共查询到20条相似文献,搜索用时 218 毫秒
1.
2.
3.
不同物质对垃圾渗滤液中腐殖酸的吸附研究 总被引:1,自引:0,他引:1
垃圾渗滤液是一种有毒有害的高浓度有机废水,其中含大量腐殖酸。腐殖酸具有离子交换能力、吸附能力和脱除杂质能力,因此在很多方面有实用价值。活性碳、土壤、堆肥对废水中的有机物有一定的吸附能力。本文采用正交设计的方法,研究了活性碳、土壤、堆肥在不同温度,液/固,腐殖酸初始浓度的条件下对垃圾渗滤液中腐殖酸的吸附效果。实验结果表明:四种实验因素对吸附剂的吸附能力的影响程度为:吸附剂类型〉腐殖酸的初始浓度〉吸附反应温度〉液固比。在温度为25℃,液固比为50/0.5(mL/g),腐殖酸初始浓度为41.99(mg/L),吸附剂类型为活性碳时,腐殖酸吸附量最大,为40.86mg。同时分析了响应指标随因素的变化趋势。 相似文献
4.
化学活化法制备麻疯树果壳活性炭的实验研究 总被引:1,自引:0,他引:1
以麻疯树果壳为原料,KOH为活化剂,通过化学活化法制备活性炭。考察了反应温度、反应时间和碱炭比(KOH与麻疯树果壳炭化料的质量比)等因素对活化结果的影响,并利用N2吸附和BET等现代分析测试方法来表征活性炭的结构特征。结果表明,化学活化法制备的活性炭吸附剂性能较好,且当活化温度为850℃,活化时间为240min,碱炭比R=4时制得活性炭产品的质量最好;化学活化法制备的活性炭为微孔吸附剂,在最佳条件下得到最大的碘吸附值和比表面积分别为2218.44mg/g和1890m^2/g。 相似文献
5.
6.
采用镍和铜作为溶液中的吸附质,探讨了蒙脱石对这2种重金属的吸附性能。通过实验研究了p H值、吸附剂用量、反应时间、浓度等因素对吸附Ni2+和Cu2+的影响。根据实验结果可知,蒙脱石对金属离子的吸附效率随溶液p H值、吸附剂用量、反应时间的增加而增加,但随着金属离子浓度的增加而降低。吸附动力学研究表明,蒙脱石对Ni2+和Cu2+的吸附过程符合准2级动力学模型。 相似文献
7.
本文主要研究新疆特色罗布麻茶的茶叶渣对水中锰、铁、锌三种金属离子的吸附能力。通过优化吸附效率的影响因素,制备的废茶渣吸附剂,在不同的加入量、吸附时间、反应温度及模拟废水初始金属离子浓度等条件下,分析其对水中金属离子的吸附率和吸附量,建立废茶渣作为吸附剂对工业废水中金属离子进行去除的方法。结果表明,吸附剂的使用量在30 g/500 mL、吸附温度20℃、吸附时间60 min,罗布麻茶渣对实际废水中锰、铁、锌三种金属离子的吸附效率在71.6%~81.6%。通过本次研究可以发现在试验条件下对废水中三种金属离子有较好的吸附作用,作为废弃茶叶渣回收与制备的生物吸附剂产品,具有较好的应用前景。 相似文献
8.
用红外分光光度法测定水中石油类,对测定原理、测定方法的检出限、硅酸镁吸附剂的特性、作用进行分析,讨论了硅酸镁活性和含水量的关系,以及降低活性后的硅酸镁对总萃取液中含极性分子动植物油的吸附性能。硅酸镁活性与含水量有关,可控制含水量使其对动植物油具有最佳吸附性能。 相似文献
9.
10.
