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超声-光催化降解水中有机污染物 总被引:4,自引:0,他引:4
超声-光催化是一项近年发展起来的废水处理的新型高级氧化技术。该技术利用超声的空化效应、自由基效应以及机械效应强化光催化的催化效能,实现超声和光催化对水中有机污染物的协同降解。本文从水中有机污染物的超声-光催化降解机理、降解动力学、影响因素(光催化剂类型和投加量、超声频率和强度、溶液pH值、温度、反应物初始浓度、溶解性气体和离子强度)和反应器类型(悬浮型、固定床型)4个方面介绍了相关研究进展,提出了目前存在的主要问题,并展望了超声-光催化降解水中有机污染物的发展方向。 相似文献
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LI Xin YAO Jun-hai QI Jing-yao 《高等学校化学研究》2007,23(3):273-275
Different series of transition metal catalysts supported on Al2O3 were prepared by the impregnation method. The catalytic activity was measured in a batch reactor with ozone as the oxidizing reagent. The experimental results indicate that Cu/Al2O3 has a very effective catalytic activity during the ozonation of organic pollutants in water. The optimum conditions for preparing Cu/Al2O3 were systematically investigated with the orthogonal testing method. Furthermore, the results also show that the surface properties of catalyst are not compulsory for effective oxidation. 相似文献
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活性炭(AC)能够催化过氧化氢(H2O2)释放出强氧化性的羟基自由基•OH。过二硫酸盐(PS)与H2O2结构上相似,因此PS也有可能被AC催化产生强氧化性的硫酸根自由基SO4−•。AC催化无机过氧化物(H2O2或PS)将发展成为一类新型高级氧化技术。AC催化H2O2联合体系包括AC/H2O2,AC/Fenton,AC/H2O2/紫外光,,AC/H2O2/微波,AC/湿式H2O2氧化;AC催化AC/PS联合体系包括 AC/PS,AC/PS/金属离子, AC/PS/ 微波。AC过氧化联合体均可高效降解水中有机污染物。本文在首次综述AC/过氧化物联合体系处理有机污染物研究现状的基础上,分析了AC和过氧化物的相互作用,并对该类高级氧化技术的发展前景进行了展望。 相似文献
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漆酶是一种含铜的多酚氧化酶, 属于铜蓝氧化酶蛋白, 能催化氧化多种难降解的有机污染物。漆酶催化氧化水中有机污染物具有底物广泛、能耗低、易操作、环境友好等优点,是一项前景广阔的生物处理技术。本文综述了漆酶对水中有机污染物的催化降解,主要从漆酶的化学组成、结构、催化降解机理、漆酶的固定化、影响因素(溶液pH值、温度、金属离子、营养因子、有机溶剂、漆酶的浓度、底物的初始浓度等)、降解的动力学以及漆酶在处理水中有机污染物的应用等五个方面介绍了相关的研究进展。漆酶催化氧化有机物的机理主要表现在底物自由基中间体的产生和氧气还原成水两个方面。本文提出了目前漆酶催化氧化水中有机污染物存在的主要问题,并展望了漆酶降解水体中有机污染物的发展方向。 相似文献
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These days, explorations have focused on designing two-dimensional (2D) nanomaterials with useful (photo)catalytic and environmental applications. Among them, MXene-based composites have garnered great attention owing to their unique optical, mechanical, thermal, chemical, and electronic properties. Various MXene-based photocatalysts have been inventively constructed for a variety of photocatalytic applications ranging from pollutant degradation to hydrogen evolution. They can be applied as co-catalysts in combination with assorted common photocatalysts such as metal sulfide, metal oxides, metal–organic frameworks, graphene, and graphitic carbon nitride to enhance the function of photocatalytic removal of organic/pharmaceutical pollutants, nitrogen fixation, photocatalytic hydrogen evolution, and carbon dioxide conversion, among others. High electrical conductivity, robust photothermal effects, large surface area, hydrophilicity, and abundant surface functional groups of MXenes render them as attractive candidates for photocatalytic removal of pollutants as well as improvement of photocatalytic performance of semiconductor catalysts. Herein, the most recent developments in photocatalytic degradation of organic and pharmaceutical pollutants using MXene-based composites are deliberated, with a focus on important challenges and future perspectives; techniques for fabrication of these photocatalysts are also covered. 相似文献
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Ming Hua ZHOU Zu Cheng WU* Da Hui WANG Department of Environmental Science Engineering Zhejiang University Hangzhou 《中国化学快报》2001,(10)
As typical contaminants, phenolic pollutants are wide spread and are toxic to aquatic life. Thus the demand for new technology to remove or detoxify such organics should be widely recognized. Recently, electrochemical method has attracted a great deal of attention for treating such kinds of wastewater, mainly because of its amenability to automation, high efficiency and environmental compatibility1. Various electrochemical processes have been developed and anodic oxidation might be the most w… 相似文献
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XU Gen-Liang 《高等学校化学学报》1999,20(Z1):266
