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In a multicomponent systems, the adsorption of Pb2+, Cu2+, and Ni2+ by date seed biochar exhibited competitive behavior. Compared to single component systems, the adsorption capacities of each ion were reduced by 48–75% in both batch and column experiments. Surface complexation with carboxyl and hydroxyl functional groups played a major role in the removal mechanism. Ion exchange mechanism accounted for 37–40% of the total adsorption compared to 57–72% in single component systems. Modified Langmuir isotherm best described the systems. Adsorption capacities and selectivity follow the order: Pb2+> Cu2+> Ni2+. Multi-stage sequences system is recommended to avoid premature exhaustion of biochar. 相似文献
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The adsorption properties of chitin adsorbent from mycelium of fermentation industries for the removal of heavy metal ions were studied.The result shows that the chitin adsorbent has high adsorption capacity for many heavy metal ions and Ni^2 in citric acid.The influence of pH was significant:When pH is higher than 4.0,the high adsorption capacity is obtained.otherwise H^ ion inhibits the adsorption of heavy metal ions.The comparison of the chitin adsorbent with some other commercial adsorbents was made,in which that the adsorption behavior of chitin adsorbent is close to that of commercial cation exchange adsorbents,and its cost is much lower than those commercial adsorbents. 相似文献
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改性泥炭对Pb2+、Ni2+、Cu2+的吸附性能研究 总被引:4,自引:0,他引:4
在静态条件下,研究了改性泥炭对重金属离子Pb2+、Ni2+、Cu2+的吸附性能,着重探讨了改性泥炭去除废水中重金属离子Pb2+、Ni2+、Cu2+的适宜条件,同时对改性泥炭的吸附及解吸再生机理进行了初步分析。结果表明:在25℃条件下,当pH值为5~7、吸附剂用量为2g/L、吸附时间为2h时,改性泥炭对Pb2+、Ni2+、Cu2+的去除率分别为98.0%、96.7%、95.5%。吸附了重金属离子的改性泥炭经酸解吸再生后,可循环使用,不会带来二次污染。 相似文献
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《分离科学与技术》2012,47(2):277-287
Competitive adsorption of Ag+, Pb2+, Ni2+, and Cd2 ions on vermiuculite in a binary, ternary, and quaternary mixture was investigated in batch experiments. The effects of the presence of Ag+, Ni2+, and Cd2+ ions on the adsorption of Pb2+ ions were investigated in terms of the equilibrium isotherm. Experimental results indicated that Pb2+ ions always favorably adsorbed on vermiculite over Ag+, Ni2+, and Cd2+ ions. The adsorption equilibrium data of Pb2+ ions better fitted the Langmuir model than the Freundlich model. The results showed that the pseudo-second-order kinetics model was in good agreement with the experimental results for all metal ions, and the adsorption rate among the metal ions followed Ag+ > Pb2+ > Ni2+ > Cd2+. The desorption and regenration study indicated that vermiculite can be used repeatedly and be suitable for the design of a continuous process. 相似文献
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Removal of Cd2+, Cu2+, Ni2+, and Pb2+ ions from aqueous solutions using tururi fibers as an adsorbent
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Diego Q. Melo Carla B. Vidal André Leandro da Silva Raimundo N. P. Teixeira Giselle Santiago Cabral Raulino Thiago C. Medeiros Pierre B. A. Fechine Selma Elaine Mazzeto Denis De Keukeleire Ronaldo F. Nascimento 《应用聚合物科学杂志》2014,131(20)
This work investigates the removal of Cd2+, Cu2+, Ni2+, and Pb2+ ions from aqueous solutions using tururi fibers as an adsorbent under both batchwise and fixed‐bed conditions. It was found that modification of the tururi fibers with sodium hydroxide increased the adsorption efficiencies of all metal ions studied. The fractional factorial design showed that pH, adsorbent mass, agitation rate, and initial metal concentration influenced each metal adsorption differently. The kinetics showed that multi‐element adsorption equilibria were reached after 15 min following pseudo‐second‐order kinetics. The Langmuir, Freundlich, and Redlich–Peterson models were used to evaluate the adsorption capacities by tururi fibers. The Langmuir model was found to be suitable for all metal ions. Breakthrough curves revealed that saturation of the bed was reached in 160.0 mL with Cd2+ and Cu2+, and 52.0 mL with Ni2+ and Pb2+. The Thomas model was applied to the experimental data of breakthrough curves and represented the data well. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40883. 相似文献
