混合醇萃取法深度脱除老卤中微量硼的试验研究

Experimental study on deep removal trace boron in the bittern by mixed alcohol extraction method

为了消除硼在盐湖资源精深加工过程中的不利影响,实现微量硼的深度脱除,以提钾后老卤为原料,采用2,2,4-三甲基-1,3戊二醇、2-丁基-2-乙基-1,3丙二醇与异辛醇组成混合醇作为萃取剂,磺化煤油为稀释剂,进行了萃取平衡时间、温度、pH、相比等单因素试验,获得了最佳工艺参数。结果表明:在最佳工艺条件下,即pH3.0、时间10 min、温度20℃、相比1∶1,单级萃取效率达到99.3%,通过两级反萃,累计反萃效率可达96.9%。经过循环试验表明,再生后的萃取剂具有较高的萃取效率,可循环使用,展现出良好的应用前景。

In order to eliminate the unfavorable effect of boron on the deep processing of salt lake resource,an experiment of trace boron deep removal was conducted.The bittern which had been extracted potassium was used as the raw material.2,2,4-Trimethylpentane-1,3-diol,2-Butyl-2-ethyl-1,3-propanediol and iso-octyl alcohol were mixed as extraction agent,and sulfonated kerosene was used as thinner.The influence of balance time,temperature,the pH of the brine and other factors on extracting boron were investigated so as to get the optimum process parameters.The optimized conditions were pH3.0,10 min,20℃,and phase ratio 1∶1.Under the optimum conditions,single-stage extraction efficiency reached 99.3%,and the cumulative stripping back extraction efficiency reached 96.9%.The cyclic experiments showed that the regenerated extraction agent had high extraction efficiency,can be recycled,with good application prospect.