乳状液膜法提取红土矿浸出液中镍

Extraction of Nickel(II) from Acidic Leaching Solution of Laterite Ore with Emulsion Liquid Membrane

采用Span-80-TBP-NH_3·H_2O体系乳状液膜法提取红土矿浸出液中的Ni(II),研究了膜相组成、内水相试剂浓度、膜相与内水相体积比(油内比)、乳水体积比对镍离子提取效果的影响.采用微分法测定并比较了反应的浓度级数nC和时间级数nt.结果表明,膜相组成为Span-80:TBP:石蜡:煤油(体积比)=5:4:2:89、内水相氨水浓度为2mol/L、油内比为1:1、乳水体积比为1:3、外水相硫酸浓度为0.3mol/L的条件下,经过二级提取后,红土矿浸出液中Ni(II)去除率可达80%;由浓度级数(n_C=1)小于时间级数(n_t=2.8)可知,该过程为化学反应控制过程.

The water-oil-water（W/O/W） double-phase emulsion was prepared with Span-80 as surfactant,TBP as oil membrane phase,NH_3·H_2O solution as internal aqueous phase and kerosene as diluting agent.The effects of various factors on the extractive result were examined.The suitable composition of liquid membrane was 5% Span-80,4% TBP,2% paraffin,89%（φ） kerosene.And technological operating conditions were determined as follows：the volume ratio of oil phase to the internal phase was 1：1,and the volume ratio of emulsion to the water phase 1：3.Under the optimal operation conditions,the secondary extraction rate of nickel（II） from acidic leaching solution of laterite ores was up to 80%.The extraction mechanism of nickel（II） with emulsion liquid membrane was discussed by differential method.The results indicated that concentration series（n_C=1） was less than time series（n_t=2.8）.So chemical reaction was controlling step.