【作者】 郭勇；

【导师】 陶长元； 陈洪；

【作者基本信息】 重庆大学 ， 环境工程， 2005， 硕士

【摘要】 超声波化学是化学、化工的一个新的分支。超声波作用能强化质量、热量传递和化学反应，提高过程速率。 据不完全统计，全国印染废水排放量约为每天300～400万吨。染料废水色度高、可生化性差、组分复杂，很难经济有效地用传统的废水处理方法进行处理。因此，针对染料废水的非常规处理的理论基础、方法和技术的研究，已成为人们所关注的热点问题之一。本文以典型的偶氮染料甲基橙为对象，开展了超声波促进Fenton法催化氧化降解甲基橙溶液的可行性研究。 论文较系统地研究了超声波促进Fenton法催化氧化降解甲基橙溶液的影响因素及其降解机理，研究工作表明： ①超声波与Fenton试剂联合作用降解甲基橙溶液时，能在较短的时间内使其中的大部分有机物矿化而脱色，而在超声波单独作用下则达不到相同的效果。这是因为超声空化效应在水中产生的·OH自由基的数量有限，而Fenton试剂在水中产生的大量的·OH自由基弥补了这一不足。 ②超声波促进Fenton法催化氧化降解甲基橙溶液时，硫酸根离子的生成规律与甲基橙的降解规律是一致的，但硫酸根离子的生成率明显小于甲基橙的脱色率。这说明甲基橙的催化降解反应可能是多步骤进行的，脱色反应处在较前步骤中，脱磺酸基反应处在较后步骤中，中间可能存在速率的控制步骤，从而影响脱磺酸基的速率，最终表现为甲基橙的脱色率大于硫酸根离子的生成率。 ③分别研究了超声波、Fenton试剂、超声波-Fenton试剂作用下甲基橙溶液的脱色和COD去除行为。结果表明，超声波单独作用于甲基橙溶时，几乎没有脱色效果；Fenton试剂单独作用于浓度为400mg／L的甲基橙溶液30min，甲基橙溶液色度去除率为67.51％，COD去除率为63.15％；而超声波和Fenton试剂共同作用时，甲基橙溶液色度去除率达86.91％，COD去除率达80.32％。超声波与Fenton试剂对甲基橙溶液的降解脱色和COD去除具有协同作用。Fenton试剂脱色强酸性甲基橙溶液是氧化反应，而在pH＞5时，是还原反应。通过紫外—可见光谱分析可知，甲基橙的最大吸收波长为490nm。更多还原

【Abstract】 Sonochemistry is a new branch of chemistry and chemical engineering. Ultrasound can intensify the process of mass transfer, heat transfer and chemical reaction, and can raise the rate of chemical process.Sonochemical oxidation makes use of cavitations phenomenon result from ultrasound. The formation, growth, and subsequent collapse of millions of microbubbles or cavities occur in extremely short intervah （micro-seconds）. In the process, large amount of energy is released. Cavitations can bring on generation of local hot spots, release of highly reactive free radicals, continuous cleaning as well as an increase in the surface area （resulting from fragmentation and deagglomeration） of the solid catalysts, and enhancement in the mass transfer rates attributed to turbulence generated by acoustic streaming.The discharge amount of dye waste water reported is as much as 3×10⁶ - 3×10⁶t³ /d. Dye waste water could not be treated effectively with traditional method for its deep color, poor biochemical degradation and complicated components. Therefore, worldwide attention has been paid on exploring novel techniques to degrade dye waste water.A new method to degrade dye waste water was studied in the current dissertation. For convenient, methyl orange （MO） solution was taken as a representative of dye waste water. MO degraded by Ultrasonic assistant Fenton was studied in the experiments. The main results were as following:（1） Degradation of MO was studied by different methods include Fenton reagent degradation, ultrasonic （US） degradation, ultrasonic-Fenton reagent degradation. The results showed that US/Fenton was the most efficient process for MO degradation. MO degradation could be promoted by ultrasonic. Effects of Fenton reagent amount, initial pH value and concentration of MO on MO degradation were also studied.（2） Study on degradation residue indicated that MO was degraded and the final product is H₂O, CO₂, NO₃^-, SO₄^2- and other non-degradable compounds.（3） By the methods of ultrasound, Fenton reagent and ultrasound-Fenton, performance and mechanism of decolorization and COD removal of methyl orange were investigated. Results indicated that with ultrasound solely, decolorization was low. When 400mg/L methyl orange solution was treated 30 min by Fenton reagent, the decolorization ratio and COD removal ratio were 67.51% and 63.15%. In the same operation conditions, the更多还原