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1.
The removal of copper from aqueous solution by ion exchange resins, such as 1200H and IRN97H, is described. Effect of initial metal ion concentration, agitation time and pH on adsorption capacities of ion exchange resins was investigated in a batch mode. The adsorption process, which is pH dependent, shows maximum removal of copper in the pH range 2–7 for an initial copper concentration of 10 mg/L. The experimental data have been analyzed by using the Freundlich, Langmuir, Redlich-Peterson, Temkin and Dubinin-Radushkevich isotherm models. The batch sorption kinetics have been tested for a first-order, pseudo-first order and pseudo-second order kinetic reaction models. The rate constants of adsorption for all these kinetic models have been calculated. Results showed that the intraparticle diffusion and initial sorption into resins of Cu(II) in the ion exchange resins was the main rate limiting step. The uptake of copper by the ion exchange resins was reversible and thus has good potential for the removal/recovery of copper from aqueous solutions. We conclude that such ion exchange resins can be used for the efficient removal of copper from water and wastewater. This paper is dedicated to Professor Hyun-Ku Rhee on the occasion of his retirement from Seoul National University.  相似文献   

2.
In this article, the adsorption properties of poly(acrylaminophosphonic-carboxyl-hydrazide) chelating fibers for Cu(II), Cd(II), Co(II), Mn(II), Pb(II), Zn(II), Ni(II), and Cr(III) are investigated by a batch technique. Based on the research results of binding capacity, adsorption isotherm, effect of pH value on sorption, and adsorption kinetics experiments, it is shown that the poly(acrylaminophosphonic-carboxyl-hydrazide) chelating fibers have higher binding capacities and good adsorption kinetic properties for heavy metal ions. The sorption of the metal ions on the chelating fibers is strongly dependent on the equilibrium pH value of the solution. The adsorption isotherms of Cu(II) and Cd(II) on the chelating fiber exhibit a Langmuir-type equation. The adsorbed Cu(II), Cd(II), Zn(II), and Pb(II) could be eluted by diluted nitric acid. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 7–14, 1998  相似文献   

3.
The oil shale waste material, retorted shale, was utilized as an adsorbent for Cu(II) removal from aqueous solution. The kinetics and thermodynamic adsorption was investigated during a series of batch adsorption experiments. The removal efficiency was controlled by solution pH, temperature, initial ion concentration and contact time. Two simple kinetic models, pseudo-first-and second-order, were used to investigate the adsorption mechanisms. The pseudo-second-order chemical reaction kinetics provides the best correlation with the experimental data. Langmuir and Freundlich models were used to fit the equilibrium data, which showed that Langmuir best-fitted these data. Thermodynamic parameters such as free energy, enthalpy and entropy were calculated to predict the nature of the adsorption process.  相似文献   

4.
We first report a mechanism study on the adsorption of Cu(II)-Cr(VI) binary mixture by a novel low-cost adsorbent, carbonized Eupatorium adenophorum. The influences by pH value, dosage, initial concentration, temperature, and adsorption time on its performance to absorb copper and chromium were investigated. The experimental data were fitted according to the Langmuir and Freundlich adsorption isotherm models, the pseudo-first-order kinetics, the pseudo-second-order kinetics, and the intra-particle diffusion model. The results indicated that when the reaction system was with its pH = 5, the dosage of carbonized Eupatorium adenophorum was 0.1 g, the adsorption time was 30 min, and the temperature was 25°C; the adsorption capacities for Cu(II) and Cr(VI) reached 27.62 mg/g and 9.68 mg/g, respectively. The process of carbonized Eupatorium adenophorum to absorb Cr(VI) is also accompanied by redox reactions. The Langmuir model and the pseudo-second-order model can better ?t the experimental data. Observation by fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) found no significant change of functional groups before and after the adsorption by carbonized Eupatorium adenophorum, and this adsorption process is mainly a physical adsorption.  相似文献   

5.
The complexation agent 2[-bis-(pyridylmethyl) aminomethyl]-4-methyl-6-formyl-phenol (HL) was immobilized in chitosan in order to obtain a new adsorbent material to be employed in studies on adsorption and pre-concentration of Cu(II). The chitosan modified by the complexation agent was characterized by infrared spectroscopy, DSC and TGA. The studies were conducted as a function of the pH of the medium and the mechanism of Cu(II) adsorption in the solid phase was analyzed utilizing several kinetic models. The parameters for the adsorption of Cu(II) ions by chitosan-HL were determined with a Langmuir isotherm, the maximum saturation capacity of the monolayer being 109.4 mg of Cu(II) per gram of polymer. Electron paramagnetic resonance spectroscopy revealed that CuII ions coordinate to the donor atoms of the HL ligand anchored to the surface of the polymer forming a stable chelate complex in the solid state.  相似文献   

