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1.
Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH scope of 1-5.5 for Au(Ⅲ) and 2.0-4.5 for Cu(Ⅱ), room temperature, biomass concentration of 10.0g.L^-1 and sorotion du-ration more than 10 min. When the initial metal concentration were within 500mg.L^-1, the maximum biosorption capacity of 1.0g of MTB (dry mass basis) for Au(Ⅲ) and Cu(Ⅱ) were calculated as 505.2mg of Au(Ⅲ) and 493.1mg of.Cu(Ⅱ) by Langmuir model in single system, respectively. The isotherm equilibrium of Au(Ⅲ) and Cu(Ⅱ) ions in the Au-Cu binary system reflected a unique phenomenon that the adsorption of Au(Ⅲ) was rein-forced and that of Cu(Ⅱ) prohibited, compared respectively-with their performances in the single metal system.When the,concentration of-Au(Ⅲ) and Cu(Ⅱ). were below 80mg.L^-1, the waste waterafter MTB treating, wasbelow 1.0mg.L^-1, which is in conformity with Environmental Performance Standards (EPS) of Canada. Besides, all the kinetic data were fitted well to the pseudo second-order kinetic model with a high correlation coefficient (R^2〉0.999).  相似文献   

2.
《分离科学与技术》2012,47(3):591-609
Abstract

The aniline moiety was covalently grafted onto silica gel surface. The modified silica gel with aniline groups (SiAn) was used for removal of Cu(II), Fe(III), and Cr(III) ions from aqueous solution and industrial effluents using a batch adsorption procedure. The maximum adsorption of the transition metal ions took place at pH 4.5. The adsorption kinetics for all the adsorbates fitted better the pseudo second‐order kinetic model, obtaining the following adsorption rate constants (k2): 1.233 · 10?2, 1.902 · 10?2, and 8.320 · 10?3 g · mg?1 min?1 for Cr(III), Cu(II), and Fe(III), respectively. The adsorption of these transition metal ions were fitted to Langmuir, Freundlich, Sips, and Redlich‐Peterson isotherm models; however, the best isotherm model fitting which presented a lower difference of the q (amount adsorbed per gram of adsorbent) calculated by the model from the experimentally measured, was achieved by using the Sips model for all adsorbates chosen. The SiAn adsorbent was also employed for the removal of the transition metal ions Cr(III) (95%), Cu(II) (95%), and Fe(III) (94%) from industrial effluents, using the batch adsorption procedure.  相似文献   

3.
《分离科学与技术》2012,47(16):4000-4022
Abstract

The biosorption of Cu(II) and Zn(II) using dried untreated and pretreated Citrus reticulata waste biomass were evaluated. The Cu(II) and Zn(II) sorption were found to be dependent on the solution pH, the biosorbent dose, the biosorbent particle size, the shaking speed, the temperature, the initial metal ions (800 mg/L), and the contact time. Twenty-eight physical and chemical pretreatments of Citrus reticulata waste biomass were evaluated for the sorption of Cu(II) and Zn(II) from aqueous solutions. The results indicated that biomass pretreated with sulphuric acid and EDTA had maximum Cu(II) and Zn(II) uptake capacity of 87.14 mg/g and 86.4 mg/g respectively. Moreover, the Langmuir isotherm model fitted well than the Freundlich model with R 2 > 0.95 for both metal ions. The sorption of Cu(II) and Zn(II) occurred rapidly in the first 120 min and the equilibrium was reached in 240 min. FTIR and SEM studies were also carried out to investigate functional groups present in the biomass and the surface morphological changes of biomass.  相似文献   

4.
The present study describes the successful fabrication of bio-polymeric nanocomposite bead (NCB) of alginate caged magnetic graphene oxide (Alg-MGO). NCB was obtained by crosslinking of sodium alginate and calcium ions in the presence of MGO. Analytical techniques Fourier transform infra-red (FT-IR), field emission scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX) were used to characterize the Alg-MGO. Analytical application is conducted with magnetic solid phase extraction (MSPE) method for determination of Cu(II) and Pb(II) in urine, saliva and river water sample. The linear concentration range obtained were 0.33–25.00 µg L??1 with appropriate coefficient of determination (R2?=?0.99) and low limit of detection (LOD?=?0.21–0.71 µg L??1, n?=?3). The newly developed MSPE-NCB was successfully validated with standard reference material (SRM 2670a, NIST). Metal ions removal process was studied at high concentration level (1–200 mg L??1) and isotherm models were applied. Langmuir isotherm is well fitted to experiments due to high value of coefficient of determination (R2) and proper adsorption capacity 96.13 and 103.09 mg g??1 obtained for Cu(II) and Pb(II), respectively. Thermodynamic model is suggested spontaneous process, endothermic nature and physical sorption mechanism for uptake of selected metal ions from aqueous solution.  相似文献   

