硫酸钾和磷酸二氢钾对石灰性土壤和酸性土壤吸附铜离子的影响

Influence of K_2SO_4 and KH_2PO_4 on Adsorption of Copper in Calcareous Soils and Acid Soil

[目的]研究不同电解质浓度、pH值对土壤吸附铜的影响。[方法]采用平衡吸附法研究潮褐土、红壤对Cu2+的等温吸附及不同pH值和电解质对土壤吸附Cu2+及次级吸附Cu2+的影响。[结果]结果表明,低浓度的K2SO4对潮褐土Cu2+的吸附略有促进,KH2PO4浓度高时促进潮褐土Cu2+的吸附,红壤对Cu2+的吸附率随着2种电解质浓度的增加基本呈峰形曲线变化;潮褐土Cu2+次级吸附率随着K2SO4和KH2PO4浓度的增加分别为略有增加和直线降低,K2SO4浓度低时促进红壤对Cu2+的次级吸附,红壤Cu2+次级吸附率随KH2PO4浓度增加而增加;K2SO4和KH2PO4对红壤Cu2+次级吸附率增幅远比Cu2+吸附率增幅高,且KH2PO4对红壤Cu2+吸附的促进作用比K2SO4强,K2SO4对潮褐土Cu2+吸附率与次级吸附率的影响规律一致。[结论]该研究为铜污染土壤的防治提供科学依据。

[Objective]The purpose was to study the effect of different electrolyte concentration and pH value on adsorbing copper of soil. [ Method ] Cu^2＋ adsorption isotherms and the influence of electrolytes on the adsorption and sequential sorption of Cu^2＋ in meadow cinnamon soil and red soil were investigated. [ Result ] The results showed that low concentration of K2SO4 slightly promoted Cu^2＋ adsorption in meadow cinnamon soil, the higher concentration of KH2PO4 promoted Cu^2＋ adsorption. The amount of Cu adsorption on red soil varied in the peakshape-like curves with the concentration of the two kinds of electrolytes. The sequential adsorption of Cu in meadow cinnamon soil slightly increased and decreased with rising concentration of K2SO4 and KH2PO4 , respectively. Lower concentration of K2SO4 promoted sequential adsorption of Cu^2＋ in red soil. Cu^2＋ sequential adsorption in red soil also increased with increasing concentration of KH2PO4. The increment of Cu^2＋ sequential adsorption in the presence of K2SO4 and KHgPO4 was much higher than that of Cu^2＋ adsorption in red soil. Moreover, the promotion of KH2 PO4 to Cu^2＋ adsorption in red soil was stronger than that of K2 SO4. The influence of K2 SO4 on Cu^2＋ sequential adsorption and Cu^2＋ adsorption in meadow cinnamon soil was similar. [ Conclusion] This research will provide the scientific basis for control copper pollution in soil.