t-BAMBP-煤油溶液萃取盐湖卤水中铷和铯离子

摘要

The residues of salt lake brine from which potassium had been removed were used to extract Rb+and Cs+together with a sulphonated kerosene (SK) solution of 1.0 mol/L 4-tert-butyl-2-(α-methylbenzyl) phenol (t-BAMBP). Rb+and Cs+were enriched and separated effectively by precipitating Mg2+ before extraction and by scrubbing out K+ and Na+ repeatedly before stripping. The effects of the volume ratio of organic phase to aqueous extraction phase (O/A), alkalinity of aqueous phase (c(OH)−), interference from K+and Mg2+, and ratio the volume of organic phase to aqueous scrubbing phase (O/A′) were investigated. The experimental brine was extracted optimally by 5-stage extraction with 1.0 mol/L t-BAMBP in SK, c(OH−)=1 mol/L, and O/A=1:1. The scrubbing yield of rubidium was only about 10.5%when the extraction solvent was washed 3 times with 1×10−4 mol/L NaOH at O/A′=1:0.5. After 5-stage countercurrent extraction, the final extraction yields of Rb+and Cs+reached 95.04%and 99.80%, respectively.%将工厂提钾后的盐湖卤水作为提取Rb+和Cs+的实验用卤水，将萃取剂t-BAMBP的磺化煤油溶液作为有机相进行萃取。在萃取之前预先沉淀出镁并作为一种产品，在反萃前再多次洗涤分离出大部分的 K+和 Na+，最终使Rb+和Cs+得到有效富集和分离。研究油水相比(O/A)、水相的碱性(c(OH−)、K+和Mg2+的含量及洗涤油水相比(O/A′)对萃取过程的影响。最佳工艺条件为：1.0 mol/L的 t-BAMBP磺化煤油溶液，水相碱性c(OH−)=1 mol/L,油水相比O/A=1：1。当用1×10−4 mol/L NaOH溶液洗涤萃取油相3次，洗涤油水相比O/A′=1：0.5时，铷和铯的洗脱率仅为10.5%。经过5级逆流萃取，最终铷和铯的萃取率分别达到了95.04%与99.80%。