【作者】 陆磊；

【导师】 冯贵颖；

【作者基本信息】 西北农林科技大学 ， 环境工程， 2010， 硕士

【摘要】 染料是一类具有稳定结构的有机物,在环境中可以长期滞留。染料废水中的一些物质对人体健康有严重的危害,人们已经在偶氮染料、蒽醌染料、三苯甲烷染料中发现了具有致突变性和致癌作用的物质。染料废水成分复杂,其中还含有铅、铬、锰等重金属离子,其进入水体后会影响水生动植物的生长。催化湿式过氧化氢氧化（CWPO）技术以H₂O₂作氧化剂,不仅可以使反应在常温常压下进行,而且分解产生的羟基自由基具有很强的氧化性,能氧化绝大多数有机物,且氧化速度较快,是目前处理难降解物质的重要方法之一。催化剂是催化湿式氧化法的关键,因此研究新型高效催化剂,对于催化湿式氧化法在难降解物质处理中的广泛应用具有重要的意义。本研究以酸性大红-3R模拟废水为处理对象,采用浸渍法制备负载型催化剂,探讨了负载型催化剂在CWPO工艺中对酸性大红-3R染料废水的催化降解活性,得出如下结论:1、制备的单一组分负载型CuO/γ-Al₂O₃催化剂,在催化反应3h后,酸性大红-3R的降解率为78.13%,铜流失量为8.53 mg·L^-1。循环使用3次后,其催化活性降低了35%。2、铈改性负载型CuO/CeO₂/γ-Al₂O₃催化剂相比于CuO/γ-Al₂O₃催化剂,在催化反应3h后,酸性大红-3R的降解率从78.13%增加到98.16%,铜流失量从8.53mg·L^-1降至2.76mg·L^-1。3、铈锆改性负载型Cu-Ce-Zr-O/γ-Al₂O₃复合氧化物催化剂相比于CuO/CeO₂/γ-Al₂O₃催化剂,表现出较高的活性和稳定性。在催化反应2h后,酸性大红-3R的降解率达到93.96%,铜流失量为0.12mg·L^-1,延长催化反应时间为3h时降解率达到96.26%,铜流失量未变。4、XRD表征结果说明,催化剂CuO/γ-Al₂O₃和Cu-Ce-Zr-O/γ-Al₂O₃中未出现CuO晶相和CuAl2O4尖晶石结构。对未改性催化剂CuO/γ-Al₂O₃而言,表明氧化铜物种在载体中呈高度分散状态。而催化剂Cu-Ce-Zr-O/γ-Al₂O₃相对于载体Ce-Zr-O/γ-Al₂O₃而言,随着铜元素的加入,铈锆固溶体的衍射峰有向大角度方向偏移的趋势,说明部分Cu进入铈锆固溶体形成Cu-Ce-Zr固溶体。5、选取Cu-Ce-Zr-O/γ-Al₂O₃催化剂,在催化湿式过氧化氢氧化（CWPO）法处理酸性大红-3R废水过程中,探讨温度、废水pH、过氧化氢和催化剂用量对降解效果的影响。研究结果表明:（1）温度对催化反应的影响比较明显,相同时间内温度越高其降解率越高。30℃和60℃时,催化反应0.5 h,酸性大红-3R的降解率分别为67.33%和95.52%。（2）随着pH的增加,酸性大红-3R的降解率呈现增大—基本不变—减小的变化趋势。在pH4～10范围内,催化剂表现出较高的催化活性,反映出改性催化剂Cu-Ce-Zr-O/γ-Al₂O₃有较好的酸碱适应性。（3）H₂O₂投加量小于10 g·L^-1时,酸性大红-3R的降解率随H₂O₂投加量的增大而增加。当H₂O₂投加量为6 g·L^-1,催化反应2h条件下降解率为93.96 %,继续增加H₂O₂的投加量,降解率仅增加了1.75%。所以H₂O₂的投加量为6 g·L^-1时已基本满足酸性大红-3R染料完全降解的需要。（4）随着催化剂用量的增加,酸性大红-3R的降解率升高。当催化剂用量增加至16.0 g·L^-1,催化反应2h条件下酸性大红-3R的降解率为93.96%;继续增加催化剂用量,酸性大红-3R的降解率基本不变。更多还原

