共查询到17条相似文献,搜索用时 78 毫秒
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采用微波强化催化湿式H_2O_2氧化法降解喹啉,以负载型Cu-Ce/γ-Al2O3/TiO_2为催化剂,考察了微波功率、反应温度、H_2O_2投加量和溶液初始p H对降解效果的影响。实验结果表明,在喹啉初始质量浓度为100 mg/L、微波功率为500 W、反应温度为60℃、pH=6、H_2O_2投加量为0.094 mol/L的条件下,反应18 min后,喹啉和TOC去除率分别可达100%、82.18%。微波可明显提高反应速率,反应体系中喹啉降解和H_2O_2分解均符合一级动力学。 相似文献
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在非催化条件下,H2O2可以有效地对淀粉进行氧化降解。H2O2用量由2 mL增加至12 mL的过程中,淀粉的粘度下降百分率由3.49%增加至57.91%,继续增加H2O2的用量,淀粉的粘度下降百分率不再明显变化。对降解时间的研究表明,最佳反应时间为120 min,延长反应时间,淀粉的粘度反而有所增加。在18~70℃的范围内,H2O2对淀粉的氧化降解性能先增加后减弱,在60℃时达到最好,淀粉的粘度下降百分率为52.36%。在H2O2的作用下,淀粉中羟基部分被氧化为羧基或醛基,另外淀粉分子链中的1,4位的环间苷键也可能被打断,从而使淀粉的粘度下降。 相似文献
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湿式氧化-催化湿式氧化联用处理定影废水 总被引:1,自引:0,他引:1
采用湿式氧化(WAO)-催化湿式氧化(CWAO)两段工艺处理定影废水,重点考察了反应时间、温度、压力、pH等因素对WAO处理效果的影响,并进行了CWAO处理WAO出水氨氮的尝试,取得了较好的效果.实验确定WAO适宜的反应条件:温度为160℃、氧分压为1 MPa、反应时间为2 h、进水pH为4.8.该条件下的CODCr去除率达79%,出水pH为1.4.CWAO处理WAO出水时所选定的反应条件:pH为12.9、温度为250℃、氧分压为3 MPa、反应时间为2 h.采用CWAO和WAO联用的方法处理定影废水,CODCr去除率达99.8%,氨氮去除率达97.8%,pH为5.6. 相似文献
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以过渡金属氧化物CuO为主活性组分通过对Cr2O3的复合和掺入电子助剂La2O3的考察,研制出适用于催化湿式氧化处理山梨酸生产废水的复合催化剂。考察了各组分浸渍液浓度、焙烧温度和焙烧时间等制备条件对催化剂的催化活性和稳定性的影响,确定了最佳制备条件。结果表明:优化制备的CuO-Cr2O3-La2O3/TiO2催化剂,用于处理山梨酸生产废水时具有良好的催化活性和稳定性,在θ=220℃,p(O2)=2.5 MPa,反应时间t=120 min,山梨酸生产废水初始CODCr=10 030 mg/L条件下CODCr去除率达到96.6%,而在相同条件下未加催化剂的湿式氧化CODCr去除率只有60.8%。 相似文献
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催化湿式氧化法是一种有效的处理有毒、有害、高浓度有机废水的水处理技术。文章对催化湿式氧化技术的机理、催化剂的组成、分类、特点、主要技术指标、参数及目前的应用等情况做了介绍。指出催化剂的加入能够极大的提高湿式氧化技术对有机物的降解效率,高效、稳定的催化剂的研制是降低湿式氧化反应温度与压力的有效手段。催化湿式氧化技术是较有发展前途的水处理技术。 相似文献
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采用浸渍法制备了负载型铜铁氧化物催化剂,并以喹啉为目标污染物,建立了湿式过氧化氢催化氧化(CWPO)体系.研究了反应温度、初始pH、H2O2和催化剂投加量对喹啉去除效果的影响,并分析了CWPO体系中 的作用及喹啉的降解路径.结果表明,CWPO对喹啉具有很好的去除效果,反应30 min喹啉的去除率可达到100%,反应60 min矿化率可达到88.34%.确定了最佳反应温度为80℃,初始pH为7,H2O2和催化剂投加量分别为29.15 mmol·L-1和4 g·L-1. 氧化在CWPO降解喹啉体系中起主导作用,其平均产生速率为1.69×10-6 mmol·L-1·min-1.推测了CWPO降解喹啉的4种可能路径,在中性和酸性条件下,分别生成以吡啶环或苯环为主的中间产物. 相似文献
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以自制Fe2O3-Ce O2/γ-Al2O3为催化剂,采用催化湿式过氧化氢氧化法(CWPO)预处理有机磷农药废水,通过单因素和正交试验研究了过氧化氢投加量、起始p H、反应温度和反应时间对COD的去除效果及影响规律。结果表明,反应最优条件为H2O2投加量2 m L、起始p H=5、反应温度80℃、反应时间40 min,在此条件下COD的去除率可达85.8%,可生化性提高到B/C=0.43。运用一级动力学模型和Arrhenius经验公式,建立了催化湿式过氧化氢氧化降解COD的动力学方程。 相似文献
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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. 相似文献
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Fernando Martínez M. Isabel Pariente Juan Ángel Botas Juan Antonio Melero Alicia Rubalcaba 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(7):880-886
BACKGROUND: Iron species were heterogeneously supported over activated carbons (AC) after different oxidizing pre‐treatments. The influence of the oxidizing method on the iron yield and the physicochemical properties of the iron‐containing activated carbons (Fe/AC) were studied. Thereafter, the activity and stability of Fe/AC catalysts for the wet peroxide oxidation of phenol as model pollutant was evaluated. RESULTS: The pre‐oxidizing treatment with HNO3 was the most appropriate for iron incorporation, providing a Fe/AC catalyst with the highest TOC removal and oxidant efficiency. A high stability of the catalysts was observed with low values of iron leaching (below 1.5% of their initial iron contents). The best Fe/AC catalyst was studied at different reaction temperatures and initial phenol concentrations. CONCLUSION: The promising results for the Fe/AC catalyst using HNO3 pre‐oxidizing treatment lay in the remarkable adsorption capacity of the carbon matrix and the potential activity of the iron species as Fenton‐like catalyst for the generation of oxidizing hydroxyl radicals. Copyright © 2012 Society of Chemical Industry 相似文献
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F Javier Rivas Stan T Kolaczkowski Fernando J Beltran David B McLurgh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1999,74(5):390-398
The promoted wet air oxidation of phenol has been investigated through the addition of hydrogen peroxide as a source of free radicals. The reaction has been shown to proceed in two stages, an initial fast reaction associated with hydrogen peroxide consumption and a second slower step that occurs at a rate comparable with conventional wet air oxidation. An increase in temperature has a positive effect on both stages, while oxygen partial pressure only influences the second slower stage. The influence of pH on phenol oxidation is shown to be significant with the highest efficiency achieved at very alkaline conditions when phenol is completely dissociated. The catalytic activity of homogeneous metal salts was investigated in both the presence and absence of hydrogen peroxide. The combined addition of hydrogen peroxide and a bivalent metal (ie copper, cobalt or manganese) is shown to enhance the rate of phenol removal. However, in the absence of hydrogen peroxide only copper exhibited catalytic activity. Finally, a reaction mechanism involving different radical species has been proposed. From the experimental results the apparent activation energy (96.9 ± 3.5 kJ mol−1) and pre‐exponential factor (1.6 ± 0.2 1010 s−1) were calculated for hydrogen peroxide decomposition into hydroxyl radicals. © 1999 Society of Chemical Industry 相似文献
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