低分子有机酸对三峡库区沉积物吸附Pb2+影响研究

以长江三峡库区万州段消落带区的沉积物为研究对象,通过等温吸附平衡实验研究不同浓度的柠檬酸、草酸对沉积物吸附Pb2+的影响.实验结果表明:消落带沉积物对Pb2+的吸附量随着Pb2+离子平衡浓度的增加而增大,Pb2+平衡浓度在0.08～80 mg/L时,其最大吸附量为8 762.00 mg/Kg.不同浓度的柠檬酸、草酸会在不同程度上抑制沉积物对Pb2+吸附,2 mmol/L柠檬酸对沉积物吸附Pb2+的能力是浓度为4 mmol/L时的1.12倍,草酸条件下为1.02倍.即高浓度的低分子有机酸抑制消落带沉积物对Pb2+的吸附.

Studies on Impacts of Pb2+ Adsorption Quantity in Sedimentsof Three Gorges Reservoir Region by Low Molecular Organic Acids

The sediments of water-level-fluctuating-zone of Wanzhou in Three Gorges Reservoir region was taken as object of study.Through isothermal adsorption equilibrium experiment, this paper studies on the impacts of Pb2+ adsorption quantity in sediments by citric acid and oxalic acid.Results showed that with the increase of Pb2+ equilibrium concentration, the amount of adsorption Pb2+ in sediments are increasing constantly,when Pb2+ equilibrium concentration in 0.08～80 mg/L.The biggest adsorption quantity is 8 762.00 mg/Kg.Different concentrations of citric acid and oxalic acid can inhibit the adsorption of Pb2+ to different extent, 2 mmol/L citric acid adsorption capacity of Pb2+ is 1.12 times the concentration of 4 mmol/L, oxalic acid is 1.02 times in the same condition.