共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
M Mahbubul Hassan Christopher J Hawkyard 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(2):201-207
The decolourisation of aqueous solutions of dyes by ozonation with various heterogeneous catalysts using a bubble‐column reactor was investigated. The catalysts studied were hydrated alumina, activated carbon and ferric oxide supported on silica. The optimum catalyst concentration and pH for decolourisation were determined in each case. Hydrated alumina and silica‐supported ferric oxide showed excellent catalytic activity under acidic conditions, whereas activated carbon was found to be effective under both acidic and alkaline conditions. In addition to studying the effect on individual dyes, tests were carried out on effluent from a commercial dyeing unit. The reaction kinetics in the presence of various catalysts were also monitored. Copyright © 2005 Society of Chemical Industry 相似文献
5.
Honeycomb-structured activated carbon (HAC) is one of the most studied chemicals with large specific surface area, high porosity, unique adsorption properties, and other characteristics, which has been widely used in the fields of exhaust gas adsorption, wastewater adsorption, and catalyst support. However, the study and application of HAC in the field of wastewater treatment is not extensive. Herein, a novel HAC-based bimetallic catalyst was prepared by incipient wetness co-impregnation, which exhibited high catalytic activity in heterogeneous catalytic ozonation of methylene blue (MB) organic wastewater. A high MB removal of 95.43% and a chemical oxygen demand (COD) removal of 85.19% were achieved by using Cu-La/HAC under optimized conditions. The inductively coupled plasma-mass spectrometry (ICP-MS) results showed that the metal dissolution concentration of Cu-La/HAC was the lowest. Moreover, X-ray photoelectron spectroscopy (XPS) characterization of copper-containing catalysts indicated that the strong interaction between copper and lanthanum resulted in the low metal dissolution concentration. 相似文献
6.
复合污泥基活性炭催化臭氧氧化降解水中罗丹明B 总被引:2,自引:0,他引:2
以污水处理厂生物污泥和化学污泥等为原料制备出复合污泥基活性炭(CAC),与纯生物污泥基活性炭(BAC)和商品活性炭(AC)对比,分别考察了吸附、催化臭氧氧化和自由基抑制剂存在时催化臭氧氧化对水中罗丹明B的去除效果,进而研究了p H和臭氧投加量对CAC催化效能的影响。结果表明,三种活性炭均能提高臭氧氧化降解罗丹明B的效率,CAC催化效能最好。CAC催化臭氧氧化罗丹明B的反应遵循羟基自由基机理,随着p H的增大和臭氧投加量增加,CAC催化效能得到提高。 相似文献
7.
水处理中的多相催化臭氧化技术 总被引:4,自引:0,他引:4
随着水质污染的日益严重,以产生大量自由基为主体的高级氧化技术越来越受到人们的关注。作为高级氧化技术的一种新形式,多相催化臭氧化将臭氧的氧化能力和催化剂的吸附性、催化作用更好地结合起来,对有机物的矿化程度更高。该文综述了该技术在水处理中的应用及其反应机理。 相似文献
8.
多相催化臭氧氧化法处理印染废水的研究 总被引:1,自引:0,他引:1
采用浸渍法制备了活性炭负载铁锰氧化物的催化剂用于对印染废水的多相催化臭氧氧化处理,当铁锰质量比为1∶2时,催化剂处理效果最佳。多相催化臭氧氧化工艺的最佳运行参数为:处理时间60 min、臭氧通气量0.2 L/min、催化剂投加质量20 g、废水pH=5。经多相催化臭氧氧化处理后,印染废水的COD、氨氮、TP、色度去除率分别为81.7%、90.2%、97.6%、99.1%,去除效果较好。 相似文献
9.
ACF催化臭氧化降解苯酚的反应参数影响 总被引:1,自引:0,他引:1
研究了活性碳纤维(ACF)催化臭氧化降解苯酚过程中各种参数的影响。结果表明,ACF能够显著提高臭氧化效率,当ACF为1g,反应10min时苯酚的去除率为96.8%,而同样条件下活性炭仅为68%;臭氧化效率在酸性下几乎相同并高于碱性下,而且在碱性下随pH值升高而降低;臭氧化空气流量从0.04m3/h增加到0.16m3/h,反应10min时的效率提高为17%;苯酚初始浓度升高到500mg/L仅使臭氧化效率下降不到10%。重复实验表明臭氧化过程中ACF的催化性能可以得到原位再生。 相似文献
10.