挥发性有机废气净化技术研究进展 总被引:16,自引:4,他引:16
本文对生物净化技术、等离子体净化技术、吸附和催化氧化技术在控制废气中挥发性有机物的研究进展及应用进行了综述。气体生物净化技术在VOCs混合物和改进设备工艺方面开展的研究工作较多,等离子体净化技术与催化技术的组合越来越受到关注。吸附和催化氧化方面则着重在吸附剂(活性炭和沸石)吸附性能的进一步研究和新型催化剂的研制。 相似文献
11.
利用锆和氯化十六烷基三甲铵共同改性活性炭,制备一种新型去除污水中硝酸盐和磷酸盐的水处理吸附剂,并考察吸附剂加量、反应温度、pH值、共存阴离子等影响因素对吸附效果的影响。结果表明:锆-氯化十六烷基三甲铵改性活性炭(Zr-CTAC-AC)吸附剂适用于硝酸盐和磷酸盐浓度在100mg/L以下的污水,随着Zr-CTAC-AC加量的增加,硝酸盐、磷酸盐去除率逐渐增加,单位吸附量逐渐下降,Zr-CTAC-AC加量为8g/L时,硝酸盐去除率为79%,Zr-CTAC-AC加量为4.0g/L时,磷酸盐去除率可达91%,但应在较低的pH值范围内使用;反应温度对Zr-CTAC-AC的吸附效果影响不大;共存Cl-、HCO3-和SO42-可使硝酸盐的吸附率降低,但对磷酸盐吸附率影响较小;1mol/L NaCl溶液可使吸附到Zr-CTAC-AC表面的硝酸盐90.9%左右被解吸出来,1mol/L NaOH溶液可使吸附到Zr-CTAC-AC表面的磷酸盐78.4%左右被解吸出来。Zr-CTAC-AC能够有效去除污水中硝酸盐和磷酸盐,制备方法简单,且可循环利用,处理成本低。 相似文献
12.
Violeta Neagu Carmen Paduraru Ion Bunia Lavinia Tofan 《Journal of environmental management》2009,91(1):270-276
Two acrylic adsorbents with different morphological structures and bearing amidoethylenamine and thiol groups were obtained and used for platinum sorption from chloride solution by the batch method. Physico-chemical parameters that influence adsorption such as initial Pt(IV) concentration, stirring time, pH, and adsorbent amount were investigated. The thermodynamic parameters of Pt(IV) sorption on the synthesized adsorbent were also evaluated based on Langmuir and Freundlich isotherms. Thermodynamic parameters estimated from Langmuir constants indicated that the adsorption is spontaneous, exothermic and there is a disordered state at the molecular level. The models used to analyze the sorption rate led to the conclusion that the most important step in the sorption of Pt(IV) could be both particle diffusion and chemical reaction of [PtCl6]− with amine functional groups. Thus, both the ion exchange and complex formation mechanisms can occur via nitrogen atoms in the recovery of Pt(IV) on the studied adsorbent. 相似文献
13.
以咪唑银配位聚合物{Ag(im)}n作吸附剂,对偶氮染料刚果红和甲基橙的吸附进行了研究,结果表明:刚果红的最佳吸附条件是吸附剂加入量为31.5mg,温度为30℃,pH值为3,吸附时间为70min,最高染料脱除率为90。7%;甲基橙的最佳吸附条件是吸附剂加入量为36.7mg,温度为30℃,pH值为2,吸附时间为50min,最高染料脱除率为58.3%。 相似文献
14.
