不同有机酸对2种污染土壤Cd和Zn的浸提效果  

Extraction of Cadmium and Zinc in Two Contaminated Soils from Different Organic Acids

作　　者：曹坤坤 孙燚 王孟[1] 李俊丽 李鑫[1] 庄易 周建利 徐亚伟 阳洋 

机构地区：[1]主要粮食作物产业化湖北省协同创新中心(长江大学),湖北荆州434025 [2]广东真格生物有限公司,广东肇庆526000 [3]华南农业大学农学院,广东广州510642

出　　处：《长江大学学报（自然科学版）》2017年第22期49-53,共5页Journal of Yangtze University(Natural Science Edition)

基　　金：国家重点研发计划重点专项(2016YFD0300900);高等学校大学生创新创业训练计划项目(校级)(2014029)

摘　　要：选用4种低分子天然有机酸(柠檬酸、苹果酸、酒石酸和草酸)和人工合成的有机酸EDTA(乙二胺四乙酸)作为浸提剂,分别在5种浸提浓度(0.0、1.0、2.0、4.0、8.0、10.0mmol/L)下对采自广东省乐昌市的2种铅锌矿废水污染的土壤(分别为中性土壤和酸性土壤)进行浸提试验,比较不同有机酸对土壤重金属Cd和Zn的浸提效果。结果表明,4种天然有机酸浸提的Cd量和Zn量与浸提浓度均呈显著(P<0.05)或极显著(P<0.01)的正相关关系。在较高浸提浓度(10.0mmol/L)下,对中性土壤Cd的浸提能力表现为:EDTA>柠檬酸>苹果酸>草酸>酒石酸;对酸性土壤Cd的浸提能力表现为:EDTA>酒石酸>柠檬酸>苹果酸>草酸;对中性土壤Zn的浸提能力表现为:EDTA>柠檬酸>酒石酸>草酸>苹果酸;对酸性土壤Zn的浸提能力表现为:EDTA>酒石酸>柠檬酸≈苹果酸>草酸。土壤酸碱度对酒石酸浸提土壤Cd和Zn的影响较大,酸性条件有利于提高酒石酸对土壤Cd和Zn的浸提率。Four low molecular weight organic acids including citric acid,malic acid,tratric acid and oxalic acid,and chemically-synthetic chelator EDTA(ethylene diamine tetraacetate)were chosen,the mobilization of Cd and Zn in two agricultural soils contaminated by lead-zinc mining wastewater and different in soil pH from Lechang District,Guangdong Province of China,were studied in batch experiments in 0,1,2,4,8,10 mmol/L.The effect of different organic acids on Cd and Zn was compared.Results showed that the extracted amount of Cd and Zn by four natural organic acids was significantly in positive correlation with organic acid solutions(P< 0.05 and P< 0.01).In high organic acid solutions(10 mmol/L),the extraction sequence of each organic acid for different heavy metals was in the order of EDTA>citric acid>malic acid>oxalic acid>tratric acid(for Cd in neutral soil),EDTA>tratric acid>citric acid>malic acid>oxalic acid(for Cd in acid soil),EDTA>citric acid>tratric acid>oxalic acid>malic acid(for Zn in neutral soil),EDTA>tratric acid>citric acid≈malic acid>oxalic acid(for Zn in acid soil).For acid soil,the extraction rate of Cd and Zn were generally higher than that for the neutral soil.

关 键 词：有机酸 重金属 浸提 污染土壤 

分 类 号：X53[环境科学与工程—环境工程]