扩散渗析膜分离技术在湿法磷酸净化中的应用研究  

Study on membrane separation technology by diffusion dialysis in purification of wet-process phosphoric acid

作　　者：何兵兵 刘旭 谢娟 陈相 He Bingbing;Liu Xu;Xie Juan;Chen Xiang(State Key Laboratory of Efficient Utilization of Medium and Low Grade Phosphate Rock and its Associated Resource,Guiyang Guizhou 550014,China;Wengfu(Group)Co.,Ltd.,Guiyang Guizhou 550014,China)

机构地区：[1]中低品位磷矿及其共伴生资源高效利用国家重点实验室,贵州贵阳550014 [2]瓮福(集团)有限责任公司,贵州贵阳550014

出　　处：《化工矿物与加工》2023年第4期22-26,62,共6页Industrial Minerals & Processing

基　　金：贵州省科技计划项目(黔科合支撑[2022]一般029,黔科合支撑[2021]一般300)。

摘　　要：扩散渗析膜分离技术因能耗和操作费用低且安全环保,已成功应用于冶金行业废酸如硫酸、盐酸和硝酸等的分离回收,磷酸的净化分离由于在传统离子交换膜上的渗透系数低导致P_(2)O_(5)回收率低而限制了该技术的应用。为了将该技术应用于湿法磷酸中的杂质脱除,采用福建某公司生产的聚烯烃类超薄(厚度小于50μm)阴离子交换膜进行湿法磷酸净化试验,得出适宜的操作参数为:浓磷酸进料温度35℃,膜处理通量0.7 L/(m^(2)·h),浓磷酸与水的体积流量比1.0∶1。在优化条件下进行湿法磷酸除杂试验,磷酸MER值从5.81%降至0.93%以下,P_(2)O_(5)回收率在53%以上。此外,浓磷酸经过脱硫预处理再进行膜分离时,磷酸MER值从6.21%降至1.17%以下,P_(2)O_(5)回收率在55%左右。Because of its low energy consumption and operation cost,diffusion dialysis technology had been successfully applied in the separation and recovery of waste acids in metallurgical industry,such as sulfuric acid,hydrochloric acid and nitric acid and it can be operated at high safety and environmental friendly.Due to the low permeability of phosphoric acid on the traditional ion exchange membrane,its application was limited as the low P_(2)O_(5) recovery resulted.In this paper,polyolefin ultra-thin(<50μm in thickness)anion exchange membrane which was produced by a company in Fujian was employed in the membrane purification of wet-process phosphoric acid(WPA).Test results show that the suitable operating conditions of membrane purification were as follows:at concentrated phosphoric acid feed temperature of 35℃,membrane treatment flux of 0.7 L/(m^(2)·h),and volume flow ratio of phosphoric acid to water of 1.0∶1.Under the above conditions,the MER value of phosphoric acid decreased from 5.81%to less than 0.93%,with P_(2)O_(5) recovery of 53%.In addition,after desulfurization pretreatment on concentrated phosphoric acid and followed by membrane separation,the MER value of phosphoric acid was reduced from 6.21%to less than 1.17%,and resulted in 55%P_(2)O_(5) recovery.

关 键 词：扩散渗析 阴离子交换膜 湿法磷酸 净化 磷酸MER值 

分 类 号：TQ126.3[化学工程—无机化工]