硫酸根离子添加顺序对可变电荷土壤吸附铜离子的影响

研究了SO2-4添加顺序对三种可变电荷土壤(昆明铁质砖红壤、徐闻砖红壤和江西红壤)吸附Cu2+的影响,作为对照,也研究了其对恒电荷土壤(黄棕壤、棕壤)以及两种不同矿物(高岭石与针铁矿)吸附铜离子的影响。实验结果表明,在同等条件下,SO2-4添加顺序对两类表面性质不同的土壤吸附Cu2+有着不同的影响。对于恒电荷土壤,SO2-4添加顺序对土壤吸附Cu2+几乎没有影响。同等pH条件下,对可变电荷表面而言,加入CuSO4者具有最高的Cu2+吸附率;对昆明砖红壤、徐闻砖红壤以及针铁矿和高岭石而言,先加入Cu2+者相对先加入SO2-4者Cu2+吸附率更高;对江西红壤而言,上述这个次序则刚好相反。SO2-4浓度和有机质去除对同等pH条件下铜离子吸附率高低的排序并无实质性影响。

Effect of sequences of sulfate addition on adsorption of copper ions by variable caharge soils

Three variable charge soils were used to exam the effects of sulfate addition order on the adsorption of Cu2 , two constant charge soils and geothite, gibbsite were also used. Results indicate that the sulfate addition order has different effects on Cu2 adsorption by two kinds of charge surface soils in the same condition. For the constant charge soils, the addition order of sulfate has no effection on the adsorption of copper ions. On the other hand, the addition of copper sulfate has the highest adsorption of copper ions in the same pH, with the remarkable soil reacted with the sulfate prior to the copper ions for the Alic-Haplic Acrisol, and the remarkable soil reacted with copper ions prior to the sulfate for the Hyper-Rhodic Ferrosol, gibbsite and geothite. In all condition, the concentration of sulfate and de-OM have no remarkable effect on the order.