拟Fenton试剂处理罗丹明B废水的研究

实验研究了拟Fenton试剂氧化降解有机染料罗丹明B的脱色和COD去除情况.研究了初始溶液的pH值、H2O2用量、铸铁屑用量、初始染料浓度等因素对罗丹明B降解进程的影响,确定了方法的优化条件,并讨论了拟Fenton试剂的反应机理.实验结果表明,初始罗丹明B溶液pH值为3.0时,反应速度最快;针对500 mL的200 mg·L-1罗丹明B溶液的降解,30%的H2O2用量为2 mL,铸铁屑用量为0.2 g时,降解效率最好;拟Fenton试剂对高浓度的罗丹明B废水有较好的脱色效果和COD去除率.     

超声/过氧化氢联合降解苯酚废水的研究

采用超声波/过氧化氢(US/H2O2)工艺对苯酚模拟废水进行了降解,考察了处理时间、苯酚溶液的初始pH值、初始浓度、反应温度等对降解效果的影响.实验结果表明:在单一超声波辐照或过氧化氢氧化下苯酚的降解率低,而两者联合降解效果明显提高,表明存在协同效应.在苯酚废水初始浓度为50mg/L、初始pH值3.01、反应温度25℃、处理时间180min在US/H2O2共同作用下,苯酚降解率为52.2%.苯酚在US/H2O2工艺中的降解反应符合表观一级反应动力学.     

电Fenton法处理难降解废水的研究进展

用基于产生强氧化剂-羟基自由基的高级氧化技术处理难降解废水已成为近年来的研究热点,而高级氧化技术中的电Fenton法又以其独特的优点倍受人们的青睐.根据电生成Fenton试剂方法的不同,概括了电Fenton法的主要类型及其机理,介绍了各类型的优缺点及其在国内外的研究状况.同时,还介绍了电Fenton法与其它废水处理技术的联合工艺,对难降解废水具有很好的处理效果.最后,指出电Fenton法今后研究发展方向.     

硝基苯降解菌的筛选驯化及其最适降解条件研究

研究经过筛选、驯化、分离得到一硝基苯高效降解菌群,其对硝基苯废水的最佳降解条件为：厌氧,pH7～8,33～37℃,盐浓度为3．5～5．5g／L。该菌群不仅能耐受较低浓度的铬、铅等重金属离子,而且对二硝基甲苯也具有一定降解能力。硝基苯浓度为300mg/L,停留时间为20h时,硝基苯的去除率为95％;硝基苯浓度为500mg/L,停留时间为22h时,硝基苯去除率为82％。     

二氧化钛光催化降解硝基苯废水

用紫外灯作为光源,以锐钛型TiO2为催化剂降解硝基苯。探讨了光照时间、初始pH值、初始浓度、催化剂用量和载铜TiO2复合催化剂对光催化降解的影响。结果表明,TiO2用量为3.0 g/L,pH为3,硝基苯初始浓度为40.6 mg/L,室温条件下,光照6 h硝基苯降解率为80.6%;掺杂1%Cu2+(摩尔分数)的TiO2复合催化剂,光催化活性高于纯TiO2,其光催化降解率较TiO2提高14.5%。     

MW-GAC-H2O2降解水中微量硝基苯的动力学研究

采用MW-GAC-H2O2工艺(微波-活性炭颗粒-过氧化氢)降解水中微量硝基苯,研究了硝基苯初始质量浓度、pH、HCO3-和腐植酸对MW/GAC/H2O2降解硝基苯的动力学行为的影响。结果表明,硝基苯初始质量浓度越大,硝基苯降解速率越小;初始溶液pH为8时,硝基苯的降解速率最高;投加适量HCO3(-100～200mg/L)、腐植酸均可促进系统降解硝基苯。在硝基苯初始质量浓度为200μg/L、微波功率为300W、GAC和H2O2投加量分别为4g/L和10mg/L的试验条件下反应21min,MW-GAC-H2O2工艺降解硝基苯的速率为0.052 1 min-1,反应过程遵循1级反应动力学方程。     

KMnO4-O3协同氧化降解地下水中低含量硝基苯

利用高锰酸钾-臭氧(KMnO4-O3)体系的协同氧化作用处理地下水中低含量硝基苯(NB),研究了KMnO4-O3体系氧化降解NB的机理和效果,分析了O3和KMnO4的不同投加量和不同pH等因素对NB降解效果的影响,以及对O3和KMnO4-O3体系氧化除污染效能进行了比较.结果表明,KMnO4能促进O3分解产生大量羟基自由基(·OH)活性基团,从而使KMnO4-O3体系比单独O3对地下水中NB的去除率提高了约37个百分点.在氧化反应12min、pH=6.0、KMnO4和O3分别投加0.8和1.O mg·L-1时,KMnO4-O3体系氧化降解NB的去除率可达95%以上.该法处理工艺经济易行,不会产次生环境问题.     

