石英砂负载氧化铁吸附锑的动力学及其吸附机理研究  

Adsorption of antimony on IOCS:kinetics and mechanisms

作　　者：邓军 施周[2] 许光眉 

机构地区：[1]中国市政工程中南设计研究院,武汉430010 [2]湖南大学土木工程学院水工程与科学系,长沙410082 [3]湖南省建筑设计院,长沙410011

出　　处：《工业用水与废水》2009年第5期19-23,共5页Industrial Water & Wastewater

基　　金：国家自然科学基金(50178029);教育部博士点基金(20030537370)

摘　　要：研究了283、293、313K的温度下,石英砂负载氧化铁(IOCS)对锑的吸附动力学。锑在IOCS表面的吸附可分为两个阶段,吸附反应的前120min为快速吸附阶段;120min后,吸附速率明显变慢。温度升高加快了锑在IOCS表面的吸附速率。用Elovich动力学模型、准一级反应模型、准二级反应模型、二级反应模型和粒内扩散动力学模型对试验数据进行回归分析,准二级反应模型能更好地描述锑在IOCS表面的吸附,各吸附模型的模拟优劣顺序为:准二级模型、二级模型、Elovich模型、准一级模型、粒内扩散模型。给出锑在IOCS表面的吸附机理,Sb(OH)3与IOCS表面羟基经两个阶段的反应,最终生成了双齿表面配合物;SbO(OH)和HSbO2与IOCS表面羟基反应生成单齿表面配合物。The kinetics of adsorption of ant!mony（Sb） from aqueous solutions by iron-oxide coated sand（IOCS） at the temperature of 283, 293 and 313 K were studied. The adsorption of Sb on IOCS was shown to be a two-stage process： rapid in initial 120 min, followed by a much slower stage. The adsorption rate increased with the increasing of the temperature. Through the regression analysis of the experimental data by Elovich model, pseudo-first-order model, pseudo-second-order model, second-order model and intraparticle diffusion model, it could be seen that, pseudo second-order model provided the best fit, and the goodness of fit decreased successively in the order of pseudo-second-order model, second-order model, Elovich model, pseudo-first-order model and intraparticle diffusion model. The mechanism of Sb adsorption on IOCS was proposed. A bidentate surface complex and a monodentate surface complex were formed resulting by the two-stage reaction between Sb（OH）3 and surface hydroxyl groups of IOCS and the reaction between HSbO2（HSbO2） and surface hydroxyl groups of IOCS respectively.

关 键 词：石英砂负载氧化铁 锑 动力学 吸附机理 

分 类 号：X703.5[环境科学与工程—环境工程] TU991.24[建筑科学—市政工程]