which can form azeotropic material with sec-butyl acetate, the distillate at the top of the azeotropic distillation column is fed into a treating column, to be distilled to obtain sec-butyl acetate, and the fraction at the lower portion of the azeotropic distillation column, is fed into an acidconcentrating tower, added with an entrainer b which can form azeotropic material with the entrainer a, to process azeotropic distillation to be circulated and feedback to the reaction system. The invention has the advantages of simplified separation, low cost, low energy consumption, high material utilization and the like.

Description

technical field [0001] The invention relates to a method for preparing sec-butyl acetate, in particular to a method for preparing sec-butyl acetate with a product separation and recovery process. Background technique [0002] Currently, using acetic acid and mixing C 4 (or butene) as raw material, the method for preparing sec-butyl acetate usually obtains by carrying out esterification in a tubular fixed-bed reactor. Compared with the traditional process, by mixing C 4 (or butene) as a raw material, utilizing it to react with acetic acid to prepare sec-butyl acetate has the advantages of wide source of raw material and low cost, good economic benefit, and environmental friendliness. U.S. Patent No. 5,457,228 discloses a method for preparing sec-butyl acetate, which is to mix reaction material acetic acid with C 4 (or butene) is introduced from the upper part of the tubular fixed bed reactor, including unreacted mixed C 4 (or butene), unreacted acetic acid and the product...

AI Technical Summary

Problems solved by technology

The deficiency of this method is: (1) adopt shell-and-tube fixed bed to make reactor, send that part product mixture of separation generally need to pass through flash tower first, unreacted mixed C 4 (or butene) is removed from the product mixture, thus increasing the difficulty of the subsequent product separation process; and the temperature and pressure of the flash tower are high, and the energy consumption is high; (2) the reaction material is circulated into the reactor to make the olefin The polymerization tendency increases, which affects product purification; (3) the use of circulating pumps and heat exchangers increases energy consumption

The separation process disclosed in this Chinese patent application is only suitable for product separation using a tubular fixed-bed reactor, and the process is relatively complicated and consumes a lot of energy

[0004] And in the prior art of preparing sec-butyl acetate, the method and the technique that product preparation, product separation, product recycling are integrated have not been reported yet

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