METHOD FOR CLEANING ABSORBENT GASES IN PRODUCTION OF CHLORAL Russian patent published in 1994 - IPC

FIELD: chemical industry. SUBSTANCE: absorbent gases in production of chloral by ethanol chlorination method, containing impurities of chlorine and ethyl chloride are treated in conditions of circulation of water in mixture with ethanol with water content of 11.3-30 mas.%. Temperature of the process is 45-70 C. Content of combined chlorine in mixture is maintained within 0.4-4.9 mas.%. Spent mixture of water and ethanol is directed to production of chloral, stage of ethanol chlorination. Then, absorbent gases are sprayed with aqueous solution of NaOH. Amount of active chlorine in spent alkali solution does not exceed 0.03 g per 10 l of cleaned absorbent gases. Method provides for reduction of amount of sewage down to 3.6 l per ton of chloral. EFFECT: reduced amount of contaminated sewage. 2 cl, 1 tbl