硝基苯废水的TiO2光催化降解研究

以钛板负载TiO2光催化剂对水中的硝基苯的催化降解进行了研究,考察了催化反应时间、溶液的pH值等因素对光催化反应的影响.实验结果表明,在实验条件下,光催化降解硝基苯的最佳条件为pH=3,反应时间100 min.用H2O2 UV TiO2光催化反应体系处理低浓度的硝基苯样品效果更好一些.     

非均相类Fenton法降解硝基苯化工废水的效能及其机制

以实验室制备的3A-Fe型分子筛为催化剂,并利用扫描电镜、能谱分析和XRD技术对催化剂进行了表征。在3A-Fe型分子筛与H2O2构建的非均相类Fenton催化体系内对硝基苯的降解效能和机制进行了研究,讨论了体系pH值、H2O2的投加量、催化剂投加量、硝基苯废水浓度对硝基苯降解率和反应速率的影响,并初步揭示了硝基苯的降解机理。结果表明:3A-Fe分子筛作为催化剂的类Fenton反应,在pH值2~10之间都具有较好的处理效果;类Fenton体系氧化降解反应过程是一种非均相的界面微观反应;3A-Fe类Fenton催化剂性能优越,对硝基苯废水中硝基苯的去除率为94.1%,CODCr和TOC的去除率分别为78.6%和60.5%。     

铁粉和过氧化氢联合降解对氨基苯酚的研究

以铁粉作催化剂、H2O2作氧化剂去除废水中的对氨基苯酚(PAP),研究了初始pH值、H2O2加入量、铁粉加入量及反应时间对PAP去除率的影响.确定最佳去除条件如下:初始pH值7.0、H2O2加入量2.0 mL、铁粉加入量1.7 g、反应时间80 min,在此条件下,PAP去除率可迭93.6%.该法去除率高,不会带来二次...     

Degradation of halogenated organic compounds in ground water by heterogeneous catalytic oxidation with hydrogen peroxide

summary Catalytic oxidation with hydrogen peroxide is a reliable method for the treatment of polluted water. The conversion of a wide spectrum of components including aliphatic and aromatic hydrocarbons as well as halogenated organic compounds into non-toxic or minor-toxic substances and finally into carbon dioxide and water can be achieved. The degradation of chlorobenzene, 4-chlorophenol, 4-chloroaniline and 1-nitro-4-chlorobenzene was investigated. Several catalysts can be implemented into the catalytic process. It has been demonstrated that the type of catalyst and oxidation agent as well as the reaction parameters influence the degradation rate and has to be adjusted to the concrete waste water problem to be solved.     

用硫酸亚铁和过氧化氢混合体系处理丁苯橡胶生产废水

用硫酸亚铁和过氧化氢混合体系处理了丁苯橡胶生产废水，优化了工艺条件，进行了稳定性实验，并对处理前后的废水进行了水质分析．结果表明，不必调节废水的pH值、反应温度为55℃、Fe^2＋用量为200mg／L、H2O2用量为1000mg／L、反应时间为40min、加入氢氧化钙将氧化处理后废水的pH值调至中性进行絮凝、加入用量为1 mg／L的聚丙烯酰胺助凝，可显著降低废水中的铁离子质量浓度，提高化学需氧量去除率，同时废水的可生化性显著提高，为后续生物处理创造了良好的条件。     

The generation of hydroxyl radicals by hydrogen peroxide decomposition on FeOCl/SBA‐15 catalysts for phenol degradation