6.
Adsorption of Cd(II), Co(II), and Ni(II) on aminopyridine modified poly(styrene‐alt‐maleic anhydride) crosslinked by 1,2‐diaminoethane as an ion exchange resin has been investigated in aqueous solution. Adsorption behavior of these metal ions on the resin was studied by varying the parameters such as pH (2–6), adsorbent dose (0–4.0 g/L), contact time (0–240 min), and metal ions concentration (20–300 mg/L). Adsorption percentage was increased by increasing each of these parameters. The isotherm models such as: Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich were used to describe adsorption equilibrium. The results showed that the best fit was achieved with the Langmuir isotherm equation, yielding maximum adsorption capacities of 81.30, 49.02, and 76.92 mg/g for Cd(II), Co(II), and Ni(II), respectively. The pseudo‐first‐order, pseudo‐second‐order, and intra‐particle diffusion kinetics equations were used for modeling of adsorption data and it was shown that pseudo‐second‐order kinetic equation could best describe the adsorption kinetics. The intra‐particle diffusion study revealed that external diffusion might be involved in this case. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41642.  相似文献   

7.
The adsorption properties of poly(acrylamidoxime) chelating resin for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), Cr(III), and U(VI) are investigated by the batch technique. Based on the research results of the binding capacity effect of the pH value on sorption kinetic experiments, it is shown that this resin has higher binding capacity to uranyl ions, fast kinetics, and very good selectivity from binary metal ion mixtures with Cu(II) and Pb(II). The uranyl ion sorption strongly depends on the pH value of the solution. The highest value of 99% is at pH 5, but at pH 1 there is no retention. The adsorbed UO can be eluted by sulfuric acid and sodium carbonate. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1994–1999, 2000  相似文献   

8.
A novel nanometer-sized chelating resin (NSCR) was prepared via two steps, First step: copolymerization reaction of N-methacryloxyphtalimide (NMP) with methylenebisacrylamide (MBA) by suspension polymerization method to give ultrafine poly (NMP-co-MBA). Second step: reaction of triethylenetetramine (TETA) with poly (NMP-co-MBA) to give NSCR. The prepared NSCR was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Brunauer-Emmett-Taller (BET) and thermogravimetric analysis (TGA). This study illustrated the capability of NSCR for extraction of Cu(II), Co(II) and Ni(II) from aquatic solutions. The pH effect, metal ions concentration, temperature and contact time were elaborated in batch experiments. The results showed that high capacities were 1.3, 1.0 and 0.95 mmol/g resin for Cu(II), Ni(II) and Co(II) ions, respectively. The experimental data of adsorption isotherms were convenient for Langmuir isotherm, and the kinetic data illustrated that the removal process was described by pseudo-second order kinetic model. The parameters of Thermo dynamic illustrated that the process of adsorption was endothermic and spontaneous reaction. The prepared NSCR was regenerated and used repetitively for five times with small decrease in adsorption capacity.  相似文献   

9.
The adsorption properties of some novel chelating resins (CRs) bearing iminodiacetate groups for removal of heavy metal ions like: Cu(II), Co(II) and Ni(II) from aqueous solutions comparative with the commercial resin Amberlite IRC-748 have been studied in this work by a batch equilibrium technique. Quantitative analysis for adsorption was conducted using UV–vis spectroscopy to investigate the kinetics, adsorption isotherm and thermodynamics of the removal process considering equilibration time, pH, metal ion concentration and temperature as controlling parameters. The metal adsorption capacities, at pH 5, were in the order Cu(II) > Ni(II) > Co(II), for both the CR with 10 wt.% DVB (CR-10) and the commercial resin Amberlite IRC-748. The adsorption capacities on CR-10 were higher for Ni(II) and Co(II) ions, but lower for Cu(II) ions compared with Amberlite IRC-748. Both Freundlich and Langmuir isotherms well fitted on the adsorption results of Cu(II), Ni(II) and Co(II) ions on all iminodiacetate resins.  相似文献   

