富铌渣电化学选择性提取铌资源的热力学分析

结合富铌渣多元共生复合的特点,综合比较各种铌资源提取分离的手段,提出采取熔融氧化物电解方法,实现富铌渣中铌、铁元素电化学选择性还原和分离。从理论上分析富铌渣电化学选择性提取铌资源的可行性,计算电化学还原过程中相关反应的Gibbs自由能变化及各氧化物的理论分解电压,讨论可能存在的化学反应及其优先程度,分析电化学过程可能的产物。结果表明:富铌渣电化学选择性提取铌资源是可行的;通过确立适宜的物理化学条件和电化学参数,可实现富铌渣中铌资源的选择性提取分离。熔融氧化物电解提取金属具有流程短、能耗低、污染小等特点,从而为开发绿色环保、高效低耗的铌资源提取技术提供新思路。

Thermodynamic analysis on selective electrochemical extraction of Nb-bearing from Nb-enriched slag

On the basis of the complex symbiosis characteristics for Nb-enriched slag,and comprehensive comparison of various means of resource extraction and separation of niobium,the known technology of mol-ten oxide electrolysis is applied to selective reduce the element of Fe and Nb from the complex multiphase Nb-enriched slag. Thermodynamic analysis of the feasibility of selective electrochemical extraction of Nb-bearing from Nb-enriched slag is carried out. The Gibbs free energy and the decomposition voltage associated with electrolytic temperature for molten oxide was calculated and thermodynamic analysis of the possible reactions and the products were given. The resultes indicate that the selective electrochemical extraction of Nb-bearing from Nb-enriched slag is absolutely feasible. Under the suitable physical-chemical conditions and the electro-chemical parameters,the extraction and separation of iron and niobium from Nb-enriched slag can be effec-tively. The utilization of the niobium resources from Nb-enriched slag by the present method shows their ad-vantages, such as shorter process,lower energy consumption and lower secondary pollution. This is a promsing method due to the development of green,high efficiency and low consumption of the niobium re-source extraction.