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磷酸活化植物基活性炭对水溶液中铅的吸附 总被引:2,自引:1,他引:2
以棉秆与互花米草为原料,采用磷酸活化法制备了低成本的植物基活性炭,通过静态实验研究了其对重金属铅的吸附性能。结果表明,在活化温度为500℃、活化时间为2 h条件下,制备的棉秆和互花米草活性炭比表面积为1 570m2/g和856 m2/g,含氧酸官能团含量分别为1.43 mmol/g和1.27 mmol/g。在25℃下,两种活性炭对重金属铅的Langmuir最大吸附量分别为119 mg/g和111 mg/g,吸附最佳pH为4.3,吸附平衡符合Freundlich方程,离子交换在吸附过程中发挥了重要作用。 相似文献
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剩余污泥制备活性炭及其应用研究 总被引:3,自引:3,他引:3
以城市污水处理厂二沉池排出的剩余污泥为原料,采用不同活化方法制备活性炭,同时对比活化效果,研究了制备工艺条件对污泥活性炭吸附性能及产率的影响。结合比表面积、孔径分布和扫描电镜表征分析,对制备的污泥活性炭的性能进行评价,并探讨了污泥活性炭作为水处理吸附剂的去除效果。结果表明,以ZnCl2为活化剂制备的活性炭性能较好,其最佳制备条件为:活化温度550℃,活化时间45 min,ZnCl2浓度40%,固液比1∶2。制得的污泥活性炭的碘吸附值为496 mg/g,产率为51.8%,比表面积为301.4 m2/g,孔体积为0.37 mL/g,微孔体积为0.08 mL/g,平均孔径为5.78 nm。将该产品用于处理城市污水,投加量为0.8%,吸附平衡时间约为60 min时,对COD的去除率为81%,吸附容量为42.53 mg/g。 相似文献
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稻壳基活性炭制备及其对重金属吸附研究 总被引:6,自引:0,他引:6
活性炭吸附法是重金属废水处理的重要方法.利用廉价的稻壳,选择氢氧化钠和磷酸作活化剂制备活性炭,测定了稻壳基活性炭的比表面积、亚甲基蓝吸附值、碘吸附值、苯酚吸附值和等电点.利用制备的稻壳基活性炭吸附溶液中的Cd、Cu、Zn,研究了不同稻壳基活性炭对Cd、Cu,Zn的吸附差异,并利用X射线衍射仪分析了稻壳基活性炭中微晶体结... 相似文献
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Fenton法制备污泥基活性炭及其性能表征 总被引:1,自引:0,他引:1
污泥基活性炭孔隙率低下是污泥资源化利用的主要制约因素,而Fenton法预处理污泥,可有效改善活性炭性质。通过考察H2O2投加量、H2O2/Fe2+、活化pH以及炭化条件等参数,确定了最佳污泥基活性炭制备条件:H2O2投加量为5%(质量分数),H2O2/Fe2+为5∶1(质量比),活化pH为3,活化时间为2.0h,污泥含固率为1.0%(质量分数),炭化温度为600℃,炭化时间为2.0h,炭化升温速率为10℃/min。此时,得到的污泥基活性炭吸附碘值为340mg/g,比表面积为353.563m2/g,孔容积为0.238cm3/g,微孔容积为0.095cm3/g。该活性炭对阳离子和阴离子染料(亚甲基蓝和甲基橙)具有良好的吸附性能,结果表明,对亚甲基蓝和甲基橙的吸附更符合Langmuir方程,且其饱和吸附量分别为71.53、57.73mg/g。对吸附动力学的拟合结果表明,该吸附更符合二级动力学方程。 相似文献
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以(NH4)2HPO4活化沙柳纤维制备活性炭纤维,L16(45)正交实验优化制备工艺条件,重点研究了活化温度对活性炭纤维结构的影响。同时应用扫描电镜(SEM)对其表面形貌进行表征,通过N2吸附-脱附测定其孔结构。结果表明,随着活化温度的升高,活性炭得率逐渐减小,碘吸附值先增大后减小,在浸渍比2.5:1、预氧化温度200℃、预氧化时间90 min、活化温度为800℃、活化时间60 min的条件下,可以制备出比表面积为1 304 m2·g-1、总孔容为1.004 cm3·g-1、得率为31.6%、碘吸附值为1 321 mg·g-1的纤维状活性炭。 相似文献
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生物质活性炭的制备及其染料废水中的应用 总被引:8,自引:0,他引:8
以城市污水厂活性污泥为原料,用3 mol/L ZnCl2溶液活化,通入水蒸气作活化气制备活性炭吸附剂.实验结果表明,温度为600℃条件下,活化时间为1 h,制得的活性炭其碘吸附值为374.10 mg/g,比表面积为381.62 m2/g,孔容积为0.25 cm3/g,微孔容积为0.11cm3/g.并进一步将生物质活性炭应用于染料废水的处理,考察了吸附时间、活性炭投加量和pH对色度及TOC的脱除效果的影响.室温下,酸性大红GR染料废水初始浓度为300 mg/L,污泥活性炭的最佳投加量为2%(质量分数),吸附15min,废水色度脱除率可达99.6%,TOC去除率可达99.7%,利用等温吸附实验作吸附等温线,吸附等温线可以用Freundlich或Langmuir方程描述. 相似文献
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微波法制备污泥活性炭研究 总被引:4,自引:0,他引:4
采用微波加热法,以污水厂剩余污泥为原料,磷酸为污泥活化剂制备污泥活性炭.微波功率、辐照时间和磷酸浓度对污泥活性炭吸附性能具有显著影响,在最佳工艺条件微波功率480 W、辐照时间315 s和磷酸浓度40%条件下制得的活性炭碘值301 mg/g,比表面积168 m2/g,污泥中重金属绝大部分被固化.与传统商品炭相比,污泥炭孔隙结构以中孔为主.利用该活性炭处理城市生活污水处理厂出水,COD去除率可达87%以上,污泥炭的吸附等温线用Langmuir等温吸附模型进行描述. 相似文献
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污泥-秸秆基活性炭的制备及其对渗滤液COD的吸附 总被引:5,自引:0,他引:5
以市政污泥与玉米秸秆为原料,采用化学活化法热解制备污泥-秸秆基活性炭,研究其物化性质、热解动力学特性及对渗滤液中COD的吸附性能。考察吸附剂投加量、吸附时间和溶液pH对COD去除率的影响,并用吸附等温线对吸附数据进行了拟合。结果表明,秸秆比例越高,活性炭的吸附碘值和BET比表面积越大,最大可达663 mg/g和902 m2/g;活性炭表面呈不规则的多孔状;秸秆比例为45%的活性炭在最佳实验条件下对COD的吸附去除率为82%;活性炭对COD的吸附符合Langmuir和Freundlich等温模型。 相似文献
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生活垃圾堆肥浸提液组成及其演化规律 总被引:2,自引:0,他引:2
