硝酸铁和磷酸为原料制备磷酸铁的工艺探讨

Technological Discussion on the Preparation of Iron Phosphate from Iron Nitrate and Phosphoric acid

以硝酸铁溶液、磷酸溶液为原料制备磷酸铁,其最佳工艺条件为:原料物质的量(分别以铁、磷计)配比n(Fe)∶n(P)=1.00∶1.01~1.02,酸度(以硝酸计)含量在45%~50%之间,反应温度80±2℃,加入磷酸铁作为晶种的量为硝酸铁质量的万分之三,搅拌速度1500 r/min,反应时间12 h,反应生成物经负压抽滤,并进一步水洗、离心、干燥即可得到松散且粒度较小的二水合磷酸铁,在此工艺条件下的收率为96.6%,经进一步焙烧脱水得到淡黄色的无水磷酸铁。

Ferric phosphate was prepared from ferric nitrate solution and phosphoric acid solution,the optimum technological conditions were as follows:molar ratio of raw materials(calculated by iron and phosphorus respectively),n(Fe)∶n(P)=1.00∶1.01~1.02;the content of acidity(calculated by nitric acid)is between 45%and 50%,the reaction temperature was 80±2℃,the amount of ferric phosphate as seed was 3/10000 of the mass of ferric nitrate,the agitation speed was 1500 r/min,the reaction time was 12 h,the reaction product was filtered under negative pressure,washed,centrifuged and dried to obtain loose iron phosphate dihydrate with small particle size.Under this condition,the yield was 96.6%,light yellow anhydrous iron phosphate can be obtained after further roasting dehydration.