关键词: 超声, 酸化, 重金属, 去除率, 形态

Abstract: To improve the chemical elution efficiency of heavy metal contaminated sites, this paper took electronic waste pickling site soil of Longtang Town, Qingyuan city, Guangdong Province as research object, and analyzed the effect of ultrasound and acidification elution, etc. parameters on elution efficiency of Cd, Cu, Pb, and Zn from soil contaminated by electronic waste pickling sites through indoor experiment. The results showed that ultrasonic treatment could effectively improve the elution efficiency of soil heavy metals, especially Cu and Zn. Their elution efficiency increased by 9.65% and 15.3%, respectively. After acidification pretreatment, the elution efficiency of Cd, Cu, Pb and Zn increased by 70.2%, 29.0%, 41.1% and 48.54%, respectively. After acidification treatment, the soil pH reduced from 6.89 to 4.00, and the contents of acid extractable of Cd, Cu, Pb and Zn increased by 10.8%、1.26%、11.1%、11.9%. Acidification treatment could turn reducible, which was difficult to be eluted by EDTA into acid extractable and oxidizable that can be eluted easily by EDTA, and thus enhanced the elution efficiency of EDTA on soil heavy metals. Therefore, ultrasound, acidification pretreatment could be used as assistive technology for improving the elution efficiency of soil heavy metals by EDTA.

Key words: ultrasound, acidification, heavy metal, removal rate, morphology