摘要
Extraction of V（V） and Cr（III） from acidic sulfate leach liquors of ilmenite using 0.4 mol/L Aliquat 336 chloride in kerosene was carried out. Different parameters affecting the extraction process such as equilibrium time, sulfate concentration, Aliquat 336 concentration, equilibrium p H and the extraction temperature were investigated. Extraction of V（V） and Cr（III） by Aliquat 336 involved anion exchange mechanism, and the extracted species are [（VO2SO4）R4N]org at low equilibrium p H for V（V） and [R4N-Cr（OH）4]org at high equilibrium p H for Cr（III）. Calculated thermodynamic parameters show that the extraction process is endothermic reaction for V（V） and exothermic for Cr（III）. Also, calculated values of ？Gex and ？Sex indicate that the extraction reactions of V（V） and Cr（III） proceed as non-spontaneous reaction is more random. V（V） and Cr（III） were stripped, precipitated, separated and calcined at 500 °C for 2.0 h to produce the corresponding oxide in pure form after rinsing and drying.
采用0.4 mol/L煤油稀释的甲基三烷基氯化铵从钛铁矿的酸性硫酸盐浸取液中萃取V(V)和Cr(III)。研究不同参数如平衡时间、硫酸盐浓度、甲基三烷基氯化铵浓度、平衡p H值和萃取温度对萃取过程的影响。利用甲基三烷基氯化铵萃取V(V)和Cr(III)包含了阴离子交换机制,对于V(V),在低平衡p H值时萃取物为[(VO2SO4)R4N]org,而对于Cr(III),在高平衡p H值时萃取物为[R4N-Cr(OH)4]org。计算的热力参数表明,对于V(I),萃取过程是一个吸热反应,而对于Cr(III),萃取过程是一个放热反应。?Gex和?Sex的计算值表明,V(V)和Cr(III)的萃取反应为自发随机进行的。V(V)和Cr(III)经剥离、沉淀、分离后,在500°C煅烧2.0 h,经过冲洗和干燥后,得到相应的纯氧化物。
