Abstract:In the process of lithium extraction from old brine, the extraction method has the advantages of high selectivity and high yield in boron extraction from old brine in salt lakes. An extraction experiment was conducted on boron from brine of a salt lake in Qinghai Province, and the extraction mechanism of boron and the optimal extraction and stripping conditions were determined. The research results indicate that the boric acid extraction process is an esterification reaction process, and the esterification reaction between C8H18O and H3BO3 produces a cosolvent, namely 2C8H17O—B—OH. At an acidity pH value of ~1.5 in the extraction solution, the organic phase was composed of 50% isooctanol and 50% sulfonated kerosene. Compared with O/A=1, the concentration of boric acid loaded on the organic phase after a single extraction was 18.08g/L, and the single-stage extraction rate of boric acid was 92.94%. When the actual concentration of loaded organic phase boric acid is 51.49g/L, the stripping rate is 78.06% compared to O/A=1, and the boric acid concentration in the stripping solution is 40.19g/L.The study aims to provide theoretical basis and data support for the industrial design of boron extraction.