【Abstract】 The dye is a kind of stable organic matter, which retaining in environment for a long time. Some matirials of dye wastewater are harmful to human health. Mutagenicity and carcinogenicity substances had been discovered in azo-dyes, anthraquinone dye and triphenylmethane dye. The dye wastewater ingredients are complex, which have influence on the aquatic zoology and botany growth after entering water body. It includes lead, chromium and manganese heavy metal ions. Catalytic wet peroxide oxidation （CWPO） is an important method to treat refractory compounds. Under normal temperatures and pressures, the method mainly relies on H₂O₂ as oxidant, which produce hydroxyl radicals with strong oxidizing property. In this way, majority of organic matter are easily oxidized with a higher oxidation rate. As the key of CWPO, catalyst is definitely important. So the research on new high-efficiency catalysts to treat difficult degradation matters with CWPO is imperative.The experimental take the acid scarlet-3R synthetic wastewater as the processing objects, and prepared supported catalyst by impregnation method. We discussed the degradation of supported catalyst to the acid scarlet-3R synthetic wastewater. The important results were as follow:1. The single component supported catalyst CuO/γ-Al₂O₃ was used to treat acid scarlet-3R. In this process, the degradation efficiency of acid scarlet-3R was 78.13%, the loss amount of copper was 8.53 mg·L^-1 as reaction time was 3h. The degradation activity decreased by 35% after recycles use of catalyst for three times.2. The Ce-modified on supported Catalyst CuO/CeO₂/γ-Al₂O₃ was also used to treat acid scarlet-3R. Compared with catalyst CuO/γ-Al₂O₃, the degradation efficiency of the latter raised form 78.13% to 98.16% as reaction time was 3h, while the loss amount of copper decreased from 8.53mg·L^-1 to 2.76 mg·L^-1。3. Composite oxide catalyst of cerium and zirconium was prepared to treat acid scarlet-3R. Compared with catalyst CuO/CeO₂/γ-Al₂O₃, Catalyst CuO/CeO₂/γ-Al₂O₃ had higher activity and stability. With the loss amount of copper was 0.12 mg·L^-1, the degradation efficiency of acid scarlet-3R reached 93.96% in two hours, whereas the degradation efficiency was up to 96.26% in three hours.4. The XRD characterization results concluded that there weren’t crystalline phase of CuO and CuAl2O4 spinel structure for catalyst CuO/γ-Al₂O₃ and Cu-Ce-Zr-O/γ-Al₂O₃. This showed highly dispersed copper oxide on vector for catalyst CuO/γ-Al₂O₃. Compared Cu-Ce-Zr-O/γ-Al₂O₃ with Ce-Zr-O/γ-Al₂O₃, diffraction peak position of Ceria-Zirconia solid solution shifted a large angle with the addiction of copper, which indicated Cu-Ce-Zr solid solution has formed through entering Cu into Ce-Zr solid solution.5. We choose Cu-Ce-Zr-O/γ-Al₂O₃ catalyst to treat acid scarlet-3R synthetic wastewater by CWPO and investigate the effect of temperature, wastewater pH, H₂O₂ and catalyst dosage on degradation effectiveness. The results showed:（1） Temperature had obvious influence on catalyst reaction. Degradation rate increased as temperature increased in the same time. When the temperature was 30℃and 60℃, as well as catalyst reaction time was 0.5h, The Degradation rate of acid scarlet-3R were 67.33% and 95.52%.（2） Acid scarlet-3R degradation rate increased and then decreased as pH increased. Catalyst had higher catalytic activity when pH varies from 4 to 10, which showed that the modified catalyst had better acid-base suitability.（3） When H₂O₂ dosage less than 10 g·L^-1, acid scarlet-3R degradation rate increased as H₂O₂ dosage increased. The degradation rate reached 93.96% as H₂O₂ dosage was 6 g·L^-1 and reaction time was 2h. The optimal dosage of H₂O₂ was 6 g·L^-1.（4） Acid scarlet-3R degradation rate increased as catalyst dosage increased. Acid scarlet-3R degradation rate reached 93.96% as catalyst dosage was 16.0 g·L^-1 and reaction time was 2h.更多还原