Study Of Concentrating The Hydrolysis Mother Liquor By Nanofiltration

2-(2-Amino-4-thiazolyl)-2-methoxyiminoacetic acid (ATMAA) is animportant pharmaceutical intermediates, which is widely used in thesynthesis of new high efficiency antibiotics, such as cephaloridnum. A dozenor more drugs production is directly dependent on producting thehigh-quality ATMAA. Recently, Since ATMAA's production has entered intoits maturity in China, production efficiency is the key to be competitive amongmanufacturers and the competition has intensified. At the meantime, withincreasing attending to the environmental protection, environmental costshould not be ignored for the pharmaceutical industry. Only by continuouslyoptimizing technology, improving equipment the pharmaceutical companycan survive in the fierce market competition.Based on full study various technology routes, this paper was startedfrom the production process of ATMAA. It was considered that whatever thetype of synthetic process was, it contained the process of solid-liquidseparation so that a few of products were remained in the mother liquor. Forthe waste of ATMAA, separating and concentrating the mother liquor bynanofiltration technology were proposed. ATMAA can be obtained by further crystallization after concentretion. Meanwhile, the polluting substanceswould be remarkly reduced. Another benefit of ATMAA recovery isdecreasing the difficulty of subsequent water treatment.The stability of the DK1812nanofiltration membrane was determined fordealing with the preparations of ATMAA and actual mother liquor,respectively. It was examined that the impact of different operating conditionson the nanofiltration process. It was obtained that nanofitrationmembrane permeate flux was increasing by the rise of temperature andpressure. It was considered comprehensively about the film stability, thepenetration of the flux and energy issues. The appropriate operating conditionswere the normal temperature and pressure of0.6MPa. In the actual production,after the concentrated the mother liquor can be recycled about60%thoughcooling crystallization, while the permeate COD removal efficiencywas up to60%. The cleaning fluid and cleaning time was chose. Themembrane flux can be effectively restored by the citric acid at pH2-3andthe NaOH solution at pH9-10. The operating conditions were at the pressureof0.3-0.4MPa and temperature controlled range of20-30℃.The economic assessment of the application of nanofiltration technologyin the ATMAA actual production was carried out on the basis of theexperiments. The model of the characteristic parameters in the process wasalso built. The initial investment of nanofiltration process can berecovered within a year. The annual revenue was increased approximately 1.65million. It was confirmed that the process was feasibility in the economic.The building of the model can estimate and forecast the productionprocess and the effect of it. It was guidance and basis for theindustrialization of nanofiltration technology.In the future, the study of the ATMAA production mother liquornanofitration technology can be started from the research and development ofnew membrane, the stability of nanofiltration process and productionautomation.