关键词: 弗雷德盐, 酸雨, 土壤淋洗, 浸镉, 除镉

Abstract: Simulated acid rain （pH=4） was taken to leach high-cadmium contained soil （total cadmium content is 10.590 mg/kg）.Results showed that the simulated acid rain′s leaching rate of cadmium from soil was only about 1% of total cadmium.But the content （0.108 mg/L） of cadmium in leaching solution was still much higher than allowable ejection wastewater standards of GB 3838—2002 and GB 18918—2002（ <0.01 mg/L）.Therefore it must be treated.Friedel′s salts is an artificially synthesized layered double-hydroxylated complex with polyaluminum as raw material.It can remove the ions of cadmium in leaching solution with the forms of isomorphous substitution，adsorption，or coprecipitation.Results showed large amount of Al³⁺ and Fe³⁺ will affact the Friedel′s salt′s removing effect of cadmium in leaching solution.However，the cadmium content in the treated leaching solution can still reach the town sewage treatment plant emission standard of GB 18918—2002.

Key words: Friedel&prime, s salts；acid rain；soil flushing；leaching of cadmium；removal of cadmium