【作者】 王倩；

【导师】 冯其明；

【作者基本信息】 中南大学 ， 矿物加工工程， 2011， 硕士

【摘要】 纤蛇纹石是三八面体层状结构硅酸盐矿物,因具有较大的比表面积和大量的羟基与不饱和键,而拥有较好的吸附性能和改性基础。目前,已有利用蛇纹石族类矿物处理含铜废水的报道,但研究内容多局限于单一试验因素对吸附效果的影响,且研究结果缺乏理论性和系统性。本文以纤蛇纹石为对象,系统研究了改性前后纤蛇纹石对铜离子吸附行为及其机制。研究结果可为纤蛇纹石及类似硅酸盐矿物在金属阳离子废水处理中的应用提供理论依据。论文所取得的主要研究结果及创新如下：(1)在水相体系下,实现了硅烷偶联剂γ-APS对纤蛇纹石的表面改性。测试分析结果表明,偶联剂成功接枝于纤蛇纹石表面。(2)影响纤蛇纹石吸附Cu2+的主要因素有温度、pH值和初始浓度,改性后纤蛇纹石对Cu2+的吸附能力有较明显提高,吸附量增加0.235mmol/g,去除率提高33%。(3)改性前后纤蛇纹石对Cu2+的吸附符合准二级动力学吸附模型。纤蛇纹石改性可以提高吸附平均反应速率与初始反应速率。阐述了温度、pH值、初始浓度等主要因素对改性前后纤蛇纹石吸附动力学的影响途径。(4)改性前Cu2+与纤蛇纹石外羟基中的氢质子发生离子交换而被吸附,交换作用力主要是偶极作用力和氢键力。改性后吸附机理除离子交换之外,Cu2+还与表面改性剂中的氨基形成配合物而被吸附。更多还原

【Abstract】 Chrysotile is a typical tubular phyllosilicate constituted by repeating sheets of basic Mg(OH)2 and acidic SiO2 groups. Chrysotile asbestos have certain adsorption performance and modification basic because of special structure:a large specific surface area, unsaturated bonds and surface hydroxyl. Currently, although there are few reports about the use of serpentine group minerals to deal with wastewater containing copper, these researches are more confined to a single test on adsorption effect, lacking of theoretical studies and systematism. This article focuses on the above questions, selecting a silane coupling agentγ-APS containing amino group as modified resin, treating chrysotile in water phase with single experimental condition factor, then it analyzes the modification mechanism. Adsorption behavior and dynamics are studied systematically. These results provide theory basis for application of chrysotile in wastewater treatment. Major conclusions and innovations of this thesis are obtained as follows:(1) Chrysotile can be modified by a silane couping agent namedγ-APS in the water system. The analysis test results reveal that the coupling agent has been grafted onto the chrysotile surface successfully.(2) Main factors of adsorption by Cu2+ on chrysotile are temperature, pH value, and initial concentration of copper ions. The capacity that Cu2+ ions adsorb on modified chrysotile has been significantly increased. The adsorption increased 0.235mmol/g, with removal rate of 33%.(3) The adsorption of Cu2+ on modified chrysotile can coincide with the pseudo-second order reaction kinetics model. The modification could enhance the adsorption average reaction rate and the initial reaction rate. The effect ways of main factors, like temperature, pH value and initial concentration, on the adsorption kinetics of modified chrysotile are also explained.(4) The initial concentration provides the necessary driving force to overcome the resistance to the mass transfer of copper between aqueous phase and the solid phase. The main mechanism is due to the ion exchange between copper ions and the H+ of the external hydroxyl groups of the inorganic matrix. The dipole force and hydrogen bonding force are the main driving forces. After modification, copper ions chelating with amidogen is the another mechanism beside ions exchange.更多还原