Stearoyl chloride phosgene synthesis method

Abstract

The invention provides a stearoyl chloride phosgene synthesis method. The method comprises the steps of 1, heating stearic acid; 2, heating the catalyst DMF; 3, introducing phosgene into a first-order reaction chamber continuously; 4, spraying heated stearic acid downwards through a spraying device, and spraying the heated catalyst DMF downwards through the spraying device at the same time; 5, introducing gas which does not react completely into a second-order reaction chamber; 6, introducing gas which does not react completely into a third-order reaction chamber; 7, introducing gas into a tail gas processing device; 8, rectifying materials obtained after reaction is conducted in the first-order reaction chamber, the second-order reaction chamber and the third-order reaction chamber, so that a finished product is obtained. By the adoption of the production technology, the contact area of reactants can be increased, reaction time can be shortened, increase of by-products can be avoided, and therefore reaction efficiency is improved, cost is reduced, and phosgene waste is reduced.

Description

technical field [0001] The invention relates to the field of plastic fine chemical production, in particular to a phosgene synthesis method of stearoyl chloride. Background technique [0002] Stearoyl chloride (Stearoylacidchloride, also known as octadecanoyl chloride) is a pesticide intermediate, and also a raw material for the production of neutral sizing agent for papermaking - alkyl ketene dimer (AKD). Under the catalysis of dimethylformamide (DMF), it reacts with phosgene to generate acylated products. The reaction is mainly divided into two stages: [0003] 1. Catalyst activation stage [0004] Phosgene reacts with dimethylformamide to generate active group (1), which is very unstable and releases a molecule of CO very quickly. 2 , and generate an active group (2); [0005] 2. The active group (2) reacts with stearic acid to generate stearyl chloride, regenerates dimethylformamide, and releases a molecule of HCl at the same time; [0006] The reaction is an exothe...

AI Technical Summary

Problems solved by technology

A large amount of waste gas is generated during the reaction process, and the unreacted phosgene in the system will be carried out with the waste gas. In the existing relatively mature industrial production, enamel stirring reactors are generally used, the stirring speed is slow, and the mass transfer intensity is not high. The reaction speed is slow, the reaction cycle is as long as more than 12 hours, and intermittent production is adopted, the excess ratio of phosgene is high, the waste of phosgene is serious, and the reaction cost is high