摘要
研究了Sb^(3+)-OH^--Cl^-体系中配位溶解-沉淀平衡的理论模拟和实验验证,包括Sb OCl、Sb_4O_5Cl_2和Sb_2O_3的水解沉淀过程。对不同配体浓度、不同p H值条件下的锑离子平衡浓度进行理论计算及实验验证,同时分别从溶解平衡和物质转变吉布斯自由能的角度对沉淀产物进行理论分析,并开展验证实验。结果表明,实际锑离子平衡浓度大于理论计算的浓度,其中理论计算的锑离子最小平衡浓度在p H值4.6时为10^(-10.92)mol/L,而实验验证结果表明在p H值5.1时最小平衡浓度为10^(-3.8)mol/L。在一定p H值条件下可以得到不同沉淀产物,无论是在理论计算或是验证实验中均不存在Sb OCl,验证实验中得到了产物Sb_8O_(11)Cl_2·H_2O。
The theoretical simulation and verified experiments on metal separation in a Sb^3+-OH^--Cl^-complexation-precipitation system involving hydrolysis-precipitation reactions of SbOCl, Sb4O5Cl2and Sb2O3were carried out. The equilibrium concentration of [Sb^3+]Twas obtained by calculation and verified by experiments. The precipitates SbOCl,Sb4O5Cl2and Sb2O3were analyzed through the equilibrium concentration of Sb^3+in the solution and the ΔrGΘmof transformation reactions of these materials. It is found that the concentration of [Sb^3+]Tin verified experiments was larger than the theoretical value, where the theoretical minimum concentration of [Sb^3+]Twas 10^-10.92mol/L at pH value of 4.6 and the minimum concentration obtained from the verified experiment was about 10^-3.8mol/L at pH value of 5.1. Different precipitates can be obtained atcertain pH. The SbOCl cannot be obtained both in theoretic calculations and in verified experiments, while the Sb8O11Cl2-H2O was generated in the experiment.
基金
Project(51474257)supported by the National Natural Science Foundation of China
关键词
氯化锑
配位溶解-沉淀平衡
热力学平衡
验证
antimony chloride
complexation-precipitation
thermodynamics equilibrium
verification