天然水中可溶性硅酸与铝盐作用机理探讨  

Reaction Mechanism of Soluble Silicic Acid with Aluminum in Natural Water

作　　者：王文东[1] 杨宏伟[1] 蒋晶[2] 祝万鹏[1] 蒋展鹏[1] 

机构地区：[1]清华大学环境科学与工程系,北京100084 [2]北京科技大学土木与环境工程学院,北京100083

出　　处：《化学学报》2008年第23期2625-2630,共6页Acta Chimica Sinica

基　　金：美铝基金;国家自然科学基金(No.50238020)资助项目.

摘　　要：通过考察单核铝和溶解铝浓度的变化,对天然水体中溶解性硅酸与铝盐的反应机理进行研究.试验过程中,采用8-羟基喹啉荧光分光光度法测定铝浓度并结合热力学计算进行机理验证.结果表明:单体硅酸和聚硅酸主要与溶液中的单核铝反应生成溶解性硅铝酸盐.单体硅酸与单核铝的结合能力较弱;聚硅酸与单核铝的结合能力则较强,反应产物主要为二啮或三啮配合物.溶液pH对反应过程有着重要影响,偏碱性环境对硅酸与单核铝间的反应具有促进作用.The reaction mechanism between soluble silicic acid and aluminum in natural water was studied by the detection of concentrations of monomer and soluble aluminum. The concentrations of aluminum were determined by an 8-hydroxyquinoline fluorometric method, and the mechanism was confirmed by thermodynamic calculation. The results indicated that both the monomer and polymer silicic acids mainly reacted with the monomer aluminum to form soluble aluminosilicates. The capacity of combination between monomer silicic acid and monomer aluminum was weak, while it was stronger between the polymer silicic acid and monomer aluminum and the products were mainly bidentate or tridentate coordination compounds. During the reaction process, pH played an important role that the reaction could be notably promoted in slightly alkaline solution.

关 键 词：硅铝酸盐 天然水 单体硅酸 聚硅酸 荧光分光光度法 

分 类 号：O611.3[理学—无机化学]