复合萃取剂在微分散萃取湿法磷酸中的应用

Application of compound extractant in wet-process phosphoric acid by micro-dispersion extraction technique

本文采用名义孔径为20μm的烧结网作为分散介质,以水/磷酸/TBP+异丙醚和水/磷酸/TBP+煤油作为体系,研究了相比、磷酸质量分数、流量对萃取率及单级效率的影响。实验结果表明:水/磷酸/TBP+异丙醚体系的萃取率与单级效率优于水/磷酸/TBP+煤油体系。相比对萃取率及单级效率的影响较大;磷酸质量分数对萃取率的影响较大,对单级效率的影响较小;而流量对二者的影响均较小。以TBP+异丙醚为复合萃取剂,在流量为1000mL/min,磷酸质量分数为50%,相比为4∶1时,萃取率可达44.40%,单级效率83.32%,反萃率80.21%。

Taking sintered wire mesh of nominal pore size of 20 μm as dispersion medium and water / phosphoric acid / TBP ＋ isopropyl ether and water / phosphoric acid / TBP ＋ kerosene as the system,the paper discusses the influence of phase ratio,phosphoric acid concentration and flow on extraction rate and single-stage efficiency.The result demonstrates that the extraction rate of water/ phosphoric acid / TBP ＋ isopropyl ether system and its single-stage efficiency is superior to the water / phosphoric acid / TBP ＋ kerosene system.Phase ratio exerts more influence on extraction rate and single-stage efficiency;the concentration of phosphoric acid influences extraction rate in a comparatively higher degree than single-stage efficiency;however,flow exerts lesser influence on the two element mentioned before.The extraction rate can reach 44.40%,single-stage efficiency 83.32%,stripping rate 80.21% under the condition that TBP ＋ isopropyl ether is compound extractant;flow rate is 1000 mL/min,phosphoric acid concentration is 50%,phase ratio is 4∶1.