5.
趋磁细菌对金属离子的吸附特性研究   总被引:1,自引:0,他引:1  
研究了单元体系和三元体系中趋磁细菌(MTB)对Au3 ,Cu2 和Ni2 的吸附特性,用Langmuir吸附等温模型拟合了吸附等温线实验数据。较高的相关系数表明该吸附过程可以用Langmuir模型来描述。在三元体系竞争吸附实验中,MTB对Au3 的吸附量较之单元系统有所增加,而Cu2 和Ni2 的吸附量明显降低。吸附动力学实验结果表明,MTB对三种金属离子的吸附都属于快速过程,对Au3 的吸附在短时间内可完成,而且几乎完全吸附。所有吸附过程均符合拟二阶动力学模型。  相似文献   

6.
Although the biosorption of single metal ions to various microorganisms has been extensively studied and adsorption isotherms have been developed for single metal ion situations, very little attention has been given to the bioremoval and the expression of the adsorption isotherms of multi-metal ions systems. In this study, the competitive biosorption of iron(III) and chromium(VI) to Chlorella vulgaris from a binary metal mixture was studied and compared with the single metal ion situation in a batch stirred system. The effects of pH and single and dual metal ion concentrations on the biosorption rates and equilibrium uptakes were investigated. The optimum biosorption pH for both metal ions was determined as 2·0. Multi-metal ion biosorption studies were also performed at this pH value. It was observed that the biosorption rates and yields and equilibrium uptakes of iron(III) or chromium(VI) ions were reduced by the presence of increasing concentrations of the other metal ion. Adsorption isotherms developed for both single and dual metal ion systems at the optimum pH were expressed by the non-competitive and competitive Langmuir and Freundlich adsorption models, and model parameters were determined by computer. It was seen that the adsorption equilibrium data fitted very well to both of the models in the concentration ranges studied. ©1997 SCI  相似文献   

7.
《分离科学与技术》2012,47(16):2383-2393
In this study, the adsorption of Cu(II) and Zn(II) ions from aqueous solutions onto amidoximated polymerized banana stem (APBS) has been investigated. Infrared spectroscopy was used to confirm graft copolymer formation and amidoxime functionalization. The different variables affecting the sorption capacity such as pH of the solution, adsorption time, initial metal ion concentration, and temperature have been investigated. The optimum pH for maximum adsorption was 10.5 (99.99%) for Zn2+ and 6.0 (99.0%) for Cu2+ at an initial concentration of 10 mg L?1. Equilibrium was achieved approximately within 3 h. The experimental kinetic data were analyzed using pseudo-first-order and pseudo-second-order kinetic models and are well fitted with pseudo- second-order kinetics. The thermodynamic activation parameters such as ΔGo, ΔHo, and ΔSo were determined to predict the nature of adsorption. The temperature dependence indicates an exothermic process. The experimental isotherm data were well fitted to the Langmuir model with maximum adsorption capacities of 42.32 and 85.89 mg g?1 for Cu(II) and Zn(II), respectively, at 20°C. The adsorption efficiency was tested using industrial effluents. Repeated adsorption/regeneration cycles show the feasibility of the APBS for the removal of Cu(II) and Zn(II) ions from water and industrial effluents.  相似文献   

