低分子量有机酸对棕壤吸附铜效果的影响

Effect of Low Molecular Weight Organic Acid on Adsorption of Cu^(2+) in Brown Soil

[目的]根据土壤类型、重金属类型及其相互作用的环境条件,选择合适的有机酸种类和浓度。[方法]研究了3种低分子量有机酸(草酸、柠檬酸和酒石酸)对棕壤吸附铜的影响。[结果]加入相同浓度的3种低分量有机酸后,土壤对铜的吸附量随着外加铜离子浓度的增加而增加,但吸附率随着外加重金属离子浓度的增加而减小。有机酸可以促进土壤对重金属铜的吸附,促进能力为酒石酸<草酸<柠檬酸。[结论]低分子量有机酸可以调控土壤中重金属的有效性,从而提高重金属污染土壤的修复效率。

[ Objective] The optimal kind of organic acid and its concentration were selected according to the soil types, kinds of heavy metal and the interaction [Method] The impact of three low molecular weight organic acids （oxalic acid, citric acid, tartaric acid） on the absorption of Cu^2＋ by brown soil was analyzed. [Result] After adding three acids into brown soil with the same concentration respectively, the absorbing capacity of Cu^2＋ by brown soil increased. However the absorption ratio of Cu^2＋ showed a converse phenomenon in the same condition. Organic acid could pronrpt the ability of soil absorbing heavy metals, and the prompting ability of three organic acids was as follows： tartaric acid was the best, oxalic acid was medium and citric acid was of the lowest ability, [ Conclusion ] The validity of heavy metal in the soil could be regulated by the low molecular weight organic acid, And the remediation efficiency couM be improved in the soil polluted by the heavy metal