不同温度下NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O体系溶解度的测定  

Determination of solubility of system NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O at different temperatures

作　　者：张杰[1] 朱静[1] 史连军 王诗瀚 陈丽琼 孟泽宇 李天祥[1] ZHANG Jie;ZHU Jing;SHI Lian-jun;WANG Shi-han;CHEN Li-qiong;MENG Ze-yu;LI Tian-xiang(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,Guizhou Province,China;State Key Laboratory of Efficient Utilization for Low Grade Phosphate Rock and Its Associated Resources,Guiyang 550014,Guizhou Province,China)

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025 [2]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

出　　处：《化学工程》2023年第4期34-38,共5页Chemical Engineering(China)

基　　金：国家自然科学基金资助项目(21868010);贵州省科技计划项目(黔科合平台人才[2018]5781号)。

摘　　要：采用等温溶解平衡法研究303.15,323.15,333.15,343.15 K下三元体系NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O的固液相平衡关系,平衡固相组成采用湿渣法与X射线衍射法相结合的方法进行鉴定。结果表明:三元体系NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O在各个温度下均有1个共饱和点、2条单变量曲线、3个结晶区。运用Wilson模型和NRTL模型对研究体系进行关联计算,结果表明:NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O体系的Wilson模型关联值的RAD=2.68%,RMSD=0.11;NRTL模型关联值的RAD=1.78%,RMSD=0.71,溶解度理论计算值与实验值吻合良好。最后,用得到的Wilson模型和NRTL模型参数对313.15 K和353.15 K溶解度进行预测,并与文献值对比,效果较好,表明这2个模型可用于303.15—353.15 K体系的相平衡计算。The solid-liquid phase equilibria relationship of the ternary system NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O was studied by isothermal dissolution equilibrium method at 303.15,323.15,333.15 and 343.15 K.The equilibrium solid-phase composition was identified by wet slag method and X-ray diffraction method.The results show that there are one cosaturation point,two univariate curves and three crystallization regions at various temperatures in the ternary system NH_(4)H_(2)PO_(4)-(NH_(2))_(2)CO-H_(2)O.The Wilson model and NRTL model were used to correlate experimental data of the research system.The results show that the relative average deviation(RAD)and root mean square deviation(RMSD)of the experimental and calculated values for the Wilson model are 2.68%and 0.11,the RAD and RMSD for NRTL model is 1.78%and 0.71,respectively.The theoretical calculation value of solubility is meet with the experimental value.Finally,the Wilson model and NRTL model were used to predict the solubility data of the system at 313.15 K and 353.15 K,which is agreement with the literature value;and indicate that the two models have certain prediction ability for the system of 303.15-353.15 K.

关 键 词：(NH_(2))_(2)CO NH_(4)H_(2)PO_(4) 溶解度 Wilson模型 NRTL模型 

分 类 号：TQ44[化学工程—化学肥料工业]