摘 要
制药废水中抗生素的残留对生态环境和人类健康构成了潜在威胁，而传统处理方法难以有效去除这些微量污染物。本研究以纳米TiO₂光催化技术为核心，探讨其在降解制药废水中抗生素方面的效能与机理。通过对比不同催化剂负载量、光照条件及反应时间下的降解效率，揭示了纳米TiO₂在紫外光照射下产生的活性氧物种（如·OH和O₂⁻）对抗生素分子的氧化作用机制。实验采用罗红霉素作为目标污染物，利用高效液相色谱法（HPLC）监测降解过程，并结合自由基捕获实验验证活性物质的作用。结果表明，在最佳条件下（催化剂浓度为0.5 g/L，pH值为3），罗红霉素的降解率可达92%以上，且矿化程度显著提高。此外，通过中间产物的鉴定与分析，进一步明确了抗生素分子的降解路径，发现主要涉及羟基化、脱乙酰基和环裂解等反应步骤。本研究创新性地引入表面改性纳米TiO₂以增强其光催化性能，结果显示改性后的催化剂具有更高的比表面积和更强的光吸收能力，从而显著提升了降解效率。同时，研究还评估了实际废水中的共存物质对光催化反应的影响，发现有机物竞争效应和无机离子抑制作用是影响降解效率的关键因素。最终得出结论，纳米TiO₂光催化技术是一种高效、环保的抗生素去除方法，其在实际应用中具有广阔前景，但需针对复杂废水体系优化工艺参数。本研究不仅为制药废水处理提供了新思路，还为深入理解光催化降解抗生素的机理奠定了理论基础。关键词：纳米TiO₂；光催化降解；抗生素；罗红霉素；表面改性
Abstract
The residual antibiotics in pharmaceutical wastewater pose potential threats to ecological environments and human health, while traditional treatment methods struggle to effectively remove these trace pollutants. This study focuses on the efficacy and mechanism of nano-TiO₂ photocatalysis in degrading antibiotics in pharmaceutical wastewater. By comparing degradation efficiencies under varying conditions such as different catalyst loadings, light exposure, and reaction times, the study elucidates the oxidation mechanisms of reactive oxygen species (e.g., ·OH and O₂⁻) generated by nano-TiO₂ under ultraviolet irradiation on antibiotic molecules. Erythromycin was selected as the target pollutant, and its degradation process was monitored using high-performance liquid chromatography (HPLC), with radical scavenging experiments conducted to validate the role of active species. The results indicate that under optimal conditions (catalyst concentration of 0.5 g/L and pH of 3), the degradation rate of erythromycin can exceed 92%, accompanied by a significant increase in mineralization. Furthermore, through the identification and analysis of intermediate products, the degradation pathway of antibiotic molecules was clarified, revealing key reactions including hydroxylation, deacetylation, and ring cleavage. Innovatively, this study introduced surface-modified nano-TiO₂ to enhance photocatalytic performance, demonstrating that the modified catalyst exhibits a higher specific surface area and stronger light absorption capability, thereby significantly improving degradation efficiency. Additionally, the influence of coexisting substances in real wastewater on photocatalytic reactions was evaluated, identifying organic competition effects and inorganic ion inhibition as critical factors affecting degradation efficiency. In conclusion, nano-TiO₂ photocatalysis is an efficient and environmentally friendly method for removing antibiotics, showing promising prospects for practical applications, though process parameters need optimization for complex wastewater systems. This study not only provides new insights into pharmaceutical wastewater treatment but also establishes a theoretical foundation for a deeper understanding of the photocatalytic degradation mechanisms of antibiotics..
Key Words：Nano TiO₂；Photocatalytic Degradation；Antibiotics；Roxithromycin；Surface Modification
目 录
摘 要 I
Abstract II
第1章 绪论 2
1.1 研究背景与意义 2
1.2 纳米TiO₂光催化降解抗生素的研究 2
1.3 本文研究方法与技术路线 3
第2章 纳米TiO₂光催化降解抗生素的效能评估 4
2.1 光催化降解效能的影响因素分析 4
2.2 不同纳米TiO₂材料的对比研究 4
2.3 抗生素降解效率的实验验证 5
2.4 效能评估结果与讨论 6
第3章 纳米TiO₂光催化反应机理分析 7
3.1 光催化反应的基本原理 7
3.1.1 光生电子-空穴对的生成 7
3.1.2 活性自由基的产生机制 7
3.1.3 表面反应过程解析 8
3.1.4 能量转化效率分析 8
3.2 抗生素分子的降解路径 8
3.2.1 分子结构特征分析 9
3.2.2 中间产物的检测与鉴定 9
3.2.3 降解路径的理论模拟 10
3.2.4 实验验证与数据分析 10
3.3 影响机理的关键参数 10
3.3.1 pH值对反应过程的影响 11
3.3.2 温度变化的作用机制 11
3.3.3 光照强度的调控效应 11
3.3.4 催化剂负载量的优化 12
第4章 纳米TiO₂改性及其对抗生素降解性能的影响 13
4.1 改性纳米TiO₂材料的制备方法 13
4.1.1 掺杂元素的选择与作用 13
4.1.2 表面修饰技术的应用 13
4.1.3 材料形貌与结构表征 14
4.1.4 制备工艺的优化策略 14
4.2 改性对光催化活性的提升机制 14
4.2.1 电子-空穴分离效率的改善 15
4.2.2 活性位点数量的增加 15
4.2.3 吸收光谱范围的扩展 16
4.2.4 实验验证与性能对比 16
4.3 改性材料在实际废水中的应用效果 16
4.3.1 制药废水成分分析 17
4.3.2 实际废水处理实验设计 17
4.3.3 处理效果评价指标 17
4.3.4 结果分析与问题探讨 18
结 论 18
参考文献 20
致 谢 21