Removal of chromium (VI) from aqueous solution using walnut hull 总被引:2,自引:0,他引:2
In this study, removal of chromium (VI) from aqueous solution by walnut hull (a local low-cost adsorbent) was studied. The extent of adsorption was investigated as a function of solution pH, contact time, adsorbent and adsorbate concentration, reaction temperature and supporting electrolyte (sodium chloride). The Cr (VI) removal was pH-dependent, reaching a maximum (97.3%) at pH 1.0. The kinetic experimental data were fitted to the first-order, modified Freundlich, intraparticle diffusion and Elovich models and the corresponding parameters were obtained. A 102.78 kJ/mol Ea (activation energy) for the reaction of chromium (VI) adsorption onto walnut indicated that the rate-limiting step in this case might be a chemically controlled process. Both the Langmuir and Freundlich isotherms were suitable for describing the biosorption of chromium (VI) onto walnut hull. The uptake of chromium (VI) per weight of adsorbent increased with increasing initial chromium (VI) concentration up to 240-480 mg/L, and decreased sharply with increasing adsorbent concentration ranging from 1.0 to 5.0 g/L. An increase in sodium chloride (as supporting electrolyte) concentration was found to induce a negative effect while an increase in temperature was found to give rise to a positive effect on the chromium (VI) adsorption process. Compared to the various other adsorbents reported in the literature, the walnut hull in this study shows very good promise for practical applicability. 相似文献
15.
《International Journal of Greenhouse Gas Control》2007,1(1):11-18
Vacuum swing adsorptive (VSA) capture of CO2 from flue gas and related process streams is a promising technology for greenhouse gas mitigation. Although early reports suggested that VSA was problematic and expensive, through the application of more logical process configurations that are appropriately coupled to the composition of the feed and product gas streams, we can now refute this early assertion. Improved cycle designs coupled with tighter temperature control are also helping to optimise performance for CO2 separation. Simultaneously, new adsorbent materials are being developed. These separate CO2 by selective (acid-base) reaction with surface bound amine groups (chemisorption), rather than on the basis of non-bonding interactions (physisorption). This report describes some of these recent developments from our own laboratories and points to synergies that are anticipated as a result of combining these improvements in adsorbent properties and VSA process cycles. 相似文献
16.
《International Journal of Greenhouse Gas Control》2007,1(3):355-359
Shaped zeolite 13X adsorbent with kaolin as binder was hydrothermally modified in sodium hydroxide solution to improve its adsorption performance. The characterization of the product by XRD, N2 adsorption–desorption and water vapour adsorption displayed that kaolin component in zeolite adsorbent can be converted into zeolite during the alkali treatment, resulting in the modified adsorbent consisting entirely of effectual adsorption composition. Compared with the unmodified adsorbent, the modified adsorbent exhibited higher adsorption capacity and uptake rate for carbon dioxide, because of the increase of effective adsorption surface and the decrease of diffusion resistance owing to conversion of kaolin binder into zeolite. The model parameters of isotherms and the isosteric heats calculated by the Clausius–Clapeyron equation for CO2 adsorption showed the stronger interaction of adsorbate–adsorbent and the higher degree of heterogeneity of adsorption centers in modified than unmodified adsorbents. 相似文献
17.
利用HDTMA改性沸石制成吸附剂,研究对水体中硝酸盐的吸附能力和机理及吸附剂残渣的资源化应用前景。结果表明:HDTMA改性沸石可增强其对硝酸盐的吸附能力。通过红外光谱和差热分析它的吸附机理,表明:改性沸石HZ4吸附有十六烷基三甲基溴化铵(HDTMA)分子;吸附剂残渣NHZ4吸附有十六烷基三甲基溴化铵(HDTMA)分子和硝酸盐。盆栽实验结果表明:吸附剂残渣NHZ4能提高玉米生物量,最大增幅为30.4%。 相似文献
18.