There are many noxious, harmful and difficulty biological resolved pollutants in dye waste water which will harm the water environment if it is drained off directly. Analyzing compositions and contents of organic pollutants in dye waste water is the important basis to define the control and harness technology of waste water. In this study, reverse phase high performance liquid chromatography was used to analyze quantitatively waste water of nitrify and reduction stages of 3-Amino-4-methoxyl aniline、waste water of 2, 6- DichIoro-4-nitro-aniline and waste water at upper reaches and below reaches of factory general waste drains in dye chemical plants. 相似文献
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Dr. Kojiro Fuku Honami Kanai Masanobu Todoroki Nanako Mishima Taisei Akagi Dr. Takashi Kamegawa Prof. Naoki Ikenaga 《化学:亚洲杂志》2021,16(14):1887-1892
Water pollution derived from organic pollutants is one of the global environmental problems. The Fenton reaction using Fe2+ as a homogeneous catalyst has been known as one of clean methods for oxidative degradation of organic pollutants. Here, a layered double hydroxide (Fe2+Al3+-LDH) containing Fe2+ and Al3+ in the structure was used to develop a “heterogeneous” Fenton catalyst capable of mineralizing organic pollutants. We found that sulfate ion (SO42−) immobilized on the Fe2+Al3+-LDH significantly facilitated oxidative degradation (mineralization) of phenol as a model compound of water pollutants to carbon dioxide (CO2) in a heterogeneous Fenton process. The phenol conversion and mineralization efficiency to CO2 reached >99% and ca. 50%, respectively, even with a reaction time of only 60 min. 相似文献
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我国废水排放总量较大,且废水中含有的多种有机污染物一直是人类生命健康的潜在威胁,因此对废水处理的研究必不可少,而理解废水中有机污染物的降解机理是处理各种废水的基础.本综述概述了国内外针对各种有机污染物降解机理的研究方法,主要包括实验手段和计算模拟两大类.实验手段中主要采用光谱分析技术检测有机污染物降解过程中生成的中间产物,进而推测有机污染物的降解路径.但是由于实验条件和实验方法的不同,对于同种物质的降解机理研究,不同的实验结果存在着争议.基于量子化学计算、定量构效关系模型(QSAR)、定量结构-生物降解性能关系模型(QSBR)、统计分子碎化模型(SMF)等计算模拟方法为有机污染物降解机理的研究提供了新的方法.将实验手段和计算模拟有机结合起来,可为有机污染物的降解机理研究提供参考和指导. 相似文献
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TiO2/膨润土光催化降解有机污染物 总被引:9,自引:0,他引:9
用溶胶-凝胶法制备了一系列TiO2/膨润土光催化剂(不同负载量和不同焙烧温度), 以罗丹明B(RhB)为模型化合物, 通过测定染料吸光度和体系化学需氧量(COD)变化, 来研究它们在紫外光照射下降解有机污染物的性能. 评价结果表明, 负载量为50%和焙烧温度为400 ℃的催化剂Ti400样品降解RhB活性较好, 虽然其矿化活性略小于P25(光照4 h P25的COD变化为99.7%, 400 ℃焙烧的TiO2/膨润土催化剂Ti400的COD变化为97.0%), 但是TiO2/膨润土催化剂更易于回收再利用. 用Ti400做催化剂降解RhB, 连续循环使用7次, 其催化活性基本不变. 用XRD、BET和紫外可见漫反射(UV-Vis DRS)等方法对这些催化剂进行了表征. 表征结果表明催化剂比表面积大有利于催化活性的提高. 相似文献
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挥发性有机污染物的光催化氧化(PCO)过程反应动力学多数符合L-H模型。本文综述了近年来在L-H模型基础上提出的改进的动力学模型的研究进展。除流速、污染物的初始浓度外,光强度、相对湿度、反应器系数、对流传质系数、电子-空穴对的结合速率以及中间产物等因素对PCO反应同样起不可忽略的作用;分析了通过反应动力学模型判断光催化反应速率控制步骤的方法;总结了适用于L-H模型的实验条件如反应器类型、催化剂、光源、污染物类型等。 相似文献
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Wenzheng Liu Qiang zhao Tahan Wang Xiaoxia Duan Chuanhui Li Xiao Lei 《Plasma Chemistry and Plasma Processing》2016,36(4):1011-1020
A method of plasma treatment in which a glow discharge was generated in the small gas gap between an electrode and a water surface was designed and employed in this study. By using this method, many active species were generated on the wastewater surface to degrade organic pollutants. The electric field distribution of the designed electrode model was simulated using the MAXWELL 3D® simulation software, and the discharge parameters were measured to investigate the impact of design optimization. In addition, we designed an equipotential multi-electrode configuration to treat a methyl orange solution and an azobenzene solution. The experimental and simulation results indicate that the designed electrodes can realize glow discharge with a relatively low voltage and that the generated plasma covers a large area and is in a stable state. Accordingly, the method helped reduce the cost of the reactor and improved the effectiveness of wastewater treatment. 相似文献
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新型双功能复合电极的制备及其加速水中有机污染物降解作用的研究 总被引:1,自引:0,他引:1
介绍了新型复合电极的制备方法、其双功能特性以及在提高水中有机污染物(如苯胺)降解速度所起的作用,并对其作用机制进行了讨论.实验结果表明,由空气电极和TiO2光催化剂组成的复合电极,当其工作电位控制在0.05V(vs.SCE)左右时,既具有良好的光电效应,又具有以较高效率合成H2O2的特性,使溶液中的有机分子获得来自光催化氧化与光化学氧化两方面的联合降解作用,从而显著地提高了有机分子的氧化降解速度. 相似文献