Method and device for continuously preparing pivaloyl chloride

Abstract

The invention relates to a method and a device for continuously preparing pivaloyl chloride. The specific operation method comprises the following steps: adding raw materials pivalic acid and phosphorus trichloride to a raw material mixer respectively, uniformly stirring the raw materials, and then conveying the raw materials into a microchannel reactor with a solid catalyst to prepare a chlorination solution; feeding the prepared chlorination solution into two chromatography tanks for chromatography respectively to prepare a crude product of pivaloyl chloride; finally, feeding the crude product of pivaloyl chloride into a rectification section to obtain a pure product of pivaloyl chloride. The microchannel reactor is adopted to replace an original chlorination reactor, so that the reaction is more thorough, the conversion rate is high, and purity is high; a continuous reaction is adopted to replace the original intermittent reaction, and reaction time is greatly shortened to 0.5 hoursfrom 12 hours in the prior art.

Description

technical field [0001] The present invention relates to a kind of method for preparing pivaloyl chloride and equipment thereof, more specifically, relate to a kind of method for continuously preparing pivaloyl chloride and equipment thereof. Background technique [0002] Pivaloyl chloride, also known as trimethylacetyl chloride, is commonly used as a pharmaceutical and pesticide intermediate. It is an intermediate for the production of carbamate insecticide thabicarb and herbicide isoxazolone, and for the synthesis of amides and phenolic ester drugs. It is also widely used in the production of (hydroxy) ampicillin, cephalosporin (hydroxy) ampicillin, cefazolin, dipivaloyl adrenaline and other drugs. [0003] There have been many reports on the preparation process of pivaloyl chloride, and the main industrial production processes are as follows: (1) pivalic acid is prepared from isobutene and carbon monoxide as initial raw materials, and pivaloyl chloride is prepared by react...

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Problems solved by technology

The above-mentioned several pivaloyl chloride preparation techniques are comparatively perfect with the first kind, can make the pivaloyl chloride that meets the standard, but pivaloyl chloride is made by the reaction of pivalic acid and chlorinating agent still has big problem, wherein existing chlorination The reaction devices are all batch reaction devices, which have problems such as low reaction efficiency, long time, high energy consumption, low product conversion rate, and many impurities.

[0004] The existing pivaloyl chloride production processes are all batch-type, adopting the method of tank reaction-separation-rectification purification. After the single-pot reaction, the separation reaction time is long, the operation is complicated, and there are many by-product impurities; in the production process and control of reaction conditions On the one hand, there are technical problems to be solved, and there is no report on the continuous production of pivaloyl chloride

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