微波萃取土壤中重金属Cr的形态分析研究

Microwave Extraction of Heavy Metal Cr from Soil for Morphological Analysis

运用Tessier法和微波萃取法研究了长沙铬渣场铬渣堆集区土壤中重金属铬的形态分布,并研究了铬的生物可利用性。结果表明,微波萃取法和传统的Tessier法得出的Cr的形态分布规律相同,即:残渣态>有机结合态>铁锰氧化物结合态>碳酸盐结合态>可交换离子态,并且整个实验所需时间仅为传统方法的1/76。但微波萃取法的可交换离子态和碳酸盐结合态的萃取效率较低,需要进一步优化实验条件以获得理想的实验结果。两种提取方法对土壤中重金属的生物利用性的分析结果均为:不可利用态>潜在利用态>有效态,表明该区域内土壤中金属Cr的生物可利用态含量较少。

To analyze the morphological distribution of heavy metal Cr in the soil of chromium residue stacking area of Changsha chromium residue field and research the bioavailability of Cr using the methods of Tessier and microwave extraction.The results showed that the morphological distribution of Cr analyzed by the two approaches of Tessier and microwave extraction was similar,that was residue state > organic bound state > Fe-Mn oxide bound state > carbonate bound state > exchangeable ionic state,and the time required for the entire experiment is only 1/76 of traditional method.However,extraction efficiency of exchangeable ionic state and carbonate bound state using microwave extraction method was low which need to explore the optimal experiment conditions to acquire the best experiment results.The bioavailability analysis results of heavy metal in soil by two approaches were: non-usable state >potential utilizable state>available state,which suggested that the bioavailability of Cr in soil of this area was low.