废磷酸系刻蚀液制备电池级磷酸铁  

Preparation of battery grade iron phosphate from spent phosphoric acid based etching solution

作　　者：贾婧 王秋帏 王小赫 胡馨尹 吴旭[1] JIA Jing;WANG Qiuwei;WANG Xiaohe;HU Xinyin;WU Xu(School of Environmental Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Hubei Yongshao Science and Technology Co.,Ltd.,Qianjiang 433122,China)

机构地区：[1]华中科技大学环境科学与工程学院,湖北武汉430074 [2]湖北永绍科技股份有限公司,湖北潜江433122

出　　处：《化工环保》2023年第4期484-491,共8页Environmental Protection of Chemical Industry

摘　　要：以废磷酸系刻蚀液为原料、铁粉为铁源、H_(2)O_(2)为氧化剂,采用氧化沉淀法一步合成结晶态FePO4。考察了铁磷摩尔比、反应温度、H_(2)O_(2)投加量、pH、煅烧温度对FePO4制备的影响,利用XRD、SEM等手段表征了FePO4的形貌和晶体结构。实验结果表明,在铁磷摩尔比1.000、反应温度90℃、n(H_(2)O_(2))∶n(H3PO4)1.05、pH 2.2~2.4、煅烧温度600℃的最佳工艺条件下,废刻蚀液中PO43-、NO3-、醋酸的去除率分别为87.70%、87.42%和90.25%,FePO4的产品转化率为77.99%,所制备的FePO4晶体结构规则,结晶度高,粒径为2.0~6.0μm,铁、磷质量分数和杂质元素含量等指标均能满足《电池用磷酸铁》(HG/T 4701—2021)的要求。Crystallized FePO4 was synthesized in one step by oxidation precipitation method using spent phosphoric acid based etching solution as raw material,iron powder as iron source and hydrogen peroxide as oxidant.The effects of Fe-P molar ratio,reaction temperature,hydrogen peroxide amount,pH and calcination temperature on the preparation of FePO4 explored.The morphology and crystal structure of ferric phosphate were characterized by XRD and SEM.The experimental results show that under the optimum conditions of Fe-P molar ratio 1.000,reaction temperature 90℃,n(H_(2)O_(2))∶n(H3PO4)=1.05,pH 2.2-2.4,calcination temperature 600℃,the removal rate of PO43-,NO3-and acetic acid in the spent etching solution is 87.70%,87.42%,90.25%,respectively,and the conversion rate of product FePO4 is 77.99%.The prepared FePO4 crystal has a regular structure,high crystallinity,and a particle size of 2.0-6.0μm,and the mass fraction of Fe and P,as well as the content of impurity elements,can meet the requirements of industry standard“Iron Phosphate for Batteries”(HG/T 4701—2021).

关 键 词：磷酸铁 磷酸系刻蚀液 锂离子电池 沉淀 

分 类 号：X703[环境科学与工程—环境工程]