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研究ｐＨ和Ｃａ（Ⅱ）对砷酸根在海水与ＮａＣｌ介质中对水合氧化物和粘土矿物上交换吸附的影响：（１）在酸性条件下和海水及ＮａＣｌ介质中，砷酸根在针铁矿上的交换率Ｅ（％）—ｐＨ曲线呈平顶峰型、在δ－ＭｎＯ呈峰型、在粘土上分别呈双峰型和肩峰型。这是砷酸根存在多种形式与固体表面发生离子／配位子交换以及介质中阴离子竞争交换吸附共同作用的结果。（２）在碱性条件下的海水介质中，砷酸根与水合氧化物和粘土矿物的Ｅ（％）—ｐＨ曲线都呈Ｖ型，这是因为生成了具有一定结构的液—固界面三元络合物之故。（３）在ＮａＣｌ介质中，Ｃａ加入起促进作用，再次证明液—固界面三元络合物生成机理与Ｖ型曲线的内在关系
The effects of pH and Ca (Ⅱ) on the exchange adsorption of arsenate on hydrous oxides and clay minerals in seawater and NaCl media were studied: (1) Under acidic condition and in seawater and NaCl medium, arsenate was on goethite The exchange rate E (%) - pH curve showed a flat peak shape, a δ-MnO peak shape, and a bimodal and shoulder peak shape on the clay, respectively. This is the result of the combination of arsenic species in various forms with ions / ligand exchange on the solid surface and anion exchange competition adsorption in the medium. (2) The E (%) - pH curves of arsenate, hydrated oxide and clay minerals are all V-shaped in seawater under alkaline conditions because of the formation of a ternary liquid-solid interface Complex of the reason. (3) In the medium of NaCl, the addition of Ca (¢ ó) played a catalytic role, proving the intrinsic relationship between the formation mechanism of ternary complex and V-curve at liquid-solid interface