Thermodynamic simulation of stepwise precipitation of NH_(4)VO_(3)and NaHCO_(3)from carbonating Na_(3)VO_(4)solution  

碳酸化Na_(3)VO_(4)溶液分步沉淀NH_(4)VO_(3)和NaHCO_(3)的热力学模拟

作　　者：Fan-cheng MENG Yong-chao WANG Xin CHAI Ya-hui LIU Li-na WANG De-sheng CHEN 孟凡成;王永超;柴鑫;刘亚辉;王丽娜;陈德胜(中国科学院过程工程研究所战略金属资源绿色循环利用国家工程研究中心,北京100190;中国科学院大学化学工程学院,北京101408)

机构地区：[1]National Engineering Research Center for Green Recycling of Strategic Metal Resources,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China [2]School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing 101408,China

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第10期3386-3399,共14页中国有色金属学报（英文版）

基　　金：the financial supports from the National Natural Science Foundation of China(No.22078343);Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0430103);the National Key Research and Development Program of China(No.2018YFC1900502)。

摘　　要：Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_(4)VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_(4)VO_(3)by adding(NH_(4))_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_(4)VO_(3)and NaHCO_(3),respectively.通过热力学模拟,设计了基于调节正钒酸钠溶液的碳酸化以分步沉淀偏钒酸铵和碳酸氢钠的新工艺。首先,利用Bromley-Zemaitis活度系数模型建立含钒酸盐和碳酸盐的水溶液中V(V)的化学形态新模型。然后,进行常压或高压碳酸化过程的热力学平衡计算,以揭示钒、碳、钠和杂质的行为。为了保证钒产品的纯度和收率,正钒酸钠溶液先碳酸化至pH值为9.3~9.4,然后加入碳酸铵得到偏钒酸铵沉淀。沉钒后溶液深度碳酸化至最终pH值为7.3~7.5,以沉淀碳酸氢钠,剩余溶液返回用于溶解正钒酸钠晶体。最后,验证实验表明,溶液中99.1%的钒和91.4%的钠分别以偏钒酸铵和碳酸氢钠的形式得到回收。

关 键 词：thermodynamics sodium orthovanadate speciation model CARBONATION vanadium precipitation sodium bicarbonate 

分 类 号：TQ114.1[化学工程—无机化工] TQ113.7