介绍了催化臭氧氧化的主要类别,分述了均相与非均相催化臭氧氧化在难降解石化废水方面的已有应用和催化机理,探讨了非均相催化臭氧氧化中活性炭的主要作用;简述了pH值、温度、臭氧和催化剂投加方式与投加量、催化剂体系等因素在非均相催化臭氧氧化中的影响规律。在已有研究的基础上,提出了将催化臭氧氧化与生化处理相结合的建议并佐证了其可行性;预测了催化臭氧氧化未来的研究方向;针对活性炭在催化臭氧氧化处理难降解石化废水中存在的问题,提出应加强对活性炭的改性研究,同时对某些工艺进行深入研究,全面掌握可能存在的问题,为完善催化臭氧氧化的机理作出努力。 相似文献
11.
12.
综述了Al2O3应用于非均相催化臭氧化体系的研究进展,对比了催化体系和单独臭氧体系对水中有机物的去除效果,从催化剂对有机物的吸附、溶液的pH值影响、溶液中存在的无机离子和臭氧的分解机理方面,探讨了影响Al2O3催化臭氧化体系催化效果的主要因素,分析了目前研究中存在的问题,展望了Al2O3催化剂在水处理方面的应用前景。 相似文献
13.
本文以哈尔滨煤化工有限公司污水处理厂的二级出水为研究对象,以粒状活性炭、壳状活性炭为主要实验材料,测定其对煤化工生化出水的处理效果。以活性炭和O3分别单独处理煤化工生化出水,以及应用O3-活性炭体系处理煤化工生化出水两部分进行试验研究。在分析各处理效果的同时,着重研究活性炭催化O3对煤化工生化出水的有机物降解效果。 相似文献
14.
15.
研究了不同浓度活性炭、活性焦和Mn2+催化作用下臭氧氧化污泥碳源释放情况,发现Mn2+为较佳催化剂。本文进一步对比考察了不同Mn2+投加量对催化臭氧化污泥溶胞释放有机物的影响以及反应前后污泥特性的差异,探究了Mn2+催化臭氧化促进溶胞作用的机理。结果表明,在臭氧氧化污泥时添加Mn2+能促进污泥碳源的释放,其中当Mn2+投加量为1.5mmol/L时,污泥碳源的释放效果较佳,溶解性化学需氧量的变化值(ΔSCOD)质量浓度为76mg/L,约为单独臭氧氧化(O3组)的4倍;污泥絮体胞外聚合物溶解性蛋白和腐殖质含量较原泥(空白组)和O3组相比均有显著增加,分别为2倍和2.3倍,证实了Mn2+催化氧化促进了活性污泥胞内有机物的溶出。进一步的机理探究得出,O3+Mn2+组·OH产量为O3组的1.15~1.74倍,说明Mn2+催化氧化促进了反应过程中活性自由基尤其是·OH的生成。Mn2+催化臭氧氧化活性污泥在强化污泥破胞的同时,对污泥的理化性质影响较小,基本与单独臭氧氧化维持在同一水平,后续将其应用于基于臭氧旁路处理的污泥原位减量连续工艺有较大的可行性和实际意义。 相似文献
16.
利用CeO_2的储氧和释氧能力,以高活性的活性炭作为催化剂载体,采用等体积浸渍法制备CeO_2-活性炭催化剂。分别用氮气低温吸附/脱附、XRD、XPS对CeO_2-活性炭催化剂进行表征。以CeO_2-活性炭作为催化剂,草酸作为模型化合物,催化臭氧化降解草酸的去除率达到77%。Ce组分的加入能显著提高草酸的去除率。Ce不仅能够提高反应体系中羟基自由基的浓度,还有利于O3分子直接氧化草酸。CeO_2-活性炭催化剂经过3次重复使用后,草酸去除率保持在70%以上,具有较好的稳定性。 相似文献
17.
18.
19.
20.
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