Abstract: The formula for microemulsion system with saponified HA of NaOH has been studied. Through extraction test to Cd2＋ and Zn2＋ from feed phase using the microemulsion system of HA／kerosene／NaOH, different factors effecting extraction rate of Cd2＋ and Zn2＋, such as the mass ratio of HA, the concentration of NaOH, the ratio of volume between microemulsion and feed phase were investigated. The experimental results show the primary extraction rate of Cd2＋ was 99.23 ％ and the Zn2＋ was 97.51 ％ when the volume ratio of HA to kerosene was 1∶2.5,the concentration of NaOH was 1.5 mol／L, the ratio of volume between microemulsion and wastewater was 1∶3, the extraction time was 6 min. And the experimental results show the rextraction rate of Cd2＋ was 98.29 ％ and the Zn2＋ was 97.38 ％ when the pH of the oil phasead justed to 1 and the ratio of volume between oil phasead and water was 1∶3. This microemulsion system exhibits several advantages including good stability, simple process, lower cost,high efficiency of extraction.

Key words: microemulsion, HA, Cd2+, Zn2+, extraction, rextraction