8.
BACKGROUND: Bioaccumulation and biosorption by Pichia stipitis yeast has not yet been explored. This paper evaluates, for the first time, the use of both viable and nonviable P. stipitis yeast to eliminate Cu(II) and Cr(III) from aqueous solutions. The effect of Cu(II) and Cr(III) ions on the growth and bioaccumulation properties of adapted and nonadapted biomass is investigated as a function of initial metal concentration. Binding capacity experiments using nonviable biomass are also performed as a function of temperature. RESULTS: The addition of Cu(II) and Cr(III) had a significant negative effect on the growth of yeast. Nonadapted cells could tolerate Cu(II) and Cr(III) ions up to a concentration of 75 ppm. The growth rate of nonadapted and adapted cells decreased with the increase in Cu(II) and Cr(III) concentration. Adapted P. stipitis biomass was capable of removing Cu(II) and Cr(III) with a maximum specific uptake capacity of 15.85 and 9.10 mg g−1, respectively, at 100 ppm initial Cu(II) and Cr(III) concentration at pH 4.5. Adsorption data on nonviable cells were found to be well modeled by the Langmuir and Temkin isotherms. The maximum loading capacity of dry biomass predicted from Langmuir isotherm for Cu(II) and Cr(III) at 20 °C were 16.89 and 19.2 mg g−1, respectively, at pH 4.5. Biosorptive capacities were dependent on temperature for Cu(II) and Cr(III) solutions. CONCLUSION: Cu(II)‐ and Cr(III)‐adapted cells grow and accumulate these ions at high ratios. On the other hand, nonviable P. stipitis was found to be an effective biosorbent for Cu(II) and Cr(III) biosorption. Copyright © 2008 Society of Chemical Industry  相似文献   

9.
《分离科学与技术》2012,47(8):1167-1176
The present research is to investigate the possibility of macrofungus Lycoperdon perlatum biomass, which is an easily available, renewable plant, low-cost, as a new biomass for the removal of mercury (Hg(II)) ions from aqueous solutions. The effects of various parameters like pH of solution, biomass concentration, contact time, and temperature were studied by the using the batch method. The Langmuir model adequately described the equilibrium data. The biosorption capacity of the biomass was found to be 107.4 mg · g?1 at pH 6. The mean free energy value (10.9 kJ · mol?1) obtained from the D–R model indicated that the biosorption of Hg(II) onto fungal biomass was taken place via chemical ion-exchange. Thermodynamic parameters showed that the biosorption of Hg(II) onto L. perlatum biomass was feasible, spontaneous, and exothermic in nature. The kinetic results showed that the biosorption of Hg(II) onto fungal biomass followed second-order kinetics. This work also shows that L. perlatum biomass can be an alternative to the expensive materials like ion exchange resins and activated carbon for the treatment of water and wastewater containing mercury ions due to its ability of selectivity and higher biosorption capacity and also being low cost material.  相似文献   

10.
《分离科学与技术》2012,47(6):997-1004
Equilibrium, thermodynamic, and kinetic studies on the biosorption of Cu(II) using biomass, Trichoderma viride were carried out. The biosorbent was characterized by Fourier transform infrared spectroscopy and Scanning Electron Microscopy. The Langmuir and Freundlich isotherm models were applied to describe the biosorption process. The influence of pH, the biomass dosage, the contact time, the initial metal ion concentration, and the temperature of the solution on the biosorption was studied. The maximum Cu(II) biosorption was attained at pH 5. The equilibrium data were better fit by the Langmuir isotherm model than by the Freundlich isotherm. The maximum biosorption capacity of T. viride biomass was found to be 19.6 mg/g for Cu(II). The kinetic studies indicated that the biosorption of Cu(II) followed the pseudo-second-order model. The calculated thermodynamic parameters, Gibbs-free energy (ΔGo), enthalpy (ΔHo), and entropy (ΔSo) showed that the biosorption of Cu(II) onto T. viride biomass was spontaneous and endothermic. It can be concluded that the T. viride biomass has the potential as an effective and low-cost biosorbent for Cu(II) removal from aqueous solutions.  相似文献   

11.
《分离科学与技术》2012,47(18):2843-2851
A novel adsorbent, chufa corm peels (CCP), is used for removing Cu(II), Cr(III), and Cr(VI) from aqueous solutions. The adsorption ability and characteristics of the CCP are thoroughly investigated. The adsorption capability for three heavy metal ions is in the order of Cu(II) > Cr(III) > Cr(VI). The morphology and elemental distribution on the biomass of CCP were evaluated by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Fourier-transform infrared spectroscopy (FTIR) analysis revealed that oxygen-containing functional groups, especially carboxylic and hydroxyl groups were responsible for chemical coordination between ionizable functional groups and metal ions. The adsorption features were evaluated based on the batch biosorption experiment. The results showed that the adsorption well meets the Freundlich adsorption isotherm models and pseudo-second-order kinetics model. In summary, this work demonstrated that CCP is an attractive, efficient, and low-cost adsorbent biomaterial that can be used for the removal of heavy metals from environmental contaminations.  相似文献   