堆肥浸提液与渗滤液组成相似,研究生活垃圾堆肥浸提液组成与演化特征可以为堆肥过程污染控制和堆肥质量改善提供科学依据。通过基本理化指标和三维荧光光谱分析,研究了生活垃圾堆肥浸提液的组成和转化特性。结果显示,在堆肥一次和二次发酵过程中,浸提液pH由5.43上升至9.24,无机阴离子无显著变化,电导率(EC)稳定在7.50 mS/cm上下波动,ORP为正值,总氮从611.08 mg/L下降至177.43 mg/L,NH4+-N和NO3--N浓度变化不明显,NO2--N从未检出到后期达10.28 mg/L,有机氮从246.64 mg/L下降至172.52 mg/L。溶解性有有机物含量(DOC)从7 419.00 mg/L降至5 569.00 mg/L,其中的有机物发生降解和转化,生成胡敏酸和富里酸等物质。浸提液中重金属Fe、Cd、Cu、Zn、Cr、Mn、Ni和 As浓度升高。通过研究发现,在堆肥中添加木屑等填料可以降低浸提液中NH4+-N的浓度,具有除臭作用,同时对pH值、EC和ORP均有调节作用,能提高堆肥的土地可利用性。 相似文献
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Effect of inoculation methods on the composting efficiency of municipal solid wastes 总被引:3,自引:0,他引:3
Four types of inoculation methods were studied during the composting of municipal solid wastes and dry grass (MSWG). The methods included a control group as well as initial-stage, two-stage, and multi-stage inoculations. Fulvic acids were extracted from the composting materials and characterized by spectroscopic techniques. The results showed that inoculation of microbes in MSWG enhanced the biodegradation of aliphatics, proteins, and polysaccharides. The inoculation also increased the molecular weight, humic- and fulvic-like compound content, as well as humification degree of the composting products. The inoculation of microbes in MSWG significantly improved composting process and efficiency. The improvement efficiency was in the order of initial-stage < two-stage < multi-stage inoculations. Inoculation of microbes based on composting organic matter composition and temperature enhanced composting efficiency. 相似文献
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城市生活垃圾填埋初期有机质演化规律研究 总被引:3,自引:1,他引:3
为阐明生活垃圾填埋初期有机质演化规律,于填埋场打井采集填埋1~3年3个不同时期垃圾样品,用水浸提制备水溶性有机物(DOM)。采用红外光谱、同步荧光光谱及紫外光谱,对浸提液中DOM的结构和演化特征进行了研究。结果显示,生活垃圾中含有脂肪类、蛋白类、糖类及木质素类物质,在填埋初期,有机质中的脂肪类、蛋白质类、糖类及木质素类物质均发生了降解,羧基、氨类及水溶性芳香结构物质减少,DOM分子量降低。研究结果表明,垃圾填埋初期有机质以降解为主。 相似文献
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Dipanjali Majumdar Anjali Srivastava 《Journal of the Air & Waste Management Association (1995)》2013,63(4):398-407
Improper solid waste management leads to aesthetic and environmental problems. Emission of volatile organic compounds (VOCs) is one of the problems from uncontrolled dumpsite. VOCs are well known to be hazardous to human health and many of them are known or potential carcinogens. They also contribute to ozone formation at ground level and climate change as well. The qualitative and quantitative analysis of VOCs emitting from two municipal waste (MSW) disposal sites in Mumbai, India, namely Deonar and Malad, are presented in this paper. Air at dumpsites was sampled and analyzed on gas chromatography–mass spectrometry (GC-MS) in accordance with U.S. Environmental Protection Agency (EPA) TO-17 compendium method for analysis of toxic compounds. As many as 64 VOCs were qualitatively identified, among which 13 are listed under Hazardous Air Pollutants (HAPs). Study of environmental distribution of a few major VOCs indicates that although air is the principal