磷酸铵在(NH_4)_3PO_4-(NH_4)_2WO_4-NH_4OH-H_2O系中溶解度研究  

Equilibrium Solubility of Ammonium Phosphate in (NH_4)_3PO_4-(NH_4)_2WO_4-NH_4OH-H_2O System

作　　者：万林生[1] 周红张 杨亮[1] 王忠兵[1] 梁勇[2] 杨运光 

机构地区：[1]江西理工大学,江西赣州341000 [2]钨资源高效开发及应用技术教育部工程研究中心,江西赣州341000 [3]湖南辰州矿业有限责任公司,湖南沅陵419605

出　　处：《中国钨业》2016年第2期49-52,73,共5页China Tungsten Industry

基　　金：资源与环境领域国家863计划课题(2012AA061902);中国博士后基金特别资助项目(2015T80694);中国博士后基金项目(2013M541879);江西省博士后择优资助项目(2013ky37)

摘　　要：采用等温结晶法研究了磷酸铵在(NH_4)_3PO_4-(NH_4)_2WO_4-NH_4OH-H_2O系中的溶解度。结果表明:低温、高氨浓度下(NH_4)_3PO_4-(NH_4)_2WO_4-NH_4OH-H_2O系中磷酸铵的溶解度非常小,易溶的磷酸铵表现出难溶的特征。温度10℃、氨含量15.6%(质量分数)时,磷酸铵的溶解度可低至0.02%(质量分数,P_2O_5);钨酸铵浓度对磷酸铵溶解度的影响很小;白钨矿磷酸铵分解液氨盐析-冷却结晶回收磷酸铵过程钨基本不结晶析出。研究结果为白钨矿磷酸铵分解液高效回收磷酸铵和初步脱磷奠定了理论基础。The solubility of （NH4）3PO4-（NH4）2WO4-NH4OH-H2O system was measured by the method of isothermal solution saturation.The results show that ammonium phosphate solubility is very low under conditions of low temperature and high ammonia concentration in the （NH4）3PO4-（NH4）2WO4-NH4OH-H2O system.The ammonium phosphate solubility is only 0.02 %（wt.P2O5） in the（NH4）2WO4-NH4 OH solution when temperature is 10 ℃and ammonia content is 15.6 %（wt）,and effect of ammonium tungstate concentration on the solubility of ammonium phosphate is low.Crystal precipitation of tungsten is not occurring from the scheelite decomposition solution in the process of ammonium phosphate recovery by ammonia salting out coupled with cooling crystallization method.This research provides theoretical guidance to the process of recovering ammonium phosphate coupled with removing phosphorus from the leaching solution of scheelite.

关 键 词：磷酸铵 (NH4)3PO4-(NH4)2WO4-NH4OH-H2O系 溶解度 

分 类 号：O645.12[理学—物理化学]