土壤2023，Vol.55Issue(6)：1306-1315,10.DOI:10.13758/j.cnki.tr.2023.06.018
铁铝氧化物-层状硅酸盐矿物互作对Cr(Ⅵ)和As(Ⅴ)吸附的影响
Effect of Interaction Between Fe/Al Oxides and Layered Silicate Minerals on Adsorption of Cr(Ⅵ)and As(Ⅴ)
摘要
Abstract
Four single typical soil minerals,kaolinite,montmorillonite,goethite and gibbsite,and two representative soil mineral complexes,goethite-montmorillonite and gibbsite-montmorillonite(mass ratio of 1∶1)were taken as adsorption materials,the effects and mechanisms of the interaction between iron/aluminum oxides and phyllosilicates on the adsorption of Cr(Ⅵ)and As(Ⅴ)were studied using adsorption equilibrium experiment(batch experiment),energy spectroscopy(EDS),infrared spectroscopy,scanning electron microscopy,acid-base titration and zeta potential determination.The data from batch experiment and EDS experiment showed that the adsorption capacity of the two complexes for Cr(Ⅵ)and As(Ⅴ)were less than the average adsorption capacity of the two constituent minerals,which indicated that the interaction between iron/aluminum oxides and montmorillonite reduced the adsorption capacity of the oxides for Cr(Ⅵ)and As(Ⅴ).The characterization results of the surface property showed that after compounded with montmorillonite,the positive charges on the surfaces of goethite and gibbsite were completely neutralized and the charge symbol was reversed.Compared with the theoretical value,the total concentration of the surface sites of the gibbsite-montmorillonite complex changed insignificantly,and the specific surface area decreased.There was no significant difference between the specific surface area and the theoretical value of the goethite-montmorillonite complex,but the concentration of mineral surface sites decreased,and the intensity of the surface hydroxyl infrared absorption peak decreased.The interaction between Fe/Al oxides and layered silicate minerals changed the surface properties of minerals,which may be the main reason for the decrease in the adsorption capacity of the oxides for Cr(Ⅵ)and As(Ⅴ).In conclusion,when evaluating the effectiveness of polluting elements in soils,the influence of the interaction between soil solid components on ion adsorption should be considered.关键词
针铁矿-蒙脱石复合体/表面性质/重金属/吸附Key words
Goethite-montmorillonite complex/Surface properties/Heavy metal/Adsorption分类
农业科技引用本文复制引用
徐海蓉,洪志能,徐仁扣,俞元春..铁铝氧化物-层状硅酸盐矿物互作对Cr(Ⅵ)和As(Ⅴ)吸附的影响[J].土壤,2023,55(6):1306-1315,10.基金项目
国家重点研发计划项目(2020YFC1806801)资助. （2020YFC1806801）