Iron oxychloride (FeOCl) supported on mesoporous silica (SBA‐15), as a Fenton‐like solid catalyst for phenol degradation, showed supreme activity for production of hydroxyl radical (HO·) by H₂O₂ decomposition, and the generation capacity was comparable to the conventional Fenton reagent (Fe²⁺+H₂O₂). The structure of FeOCl was characterized with spectroscopies. The generation of HO· species during the reaction was detected using 5,5‐dimethyl‐1‐pyrroline N‐oxide trapped electron paramagnetic resonance. Furthermore, the kinetics in detail was driven for the creation and diffusion of HO· by H₂O₂ decomposition over FeOCl, which follows a first‐order rate through a two‐step reaction. With the combination of the catalyst structure and kinetic parameters, the plausible mechanism for H₂O₂ decomposition during the oxidative degradation of phenol was rationalized. As a Fenton‐like solid catalyst, FeOCl/SBA‐15 is a promising alternative for the removal of low‐level organic contaminates from water. © 2014 American Institute of Chemical Engineers AIChE J, 61: 166–176, 2015     

Electrochemical ferrate generation for waste water treatment using cast irons with high silicon contents

This paper deals with the electrochemical preparation of ferrate in 15 M NaOH media, with a view to treatment of waste waters. Grey cast irons with high silicon contents were shown to allow current yields in the range 20–40% depending on the applied current density, up to 34 mA cm^–2. Ferrate solutions with contents up to 0.08 M could be produced in a divided cell of simple design, and provided with flat or packed-bed electrodes. Deactivation of the anode surface was shown to be of moderate significance for hour-long runs. The ferrate produced was tested for treatment of industrial liquid wastes: coagulation efficiency of the suspended matter was comparable with that of an electrocoagulation process with sacrificial Al anodes. The potential of waste water treatment by addition of ferrate is discussed.     

双氧水生产中的“三废”处理

探讨了蒽醌法双氧水生产过程中产生的废气、废水、废渣的处理方法。利用膨胀制冷联合炭纤维吸附技术对氧化尾气进行处理,同时也降低了芳烃的消耗;利用双氧水催化氧化-絮凝法对废水进行处理,处理后的水作为循环水系统的补充水,实现废水的再利用。     

Kinetics and mechanism of the reaction between ozone and hydrogen peroxide in aqueous solutions

A kinetic model has been developed, taking into account both decomposition of ozone molecules and interactions between ozone and hydrogen peroxide for formation of hydroxyl radical and subsequent reactions. Experiments were carried out at 25°C in the pH range of 3 to 13, indicating that the depletion rate of ozone increases with the concentrations of ozone, hydrogen peroxide and hydroxyl ion, as predicted by the kinetic model. Adverse scavenging reactions, however, also play significant roles at sufficient concentration ratios of hydrogen peroxide to ozone and high concentrations of hydroxyl ion in reducing the depletion rate. Results of this research suggest, that it is most desirable to conduct the peroxone oxidation for pollutant destruction by the hydroxyl radical reaction in alkaline solutions of pH below 11, while maintaining about the same concentration of ozone and hydrogen peroxide.     

铁盐+双氧水法处理铜冶炼酸性废水工艺改造实践

介绍了白银有色集团股份有限公司铜业公司酸性废水处理系统工艺流程及存在的问题。试验研究了铁盐+双氧水法药剂投加顺序、投加量、投加比例、pH值等因素对除砷效率的影响,在铁砷质量比为5～6、双氧水与铁盐加入比为1∶2.5左右时,具有较好的除砷效果,同时也具有较好的经济性。酸性废水处理系统技术改造后,处理后回用水砷含量指标稳定达标。     

过氧化氢脱硫工艺技术的研究

以过氧化氢为原料脱除硫酸尾气中的二氧化硫,研究过氧化氢浓度、反应温度、反应时间对脱硫率的影响,且对反应过程中过氧化氢的分解率进行了检测。实验结果表明:过氧化氢不足量时脱硫率随过氧化氢浓度的增加而增加,过氧化氢足量时过氧化氢浓度的改变对脱硫率影响不大;在实验条件下,过氧化氢分解率较低;反应温度对脱硫率影响不明显;在SO_2进气质量浓度为4 050 mg/m~3、进气量为0.25 m~3/h的条件下,最佳工艺条件为w(H_2O_2)0.25%、反应温度70℃、反应时间1 h,此条件下脱硫率为98%。     

高效液相色谱法测定水中硝基苯含量

采用反向高效液相色谱系统,建立了分析水中硝基苯含量的方法。方法采用C18色谱柱(250mm×4.6mm,5μm),甲醇∶水∶乙酸(70∶29∶1)为流动相,流速1.0mL.min-1,262nm为检测波长。结果表明,该方法准确、快速,回收率为99.0%~103.2%,相对偏差小于2.0%,线性范围0.0116~29mg.L-1,用上述方法分析实际水样结果令人满意。