纳米纤维催化剂结合低温等离子体降解VOCs的研究

发布时间：2018-04-19 02:05

本文选题：挥发性有机物 + 静电纺丝　；参考：《浙江大学》2015年硕士论文

【摘要】：近年来,大气环境污染形势日益严峻,挥发性有机污染物(VOCs)作为其中最主要的污染物之一,不但具有致癌、致畸变的危害,部分VOCs甚至可形成光化学烟雾及PM2.5,造成二次污染。然而,VOCs的排放不但没有缓和之势,反而呈现总量逐年增加和成分越来越复杂的发展趋势,因而对其排放的控制已经刻不容缓。两段式低温等离子体结合催化技术(TPC)在处理较低浓度VOCs方面除了具有单独等离子体作用时流程短、易控制、适用范围广等优点外,还具有效率高、能耗较低、副产物较少等优势。但TPC系统所使用的传统催化剂在降解VOCs的活性和分解副产物的性能方面都存在限制。本文针对以上限制,结合静电纺丝的方法研制出了适用于两段式低温等离子体结合催化处理VOCs的高效纳米纤维催化剂,并且探究了有关纳米纤维催化剂性质活性等特征,研究了VOCs在仅有低温等离子体作用时和加入纳米纤维催化剂后的相关反应规律。第一章为本文的背景介绍及相关文献综述,首先介绍了VOCs的危害、排放趋势以及现有的处理技术。之后重点介绍了催化氧化降解VOCs的催化剂和用于制备纳米纤维催化剂的静电纺丝方法；低温等离子体的相关概念、产生及应用；低温等离子体结合催化剂技术在降解VOCs方面的研究和应用情况。最后针对现有两段式TPC系统中催化剂存在的问题提出了采用等离子体结合纳米纤维催化剂的方法进行对VOCs降解的研究思路。第二章是对实验中使用的材料及仪器,实验的装置及流程,测试方法做了较为详尽的说明。其中不但介绍了纳米纤维催化剂制备及降解VOCs实验装置、流程、表征方法及活性测试方法,也介绍了纳米纤维催化剂结合低温等离子体降解VOCs实验装置、流程、放电参数及副产物测试方法。第三章为纳米纤维催化剂对VOCs的降解相关研究。首先说明了不同Cu/(Cu+Ce)摩尔比的CuCeOx纳米纤维催化剂(NFs)的制备方法。然后对纳米纤维催化剂进行了SEM、EDX、TEM、XRD、XPS、H2-TPR和氮气吸附脱附表征研究以及活性测试。最后结合实验结果对纳米纤维催化剂对VOCs的催化反应机理进行了分析,结果表明优选出的Cu0.50-NFs纳米纤维催化剂具有高催化氧化丙酮活性的原因可归结为以下三点：第一,具有纳米级的纤维形貌和较大的比表面积；第二,具有丰富的氧空位；第三,具有较多的非常价态的过渡金属离子。第四章为两段式等离子体结合纳米纤维催化剂降解VOCs的研究。主要是将所制备的纳米纤维催化剂与低温等离子体技术通过TPC系统结合,分别测试仅有低温等离子体作用和加入纳米纤维催化剂后,放电峰值电压、初始浓度、能量密度等对VOCs降解的影响,并进行部分副产物分析,以探究低温等离子体结合纳米纤维催化剂技术对VOCs降解的性能以及反应机理。此外,还探究了在窗帘式DBD反应器中,较大气流量的情况下等离子体对VOCs降解的情况。第五章是全文总结及工作展望.包括对全文结论的总结归纳,论文创新点的提炼,以及对未来需要进一步加强或开展的研究工作的展望。
[Abstract]:In recent years, the atmospheric environment pollution situation is increasingly grim, volatile organic compounds (VOCs) as one of the main pollutants, not only has cancer, resulting in distortion of the harm, even some VOCs can form photochemical smog and PM2.5, cause two pollution. However, the emission of VOCs not only failed to ease the situation, instead of showing the total amount increased year by year the development trend and the increasingly complex components, thus to control its emissions is urgent. Two section low-temperature plasma combined with catalyst technology (TPC) in the treatment of low concentration of VOCs in plasma with a separate effect short process, easy control, wide application scope, but also has the advantages of high efficiency, low energy consumption. Fewer by-products and other advantages. But the traditional catalyst used in TPC system in the VOCs degradation activity and decomposition by-products are performance limitations exist. Based on the above restrictions,. Method of electrospinning developed efficient nano fiber catalyst used in the two section type low-temperature plasma combined with catalytic treatment of VOCs, and to explore the properties of nano fiber catalyst activity and other characteristics, studies the reaction rules in effect when only low temperature plasma and adding nano fiber catalyst after VOCs.
The first chapter is the introduction of the background and related literature review, firstly introduces the harmfulness of VOCs, emission trends and existing processing techniques. After introduced the catalytic oxidative degradation of VOCs and for the electrostatic spinning method for preparing nano fiber catalyst; low temperature from the sub body related concepts, research and production and application; application of low temperature plasma combined with catalyst technology in the degradation of VOCs. Finally put forward the research ideas on the degradation of VOCs by plasma method combined with nano fiber catalyst in the catalyst for the existing two segment TPC system.
The second chapter is about the materials and instruments used in the experiment, the experimental apparatus and process, test methods to do a more detailed explanation. Which not only introduces the nano fiber catalyst preparation and degradation of VOCs experimental device, process, method of test and characterization methods of activity, this paper introduces the combination of low temperature plasma degradation of VOCs experimental device, nano fiber catalyst process, by-products discharge parameters and test methods.
The third chapter is the research of nano fiber catalyst on the degradation of VOCs. The different Cu/ (Cu+Ce) CuCeOx nano fiber catalyst molar ratio (NFs) of the preparation method. Then the SEM of nano fiber catalyst EDX, TEM, XRD, XPS, H2-TPR and nitrogen adsorption desorption syndrome research and activity test. Finally, experimental results of nano fiber catalyst on the catalytic reaction of VOCs is analyzed. The results show that the optimized Cu0.50-NFs nano fiber catalyst with high catalytic oxidation of acetone activity can be attributed to the following three points: first, with nanometer fiber morphology and large specific surface area; second, with rich oxygen vacancies; third, transition metal ion valence has very more.
The fourth chapter is the study of nano fiber catalyst degradation of VOCs combined with two. Plasma is mainly prepared by nano fiber catalyst with low temperature plasma technology combined with TPC system were tested only in low temperature plasma and nano fiber catalyst, discharge peak voltage, initial concentration, influence of energy density on VOCs degradation. And analyze some by-products, to explore the low temperature plasma combined with nano fiber catalyst technology on VOCs degradation performance and reaction mechanism. In addition, it also explores the curtain in the DBD reactor, with air flow of the plasma on the degradation of VOCs.
The fifth chapter is the summary and Prospect of the work, including the summary of the conclusion, the refinement of the innovation, and the prospect of further research in the future.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;TQ426

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