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将黏胶纤维在一定条件下进行羧甲基化改性,探讨了改性黏胶纤维对重金属离子Cu2+、Ni2+的吸附性能,以及黏胶的取代度、pH值、吸附温度及吸附时间对吸附性能的影响,同时研究了吸附动力学。结果表明,改性黏胶对两种离子都有良好的吸附性能,其中Ni2+的最佳吸附条件为:pH=5,温度50℃,饱和吸附量167 mg/g;Cu2+的最佳吸附条件为:pH=4~5,饱和吸附量108 mg/g;吸附重金属离子的改性黏胶纤维在pH<2时迅速解析,可循环利用。 相似文献
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《分离科学与技术》2012,47(15):2270-2276
The process of adsorption from water solutions containing ternary system of Cu(II), Zn(II) and Ni(II) ions in time-variable conditions in a packed column with lyophilized chitosan beads is considered. The system of partial differential equations describing the adsorption column, due to the assumption of a properly defined variable is transformed into a system of ordinary nonlinear equations which enables the identification of object parameters in simple experiments. Analytical solution of that system was possible due to the assumptions made regarding the equation describing sorption kinetics. Using experimental data, the effective diffusion coefficient Deff and the sorption kinetic constants K in the real environment were identified. The sorption capacity q* was obtained in separate sorption equilibrium experiments. Using a mathematical model the influence of initial concentration and solution flow rate on the breakthrough curve was determined. The approach which is presented provides a new method for modeling of sorption in a packed column. 相似文献
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泥炭中富含有机质与腐植酸,其中含有大量的极性基团,对金属离子有较强的吸附性能。本试验通过对泥炭吸附重金属废水中Cu^2+、Pb^2+种离子的吸附条件进行研究,得出最佳吸附条件为:当重金属离子浓度为30mg/L时,泥炭投加量分别为7g/L和5g/L,最佳吸附pH值分别为5和8,吸附时间均为30min.且离子浓度越高,表观吸附量越大,但除金属率越低。最佳条件下Cu^2+、Pb^2+的表观吸附量分别为4.24mg/g和6.00mg/g,除铜率和除铅率分别为98.8%和999%。 相似文献
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A novel chitosan-based adsorbent (CCTM) was prepared by the reaction of epichlorohydrin O-crosslinked chitosan with maleic anhydride under microwave irradiation. The chemical structure of this polymer was characterized by infrared spectroscopy and X-ray diffraction analyses. The effects of various variables such as degree of substitution, adsorption time, initial metal ion concentration, solution pH, and temperature, on the adsorption of Pb2+ and Cu2+ by CCTM were investigated. The results demonstrate that the microwave irradiation can remarkably enhance the reaction. CCTM has higher adsorption capacity than chitosan. The maximum adsorption capacities for Pb2+ and Cu2+, with initial concentrations of 0.02 mol L−1 at pH 5, are 246.3 and 132.5 mg g−1, respectively. The adsorbent can be recycled. These results have important implications for the design of effective chitosan-based adsorbents in the removal of heavy metal ions from wastewaters. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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通过凹土的表面功能化开发高性能低成本的吸附材料,采用溶液聚合法在其表面接枝聚丙烯酸,制备出聚丙烯酸/凹土吸附材料(PAA/ATP),系统考察了PAA/ATP对Pb2+、Ni2+和Cr3+三元混合体系的吸附性能。结果表明:PAA/ATP复合吸附材料的有机物接枝率为14.1%,其结构中出现聚丙烯酸的特征官能团;PAA/ATP吸附Pb2+的动力学符合拟二级动力学,即化学吸附是速率控制步骤,说明PAA/ATP对Pb2+的吸附是一个有化学作用的过程,吸附过程与Pb2+和吸附剂PAA/ATP表面官能团之间的电子转移或电子共用有关;PAA/ATP对Pb2+的吸附符合Langmuir吸附等温模型;PAA/ATP对Pb2+、Ni2+和Cr3+的竞争吸附能力依次为Pb2+ > Cr3+ > Ni2+,即对Pb2+具有较好的选择性吸附。 相似文献
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《分离科学与技术》2012,47(4):525-534
A novel immobilized metal affinity membrane was prepared for papain adsorption in this article. Higher papain adsorption capacity between 43-67 mg/g was observed and the adsorption isotherm fitted the Freundlich equation. Experimental data were analyzed using two adsorption kinetic models. The pseudo-second-order kinetic model provided better correlation to the experimental results. A significant amount of the adsorbed papain was eluted by 1.0 M NaSCN at pH 5.0 for all affinity membranes. It was concluded that the novel chitosan-coated nylon-based immobilized metal ion affinity membrane could be applied for the large-scale isolation of papain without resulting in enzyme denaturation. 相似文献
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壳聚糖超滤膜的制备及在低含量重金属废水处理中的应用 总被引:4,自引:0,他引:4
报道了壳聚糖超滤膜的制备及主要性能,确定了壳聚糖溶液成膜的最佳条件,制备的超滤膜透水速度为3~4mL cm2·h,对0.1%牛血清蛋白溶液的截留率可达90%。用此膜对低含量重金属废水进行处理,结果表明:通过调节溶液的pH值,使重金属离子在水溶液中形成胶体,用壳聚糖超滤膜可有效地去除水中Pb2+、Cd2+、Zn2+、Cu2+等金属离子的氢氧化物。 相似文献
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为了研究小球藻藻体吸附水体中Cd2+、Pb2+和Cu2+的情况,在检测了典型电子垃圾处理区水体中重金属Cd、Pb和Cu浓度的基础上,采用冷冻干燥的小球藻藻体在模拟重金属离子溶液中进行吸附试验。结果表明,水体中重金属Cu的浓度较高,Cd和Pb的污染程度较严重。藻体对于Pb2+的去除效果较好,去除率和去除量分别达到88.42%和13.262 4 mg/g;Cu2+的去除率较低,但去除量高达17.480 6 mg/g;Cd2+去除率较高,但去除量仅有0.433 7 mg/g。 相似文献