纳米tio2柱撑膨润土系列光催化剂对染料废水降解性能的研究.doc

纳米纳米 TiO2柱撑膨润土系列光催化剂柱撑膨润土系列光催化剂对染料废水降解性能的研究对染料废水降解性能的研究环境科学与工程学院II摘要摘要纺织印染行业排放的废水中所含染料物质结构稳定，难以生物降解，进入生态环境将带来众多的环境问题，对该类废水的处理受到国内外研究者的普遍关注传统的物理化学方法（如活性炭吸附、超滤，反渗透、加入絮凝剂絮凝和离子交换等）虽然有效，但只是将有机污染物从水相转移到另一相中，很可能带来二次污染物理化学与生物方法相结合的处理方法存在操作复杂，处理成本过高等问题光催化技术不仅有操作简单、能量消耗较低、减少二次污染、反应条件比较温和等特点，还能把有机污染物分解并转化为 H2O、CO2、PO43-、SO42-、NO3-、卤素离子等无机小分子，达到完全无机化的目的由于 TiO2具有高催化活性、良好的稳定性、无毒无害和价格低廉等特点，使其成为光催化材料的研究热点但其粉末状存在形态难以从处理后的悬浮液中分离出来，严重限制了 TiO2的应用近年来，人们尝试将 TiO2负载在活性炭、不锈钢、沸石分子筛、玻璃等载体上，制成负载型 TiO2光催化剂，改善了 TiO2的形态和催化性能，同时,通过掺杂金属离子也可以提高其催化性能。

膨润土是以蒙脱石为主要成分的一类层状硅酸盐粘土矿物，其内部层与层之间有约为1 nm 的层间隙，并具有较强的离子交换性和吸附性，原料来源丰富、价格低廉，是一种高效、高选择性的光催化剂载体本论文以膨润土为载体，采用溶胶-凝胶法制备掺杂钇离子的TiO2柱撑膨润土纳米复合光催化剂，运用红外光谱（FT-IR） 、X射线衍射（XRD） 、电子能谱仪（XPS）和紫外-可见光漫反射（DRS）对纳米复合光催化剂进行了表征，在高压汞灯照射下，分别选择甲基橙溶液、刚果红溶液、活性艳蓝19溶液模拟染料废水为研究对象，评价了其吸附与光催化性能，同时讨论了染料结构不同对光催化性能的影响实验结果表明：掺杂钇离子的TiO2柱撑膨润土负载型纳米光催化剂比TiO2柱撑膨润土负载型纳米光催化剂具有更强的吸附光催化降解性能；三种染料吸附光催化降解难易顺序为：甲基橙溶液>活性艳蓝溶液19>刚果红溶液以刚果红溶液为例，讨论了溶液pH值、初始浓度和外加H2O2对光催化性能的影响结果表明，适当的pH、溶液初始浓度和外加适量的H2O2可以加速光催化氧化反应速率关键词：关键词：柱撑膨润土，光催化，吸附，钇，二氧化钛，染料废水IIIAbstractTextile dyes are an abundant source of coloured organic compounds that present an increasing environmental danger. During dye production and textile manufacturing processesa large quantity of wastewater containing dyestuffs with intensive colour and toxicity can be introduced into the aquatic systems. A variety of physical, chemical and biological methods are presently available for treatment of textile wastewater. Biological treatment is a proven technology and is cost-effective. However, it has been reported that the majority of dyes are only adsorbed on the sludge and are not degraded. Physical methods such as ion-exchange, adsorption, air stripping, etc, are also ineffective on pollutants which are not readily adsorbable or volatile, and have the further disadvantage that they simply transfer the pollutants to another phase rather than destroying them. Heterogeneous photocatalysis has been considered as a cost effective alternative for the purification of dye containing wastewater. Indeed recent studies have demonstrated that photocatalysis can may lead to complete mineralization of organic carbon into H2O、CO2、PO43-、SO42-、NO3-. The most investigated photocatalyst is titanium dioxide. Application of TiO2 in photocatalytic processes is based on its remarkable activity, chemical stability and also on itsnon-toxic properties. But photocatalysts are often applied as suspensions, costly problems associated with catalyst leaching, settling, floatation and the need for eventual catalyst separation by filtration during post treatment, hinder their wide scale application in industry. Therefore, catalyst immobilization related research has attracted wide attention.Bentonite is montmorillonite as the main components of a type layered silicate clay minerals, its internal layer and the layer between about 1 nm gap layer, and have a strong ion exchange and adsorption, rich source of raw materials, low prices, is a high-performance, high-selective catalyst. In this paper dope yttrium ions TiO2 pillared bentonite photocatalyst was prepared and characterized by FT－IR,XRD,SPS and DRS. Under high pressure mercury lamp irradiated, the adsorption and photocatalytic properties was evaluated by degradation of methyl orange , reactive blue 19 and congo IVred and discussed the influence of different structures of dye on the photocatalytic properties. The result showed that yttrium doping TiO2 permeated the interlayer of bentonite had a high photocatalytic degradation of dye wastewater activity. The order of three dye decolorization was methyl orange > reactive blue 19 > congo red., Several factors such as pH, substrate concention and the presence of H2O2, which affect the efficiency of adsorptive and photocatalytic degradation, are discussed using congo red as an example. It has been found that the efficiency of degradated dyes can be enhanced by appropriate pH, substrate concention and H2O2 additive.Keywords：pillared bentonite, absorption, photocatalytic, yttrium, titanium dioxide, dye wastewaterV目 录1. 综述 .......................................................................11.1 染料废水概述 ..........................................................11.1.1 染料的种类 .......................................................11.1.2 染料的发色原理 ...................................................11.1.3 现有的主要治理方法优点和缺点 .....................................21.2 光催化概述 ............................................................41.2.1 光催化原理 .......................................................41.2.2 二氧化钛的光催化性能研究 .........................................51.3 膨润土概述 ............................................................61.3.1 膨润土的化学性质 .................................................61.3.2 膨润土资源分布 ...................................................81.3.3 柱撑膨润土的研究背景及现状 .......................................91.4 研究目的与内容 .......................................................102. 研究方法 ...........................。