12.
A linear sweep anodic stripping voltammetric method using a carbon nanotube–gold nanoparticle-modified vibrating screen printed electrode for the determination of arsenic(III) is reported. The experiments were conducted with a 0.1 mol L?1 solution of H2SO4 in order to estimate the electrode area related to gold oxide formation. The results showed a clear reduction peak at approximately +0.85 V corresponding to the reduction of the gold surface oxide with a superficial area of 0.089 cm2. A vibrating motor was attached to the screen printed electrode to create a portable and autonomous system with enhanced mass transfer. The repeatability of the measurements was 2.4 % (n = 10) at the level of 0.5 mg L?1 of arsenic(III) under the best instrumental operating conditions. The peak current was linearly dependent on the arsenic(III) concentration, thus allowing the construction of a linear analytical curve in the range from 10 to 550 μg L?1 with the equation: ?Ip (μA) = 0.05 + 134.59 [As(III) (μg L?1)], R2 = 0.99. The obtained detection and quantification limits were 0.5 (3 SD) and 1.5 (10 SD) μg L?1, respectively, using 120 s as the deposition time. It was shown that Cu(II) does not interfere in the detection of As(III) using the proposed method.  相似文献   

13.
Thiourea–formaldehyde (TF) and urea–formaldehyde (UF) chelating resins were synthesized and these resins were used in the separation of gold(III) ions from copper(II) and zinc(II) base metal ions. In the experimental studies, the effect of acidity on gold(III) uptake and gold(III) adsorption capacities by batch method, and loading and elution profiles of gold(III) ions, gold(III), copper(II), and zinc(II), dynamic adsorption capacities and the stability tests of TF and UF resins by column method were examined. By batch method, the optimum acidities were found as pH 2 and 0.5M HCl, and gold(III) adsorption capacities in the solutions including copper(II) and zinc(II) ions were obtained as 0.088 and 0.151 meq Au(III)/g for UF and TF resins, respectively. On the other hand, by column method, the dynamic adsorption capacities were calculated as 0.109 meq Au(III)/g with TF, 0.023 meq Au(III)/g with UF, 0.015 meq Cu(II)/g with TF, 0.0057 meq Cu(II)/g with UF, and under 6.1 × 10?5 meq Zn(II)/g with TF or UF. TF resin was more effective in the separation and the concentration of gold(III) ions from copper(II) and zinc(II) ions than UF resin. It was seen that sulfur atoms contributed the gold(III) adsorption comparing with oxygen atoms. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

14.
《分离科学与技术》2012,47(16):3641-3656
Abstract

An attempt was made to assess the biosorption potential of rose waste biomass for the removal of Pb(II) and Co(II) ions from synthetic effluents. Biosorption of heavy metal ions (>90%) reached equilibrium in 30 min. Maximum removal of Pb(II) and Co(II) occurred at pH 5 and 6 respectively. The biosorbent dose for efficient uptake of Pb(II) and Co(II) was 0.5 g/L for both metals. The biosorbent size affected the Pb(II) and Co(II) biosorption rate and capacity. Rose waste biomass was found effective for Pb(II) and Co(II) removal from synthetic effluents in the concentration range 10–640 mg/L. Equilibrium sorption studies showed that the extent of Pb(II) and Co(II) uptake by the rose waste biomass was better described by the Langmuir isotherm in comparison to the Freundlich model. The uptake capacities of the two metal ions were 156 and 27.15 mg/g for Pb(II) and Co(II) respectively.  相似文献   

15.
16.
The biosorption and detoxification performance of Lysinibacillus fusiformis KMNTT-10 biomass for lead(II) was investigated. The optimum conditions for Pb(II) adsorption were found to be pH 6.0 and contact time 90 min at 27 ± 2°C. Equilibrium data of Pb(II) adsorption fitted well with the Langmuir isotherm model and followed pseudo-second-order model. SEM-EDX analysis revealed a blister like protrusions formed on the biomass surface after Pb(II) biosorption. FTIR spectra indicated that anionic functional groups on the biomass surface took part in the adsorption process. Further, X-ray diffraction analysis showed that the adsorbed Pb(II) was transformed (detoxified) into less soluble PbS (galena).  相似文献   