Removal of arsenic from wastewater using iron compound: Comparing two different types of adsorbents in the context of LCA 总被引:1,自引:0,他引:1
Gjergj Dodbiba Teiji Nukaya Yousuke Kamioka Yuji Tanimura Toyohisa Fujita 《Resources, Conservation and Recycling》2009,53(12):688-697
A study was carried out in order to compare the environmental performance of two different types of adsorbents in removing arsenic (As) from wastewater. A FeCl3-based adsorbent and a poly-Fe-based adsorbent were first synthesized and their abilities in adsorbing As from wastewater were investigated in terms of the adsorption density and the rate of adsorption. Here, it should be noted that the main material being used in the synthesis of the poly-Fe-based adsorbent was a waste product, known as polyferric sulfate or poly-Fe in short, which exits the manufacturing process of titanium dioxide.Both adsorbents were then compared in the context of life-cycle assessment (LCA). In other words, the experimental results (i.e. the value of the adsorption density and the rate of adsorption) were input into the LCA model in order to assess the environmental performance of each adsorbent in removing arsenic. An estimate for the environmental burden of each option was finally calculated as the sum of the depletion of abiotic resources (ADP), the global warming potential (GWP), the acidification potential (AP), the photo-oxidant formation potential (POCP), the eutrophication potential (EP), and the human toxicity potential (HTP). The main finding of this study was that the adsorption of arsenic by using the poly-Fe-based adsorbent is more attractive treatment option in the environmental protection point of view than the adsorption by using the FeCl3-based adsorbent, which generates a relatively larger environmental burden. 相似文献
19.
《Resources, Conservation and Recycling》2010,54(12):688-697
A study was carried out in order to compare the environmental performance of two different types of adsorbents in removing arsenic (As) from wastewater. A FeCl3-based adsorbent and a poly-Fe-based adsorbent were first synthesized and their abilities in adsorbing As from wastewater were investigated in terms of the adsorption density and the rate of adsorption. Here, it should be noted that the main material being used in the synthesis of the poly-Fe-based adsorbent was a waste product, known as polyferric sulfate or poly-Fe in short, which exits the manufacturing process of titanium dioxide.Both adsorbents were then compared in the context of life-cycle assessment (LCA). In other words, the experimental results (i.e. the value of the adsorption density and the rate of adsorption) were input into the LCA model in order to assess the environmental performance of each adsorbent in removing arsenic. An estimate for the environmental burden of each option was finally calculated as the sum of the depletion of abiotic resources (ADP), the global warming potential (GWP), the acidification potential (AP), the photo-oxidant formation potential (POCP), the eutrophication potential (EP), and the human toxicity potential (HTP). The main finding of this study was that the adsorption of arsenic by using the poly-Fe-based adsorbent is more attractive treatment option in the environmental protection point of view than the adsorption by using the FeCl3-based adsorbent, which generates a relatively larger environmental burden. 相似文献
20.
F. Boudrahem F. Aissani-Benissad H. Aït-Amar 《Journal of environmental management》2009,90(10):3031-3039
Lignocellulosic materials are good precursors for the production of activated carbon. In this work, coffee residue has been used as raw material in the preparation of powder activated carbon by the method of chemical activation with zinc chloride for the sorption of Pb(II) from dilute aqueous solutions.The influence of impregnation ratio (ZnCl2/coffee residue) on the physical and chemical properties of the prepared carbons was studied in order to optimize this parameter. The optimum experimental condition for preparing predominantly microporous activated carbons with high pore surface area (890 m2/g) and micropore volume (0.772 cm3/g) is an impregnation ratio of 100%. The developed activated carbon shows substantial capability to sorb lead(II) ions from aqueous solutions and for relative impregnation ratios of 75 and 100%, the maximum uptake is practically the same. Thus, 75% represents the optimal impregnation ratio.Batch experiments were conducted to study the effects of the main parameters such as contact time, initial concentration of Pb(II), solution pH, ionic strength and temperature. The maximum uptake of lead(II) at 25 °C was about 63 mg/g of adsorbent at pH 5.8, initial Pb(II) concentration of 10 mg/L, agitation speed of 200 rpm and ionic strength of 0.005 M. The kinetic data were fitted to the models of pseudo-first order and pseudo-second order, and follow closely the pseudo-second order model. Equilibrium sorption isotherms of Pb(II) were analyzed by the Langmuir, Freundlich and Temkin isotherm models. The Freundlich model gives a better fit than the others.Results from this study suggest that activated carbon produced from coffee residue is an effective adsorbent for the removal of lead from aqueous solutions and that ZnCl2 is a suitable activating agent for the preparation of high-porosity carbons. 相似文献