Method for recycling dichloromethane in acesulfame potassium synthesis process

Abstract

The invention discloses a method for recycling dichloromethane in an acesulfame potassium synthesis process. The method comprises the steps of a, adding roughly distilled dichloromethane into a dehydrating tower, heating, condensing to enable steam of a mixed solution of dichloromethane and water to enter a dehydration overflow tank and dichloromethane containing qualified water at the bottom to enter a semi-finished product tank so as to be used by a rectifying tower; b, enabling dichloromethane containing unqualified water at the bottom of the overflow tank to enter the dehydrating tower again through backflow and dichloromethane with high water content at the top to enter a crude product tank, and regularly discharging layered water in the crude product tank; c, enabling dichloromethane containing qualified water in the semi-finished product tank to enter the rectifying tower, distilling to 45 DEG C, enabling dichloromethane steam to enter the dehydration overflow tank, and sucking dichloromethane with high impurity content at the bottom into a residual solution tank; and d, after detecting dichloromethane in the dehydration overflow tank to be qualified, placing dichloromethane into a finished product tank so as to be used for synthesizing and sulfonating, and enabling the unqualified dichloromethane to enter the rectifying tower so as to be rectified again.

Description

technical field [0001] The invention relates to a method for recovering dichloromethane in the synthesis process of acesulfame potassium. Background technique [0002] The dichloromethane recovery route in the traditional acesulfame-K synthesis process is as follows: figure 1 As shown, dichloromethane should first be passed through crude distillation, then transferred to the impurity removal tank, add sulfur trioxide to remove impurities, and then transfer to the neutralization tank, pass ammonia gas for neutralization, and after neutralization, use steam to heat to obtain the finished product Dichloromethane: The recovery process is complicated, the process reaction time is long, the production capacity is low, and the production cost is high, which does not conform to the national industrial policy. [0003] The proposal of a new production process for acesulfame potassium dichloromethane double-tower recovery completely solves the above problems. Continuous operation sh...

AI Technical Summary

Problems solved by technology

[0002] The dichloromethane recovery route in the traditional acesulfame-K synthesis process is as follows: figure 1 As shown, dichloromethane should first be passed through crude distillation, then transferred to the impurity removal tank, add sulfur trioxide to remove impurities, and then transfer to the neutralization tank, pass through ammonia gas for neutralization, and after neutralization, use steam to heat to obtain the finished product Dichloromethane; the recovery process is complicated, the process reaction time is long, the production capacity is low, the production cost is high, and it does not conform to the national industrial policy

Images