17.
Fe (III)-loaded chitosan (CS) hollow fibers (CS-Fe (III) HF) were successfully prepared according to the dry-wet spinning technique. The CS-Fe (III) HFs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA). Removal of pentavalent arsenic was studied through biosorption on CS-Fe (III) HF adsorptive membranes. The response surface methodology (RSM) was applied to investigate the influence of the main operating parameters such as contact time, pH, initial As (V) concentration and HFs dosage on the adsorption capacity of As (V). From the Pareto analysis, pH, [As (V)]o, [CS-Fe (III) HF membranes] and squared effect of [As(V)]o were found to produce the largest effect on biosorption of As (V). Kinetic studies showed that the pseudo-second-order kinetic model provides the best correlation to the experimental results. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 3,703 μg g?1. A laboratory scale glass membrane module consisting of three CS-Fe(III) HFs has also been prepared and tested for biosorption of As (V) at a real scale. Permeability of As (V) ions through the CS-Fe (III) HF membranes was 0.145 μmol m?2 h?1 bar ?1.  相似文献   

18.
《分离科学与技术》2012,47(6):875-885
The adsorption of Zn(II) and Cu(II) ions onto two dry macrophytes used as biosorbents was investigated in batch systems. All single and binary metal sorption experiments using Egeria densa and Eicchornia crassipes biomasses as biosorbents were performed under constant shaking, at pH 5, with mixed grain size, and drying and sorption temperatures of 30°C. A 20–45 min equilibrium time range was attained with E. densa, whereas a 30–60 min equilibrium time was achieved with E. crassipes. It was also found that the overall adsorption kinetic data was best described by the pseudo second-order kinetic model, and that the intra-particle diffusion model was involved in the sorption process. An extended-to-multi-component Langmuir-type isotherm model and a parameter identification procedure based on the PSO method have been effectively used for the reproduction of the experimental data and the prediction of the maximum adsorption capacities of Zn(II) and Cu(II) ions in a binary metal ion solution. Finally, E. densa and E. crassipes biomasses exhibited opposite metal adsorption affinity order in the Zn(II)-Cu(II) binary system.  相似文献   

19.
The biosorption properties of dead sulfate reducing bacteria (SRB) for the removal of Cu(II) and Fe(III) from aqueous solutions was studied. The effects of the biosorbent concentration, the initial pH value and the temperature on the biosorption of Cu(II) and Fe(III) by the SRB were investigated. FTIR analysis verified that the hydroxyl, carbonyl and amine functional groups of the SRB biosorbent were involved in the biosorption process. For both Cu(II) and Fe(III), an increase in the SRB biosorbent concentration resulted in an increase in the removal percentage but a decrease in the amount of specific metal biosorption. The maximum specific metal biosorption was 93.25 mg?g–1 at pH 4.5 for Cu(II) and 88.29 mg?g–1 at pH 3.5 for Fe(III). The temperature did not have a significant effect on biosorption. In a binary metal system, the specific biosorption capacity for the target metal decreased when another metal ion was added. For both the single metal and binary metal systems, the biosorption of Cu(II) and Fe(III) onto a SRB biosorbent was better represented by a Langmuir model than by a Freundlich model.  相似文献   

20.
Equimolar mixture of pyridine-2,6-dimethanol (PDM), and thiocyanate ion immobilized on silica serves as an efficient sorbent for selective retention of Cu(II) from other associated metal ions at µg g?1 level. The maximum sorption capacity for Cu(II) was found as 2.44 mmol g?1 at pH 6.0. The sorbed Cu(II) was completely eluted with 3 mol L?1 HNO3 and measured with a flame atomic absorption spectrometer (FAAS). The structure of the extracted Cu(II) complex was confirmed by single-crystal X-ray structure analysis and Fourier transform-infrared (FT-IR) spectroscopy. Thermogravimetric analysis (TGA) of the isolated Cu(II) complex was performed to determine its thermal stability at the extraction temperature. The three sigma detection limit (N = 15) of the method is 0.6 µ g mL?1 with a relative standard deviation (RSD) of 0.1% (N = 15). Pre-concentration factor of the method is 133. Slight interference from Mn2+ ion was eliminated by prior oxidation with potassium periodate. The developed method was tested for trace level separation and estimation of Cu(II) in certified reference materials and environmental samples.

[Supplementary materials are available for this article. Go to the publisher's online edition of Chemical Engineering Communications for the following free supplemental resources: two tables providing details of the bond lengths and bond angles of the Cu(II) complex.]  相似文献   

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