A kind of method of reclaiming oxytetracycline hydrochloride from oxytetracycline hydrochloride crystallization mother liquor

Abstract

The invention discloses a method for recycling oxytetracycline hydrochloride from oxytetracycline hydrochloride crystallization mother liquid. The method comprises the following steps: (1) adjusting the pH value of oxytetracycline hydrochloride mother liquid, and filtering to remove insoluble impurities; (2) separating treated filtrate by virtue of an ultrafiltration system so as to obtain a concentrated solution rich in oxytetracycline hydrochloride and an alcohol solution containing a small amount of calcium salt, and recycling methanol from the alcohol solution; (3) carrying out alkalization crystallization on the concentrated solution obtained through ultrafiltration, adding an alkalization reagent during alkalization so as to adjust the pH value, and recycling oxytetracycline, wherein the recycling rate of oxytetracycline reaches 93%-96%; and (4) adding recycled oxytetracycline into absolute methanol which is 5 times of volume dose of oxytetracycline, adding a small amount of calcium chloride to aid dissolving, filtering, adding hydrochloric acid methanol, and crystallizing, so as to obtain oxytetracycline hydrochloride. According to the method, inorganic salt, namely calcium salt, is filtered and separated by virtue of a membrane, the concentrated solution is subjected to alkalization crystallization to generate oxytetracycline, oxytetracycline is refined by virtue of hydrochloric acid ethanol so as to generate oxytetracycline hydrochloride, and the content of obtained oxytetracycline hydrochloride reaches 96%.

Description

technical field The invention belongs to the production technical field of oxytetracycline hydrochloride, and in particular relates to a method for recovering oxytetracycline hydrochloride from oxytetracycline hydrochloride crystallization mother liquor by a membrane separation method. Background technique Oxytetracycline hydrochloride crystallization mother liquor is a kind of highly acidic industrial waste liquid, the main components are solvent methanol and a small amount of water, in which the content of organic matter such as oxytetracycline is 1-3%, and the content of inorganic ions such as calcium ion and chloride ion Around 4%. The waste liquid produced in the production of oxytetracycline hydrochloride generally has a large amount of solvent (generally, the amount of waste liquid is more than 5 times that of oxytetracycline hydrochloride production), and the high acidity and antibiotic components make it difficult to carry out biodegradation methods. industrial was...

AI Technical Summary

Problems solved by technology

The waste liquid produced in the production of oxytetracycline hydrochloride generally has a large amount of solvent (generally, the amount of waste liquid is more than 5 times that of oxytetracycline hydrochloride production), and the high acidity and antibiotic components make it difficult to carry out biodegradation methods. industrial wastewater that is difficult to treat