compartment of residence, they also get considerably partitioned in soil and vegetation. The CO2 equivalent of target VOCs from the landfills in Malad and Deonar shows that the total yearly emissions are 7.89E+03 and 8.08E+02 kg, respectively. The total per hour ozone production from major VOCs was found to be 5.34E-01 ppb in Deonar and 9.55E-02 ppb in Malad. The total carcinogenic risk for the workers in the dumpsite considering all target HAPs are calculated to be 275 persons in 1 million in Deonar and 139 persons in 1 million in Malad.
Implications: This paper describes the hazards of VOC emission from open dumpsites, a common practice, in an Indian metro city. The subsequent partitioning of the emitted VOCs in other environmental compartment from air is presented. The global warming potential and the health hazards to the dumpsite workers from the emitted VOCs have also been estimated. 相似文献
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Volatile organic compound emissions from municipal solid waste disposal sites: a case study of Mumbai, India 总被引:1,自引:0,他引:1
Majumdar D Srivastava A 《Journal of the Air & Waste Management Association (1995)》2012,62(4):398-407
Improper solid waste management leads to aesthetic and environmental problems. Emission ofvolatile organic compounds (VOCs) is one of the problems from uncontrolled dumpsite. VOCs are well known to be hazardous to human health and many of them are known or potential carcinogens. They also contribute to ozone formation at ground level and climate change as well. The qualitative and quantitative analysis of VOCs emitting from two municipal waste (MSW) disposal sites in Mumbai, India, namely Deonar and Malad, are presented in this paper. Air at dumpsites was sampled and analyzed on gas chromatography-mass spectrometry (GC-MS) in accordance with U.S. Environmental Protection Agency (EPA) TO-17 compendium method for analysis of toxic compounds. As many as 64 VOCs were qualitatively identified, among which 13 are listed under hazardous air pollutants (HAPs). Study of environmental distribution of a few major VOCs indicates that although air is the principal compartment of residence, they also get considerably partitioned in soil and vegetation. The CO2 equivalent of target VOCs from the landfills in Malad and Deonar shows that the total yearly emissions are 7.89E+03 and 8.08E+02 kg, respectively. The total per hour ozone production from major VOCs was found to be 5.34E-01 ppb in Deonar and 9.55E-02 ppb in Malad. The total carcinogenic risk for the workers in the dumpsite considering all target HAPs are calculated to be 275 persons in 1 million in Deonar and 139 persons in 1 million in Malad. 相似文献
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有机固体废物堆肥化处理的微生物学机理研究 总被引:9,自引:0,他引:9
由于符合持续发展的理念 ,利用微生物技术处理有机固体废物越来越受到人们的重视 ,其核心问题则是木质纤维素的生物降解。随着园林废物等高木质纤维素含量的城市生活垃圾的不断增加 ,以及对农业固体废物和食品工业废物再利用的需要 ,这一领域的研究取得了很大的进展。在研究中 ,针对好氧堆肥和厌氧发酵 2项主要的微生物处理技术 ,对其优势微生物菌群、不同降解底物和微生物降解动力学方面的最新研究进展进行了回顾和总结 ,并对环境微生物制剂的应用以及有机固体废物的微生物处理技术的发展做了合理的展望。 相似文献