纳米TiO2(nano-TiO2)在光催化领域已经显示出广阔的应用前景，有选择性的进行掺杂己被证明是一种提高其光催化活性的极其有效的方法。将光催化剂固定化既可以解决催化剂回收难问题，还可以克服悬浮相催化剂稳定性差和容易中毒的缺点。采用传统的固定方法，量子效率往往降低，因而推广应用受到限制；最新的固定化的方法趋向于选择一些具有特殊性能的载体，利用这些载体的大比表面积，强吸附性能，使被降解物与催化剂接触机率增加，从而实现在同一反应器内，吸附和催化的有机结合，大大提高催化剂光降解效果，因此是非常有发展前途的新型光催化材料。本文旨在开展对二氧化钛非金属离子掺杂改性条件、光催化降解有机物动力学及ACF负载技术的研究，探索其最佳制备工艺条件，以期进一步充实光催化剂修饰改性技术、负载及有机污水治理方面的研究。 以四氯化钛、硫酸铵为主要原料，采用溶胶-凝胶法制备了SO42-/TiO2光催化剂，利用XRD、FT-IR进行了表征，并将其用于光催化降解水中微量次甲基蓝溶液。实验表明，SO42-离子的掺杂修饰，使纳米二氧化钛结构明显改善。与纯TiO2比较，改性样品X-衍射峰明显变宽。SO42-离子的修饰可能使表面自由能降低或表面物质扩散系数减小，从而抑制了表面的收缩或离子间的聚集，阻止了催化剂晶粒的长大，导致催化剂的比表面积增大。考察了不同降解工艺条件下纳米TiO2对次甲基蓝的脱色情况，发现光反应器为石英材质，催化剂添加量为1.0～1.5 g/L时，对6～9 mg/L的次甲基蓝溶液可达到最佳的降解脱色效果。常温情况下，对9 mg/L的次甲基蓝溶液，纳米TiO2添加量为1 g/L，在20 W紫外灯照射2 h 后，次甲基蓝脱色率可达98.4 %；可见光照射16 h 后，次甲基蓝脱色率可达56.9 %。次甲基蓝溶液初始浓度在6～15 mg/L的范围内，其光催化降解反应遵循表观一级反应动力学规律。反应的表观速率常数随着溶液初始浓度的增大而减小，半衰期随溶液初始浓度的增大而增加。 ACF吸附次甲基蓝的实验表明，ACF是一种很好的染料吸附剂，吸附次甲基蓝的效果很明显。吸附时，初始吸附速率很大，进而速率急剧减小，最后达到平衡状态。吸附符合Freundlich等温吸附方程，吸附过程符合准一级动力学吸附方程。次甲基蓝溶液初始浓度100 mg/L, 室温下，吸附方程为q=99.7125[1-exp(-0.18177t)]。吸附过程的热力学参数焓变、标准自由能和熵变分别为 106.294 KJ mol-1、-12.654 KJ mol-1和0.399 KJ mol-1 K-1。 用ACF负载TiO2，TiO2颗粒均匀吸附在它的表面中，颗粒粒径小，不易脱落；ACF强度较高，不易粉化，用它作TiO2的载体，不会造成二次污染，有效解决了催化剂难于回收的困难。

Nanocrystalline titanium dioxide finds a broad field of realized and potential applications in the areas of photocatalysis. Selective doping of the crystalline matrix has been proved to be an efficient route to improve the photocatalytic activity of nano-TiO2 when it was doped with various metal captions. The difficulty of recovery、steadiness and inactivation can be resolved by immobilization. The quantum efficiency of immobilized-TiO2 is lower than that of suspended-TiO2 with same TiO2 mass using the traditional substrates. At present, the substrates, which have some specific properties such as high specific surface area for high-adsorption, are regarded as better. The double functions of photocatalysis and adsorption can come true with high efficiency simultaneously. The aim of this dissertation is to initiate the research of the non-metal ion modification and support with ACF of photocatalystst and the decolorization of Methylene blue aqueous solution and seek after optimal condition and general degradation rules, by which we look forward to building up the base for further research. Nano-sized SO42-/TiO2 particles were prepared from TiCl4 and (NH4)2SO4 by Sol-Gel method and characterized by XRD and FT-IR technologies. Photocatalytic degradation of Methylene blue solution under ultraviolet radiation was carried out using nanoparticle TiO2 as the photocatalyst. It was found that modified-TiO2 remarkably improved its photocatalytic activity. Compared to pure TiO2, the XRD peak of SO42--modified TiO2 expands visibly. The surface free energy or surface diffusion coefficient may become small by the SO42--modification, which restraints surface shrinkage or ion aggregation. The effect of initial concentration of solution, TiO2 catalyst additive mass, materials of photocatalytic reactor on the degradation rate of Methylene blue were investigated in detail. The results indicated that when the mass concentration of nano-TiO2 is between 1.0 g/L and 1.5 g/L, Methylene blue(6～9 mg/L) can be degraded effectively using quartz pipes, and light source shows great influence on the decolorization rate. When the initial concentration of Methylene blue is 9 mg/L and the mass concentration of nano-TiO2 is 1.0 g/L, the solution color removal achieved 98.4 % in 2 hours irradiation at room temperature.At visible light, the solution color removal achieved 56.9 % in 16 hours irradiation at room temperature. The reaction of photo-catalysis for Methylene blue was not simple and is in conformity with the first order kinetics law in appearance with the concentration range between 6 mg/L and 15 mg/L. The appearance rate constant of the reaction decreased and half-life period of the reaction increase with increasing of initial concentration of Methylene blue in water, respectively. The present study showed that the ACF can be used as an adsorbent for the removal of Methylene blue from its wastewaters. The initial rate of adsorption of Methylene blue with ACF was high, then followed by a slower rate and gradually approached a plateau. The results of this research demonstrate that the Freundlich isothermal adsorption equation and pseudo-first-order kinetic model play significant roles in the adsorption of Methylene blue. Adsorption equation can be described as: q=99.7125[1-exp(-0.18177t)]. (C0=100 mg/L, room temperature). Thermodynamic activation parameters, such as , and were calculated with values of 106.294 KJ mol-1, -12.654 KJ mol-1和0.399 KJ mol-1 K-1, respectively. Loaded on ACF, the TiO2 particles were adsorbed in the groove of ACF, which secures both particle size and fixity. The problem that TiO2 particles are difficult to be recovered is resolved after TiO2 is loaded on ACF.