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Isopropanol (IPA) is widely used as solvent in pharmaceutical industry such as cephalosporin production process.However,the complexity of components in the solvent and the existence of azeotropic point for IPA and water make the recovery of IPA very difficult,which often requires high energy consumption and operation cost [1,2].Pervaporation technology based on NaA zeolite membranes has been considered as an economic technology for dehydration of organics with azeotropic point [3,4].In this work,dehydration of isopropanol from industrial cephalosporin production by NaA zeolite membranes was reported.NaA zeolite membranes with 80 cm in length and 12.8 mm in outer diameter were prepared in our group cooperating with Nanjing Jiusi High-Tech Company in China.An industrial-scale facility with 52 m2 membrane area was built for IPA dehydration.Distillation of raw IPA solvent from cephalosporin production was carded out to remove impurities including salts,colored substances and high-boiling-point organics before pervaporation.The distilled IPA solvent had a water content of 15 ~ 20 wt%,which was then introduced into the pervaporation facility.The facility was operated at 95 ~ 100 ℃,which had an average membrane flux of 1 ~ 1.5 kg·m-2·h-1 and water content in product less than 2 wt%.Much work was done on the improvement of stability for the dehydration process.It was found that the pH value of IPA solvent had a strong effect on the life of membrane tubes.The pH adjusted between 7 ~ 8 could significantly improve the stability of pervaporation process.Until now,the separation has been operated over 9 months in a pharmaceutical plant,which suggested a promising application for NaA zeolite membrane in pharmaceutical production.