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

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.