| 摘要: |
| 通过研究氯化钠溶液中磷酸盐在4种固体粒子（针铁矿、δ－氧化锰、伊利石和高岭石）上的交换等温线及钙对上述交换等温线的影响，发现磷酸盐液－固界面作用的台阶型等温线（2个台阶），可用分级离子／配位子交换等温式定量描述。钙能够促进磷酸盐在针铁矿和δ－氧化锰上的交换作用，其机理是交换在固体粒子上的钙再结合溶液中的磷酸盐，形成表面无机三元络合物。 |
| 关键词: 磷酸盐交换作用 液－固界面作用 台阶型等温线 表面三元络合物 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，49376269号;国家教委博士点基金资助项目 |
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| THE ANION-EXCHANGE OF PHOSPHATE ON SOLID PARTICLES IN SEAWATER THE PLATEAU ISOTHERMS OF PHOSPHATE ON SOLID PARTICLES IN SEAWATER |
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Zhao Hongbin1, Liu Liansheng2, Zhang Zhengbin2
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1.Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023;2.Institute of Marine Chemistry, Ocean University of Qingdao, Qingdao 266003
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| Abstract: |
| Investigation of the isotherms of phosphate on goethite, δ-MnO2, illite and kaolinite in NaCl solution revealed plateau isotherms of phosphate on the solid particles. The isotherm equation of stepwise ion / coordination particle exchange is proposed to describe the isotherms. It is suggested that the heterogeneity of surface hydroxy of the solid particles results in a stepwise exchange of phosphate on the solid particles. In addition, the effect of Ca(II) on the interaction between phosphate and the solid particles is examined. The plateau isotherms of phosphate on the solid particles still occur in the presence of Ca (II). It is noted that the phosphate exchanged on the solid particles can increase due to Ca(II). The ternary surface complex as a conceptual model is proposed to illustrate the effect of Ca(II) on the interaction between phosphate and the solid particles. |
| Key words: Phosphate exchange, Plateau isotherm, Ternary surface complex |
