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.
出处
《工业用水与废水》
CAS
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)
关键词
石英砂负载氧化铁
锑
动力学
吸附机理
iron-oxide coated sand： antimony
kinetics
adsorption mechanism