10.
螯合树脂对铜离子的吸附动力学和热力学   总被引:8,自引:0,他引:8  
针对以谷氨酰胺-铜(II)配合物为供体酶法制备茶氨酸体系,研究了D401螯合树脂对Cu2+的吸附,探讨了吸附过程的热力学和动力学,通过红外光谱鉴定了树脂的配位结构. 结果表明,树脂吸附量随离子浓度和温度升高而增加,当pH为5.6时吸附量最大,达1.887 mmol/g. 不同温度下Langmuir方程均呈现很好的拟合度. 热力学平衡方程计算得DG<0, DH=21.5 kJ/mol, DS>0,表明该吸附过程是自发的、吸热、熵增加的过程. 动力学研究表明,该过程符合准二级动力学模型,吸附反应速率由颗粒扩散和液膜扩散共同控制. 该树脂在较宽的pH范围内对Cu2+具有很好的选择吸附性,可用于酶转化茶氨酸体系中Cu2+的去除.  相似文献   

11.
Porous chitosan–tripolyphosphate beads, prepared by the ionotropic crosslinking and freeze‐drying, were used for the adsorption of Cu(II) ion from aqueous solution. Batch studies, investigating bead adsorption capacity and adsorption isotherm for the Cu(II) ion, indicated that the Cu(II) ion adsorption equilibrium correlated well with Langmuir isotherm model. The maximum capacity for the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, deduced from the use of the Langmuir isotherm equation, was 208.3 mg/g. The kinetics data were analyzed by pseudo‐first, pseudo‐second order kinetic, and intraparticle diffusion models. The experimental data fitted the pseudo‐second order kinetic model well, indicating that chemical sorption is the rate‐limiting step. The negative Gibbs free energy of adsorption indicated a spontaneous adsorption, while the positive enthalpy change indicated an endothermic adsorption process. This study explored the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, and used SEM/EDS, TGA, and XRD to examine the properties of adsorbent. The use of porous chitosan–tripolyphosphate beads to adsorb Cu(II) ion produced better and faster results than were obtained for nonporous chitosan–tripolyphosphate beads. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

12.
The adsorption behavior of poly(ethylene terephthalate) (PET) fibers towards copper(II), cobalt(II), and iron(III) ions in aqueous solutions was studied by a batch equilibriation technique. Influence of treatment time, temperature, pH of the solution, and metal ion concentration on the adsorption were investigated. Adsorption values for metal ion intake followed the following order: Co(II) > Cu(II) > Fe(III). One hour of adsorption time was found sufficient to reach adsorption equilibrium for all the ions. The rate of adsorption was found to decrease with the increase in the temperature. Langmuir adsorption isoterm curves were found to be significant for all the ions studied. The heat of adsorption values were calculated as −5, −2.8, and −3.6 kcal/mol for Cu(II), Co(II), and Fe(III) ions, respectively. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1935–1939, 1998  相似文献   

13.
Series of resin selection experiments were carried out and the KIP210 strong base anion exchange resin was confirmed to have the maximum equilibrium adsorption capacity to remove Cr(VI) from wastewater. The adsorption thermodynamics and kinetics of Cr(VI) on KIP210 resin were investigated completely and systematically. The static experiments were performed to study the effects of various parameters, such as shaking speed, resin dosage and pH during the adsorption process. The results indicate that the effect of external diffusion is eliminated at 160 rpm, the best pH value is 3.0 and the removal percentage of Cr(VI) increases with the increase of the resin dosage. The adsorption of Cr(VI) on KIP210 agrees well with the Langmuir isotherm and the adsorption parameters of thermodynamics are ΔH = 26.5 kJ mol−1, ΔS = 126.7 J mol−1 K−1 and ΔG < 0. It demonstrates that the adsorption of Cr(VI) on KIP210 is a spontaneously endothermic physisorption process. Moreover, the adsorption process can be described well by a pseudo-second-order kinetic model and the activation energy is 30.9 kJ mol−1. The kinetic analysis showed that the adsorption rate is controlled by intraparticle diffusion. The resin is successfully regenerated using the NaOH solutions.  相似文献   

14.
Carbon nanotubes were modified with 8-hydroxyquinoline and used for the removal of Cu(II), Pb(II), Cd(II), and Zn(II) from aqueous solutions. Different instrumentation parameters and methods of development for determining metal ions from aqueous solutions using differential pulse anodic stripping voltammetry were studied. The adsorption of heavy metals from aqueous solution by the pristine and modified MWCNTs was studied kinetically using different kinetic models, and the results showed that the adsorption process best fitted the pseudo-second-order model and the Elovich model. The mechanism of adsorption was explored using the intra-particle diffusion model and the liquid-film model.  相似文献   

15.
This study is concerned with the investigation of the adsorption properties of acrylic acid grafted poly(ethylene terephthalate) fibers by the use of Cu(II) ions in aqueous solutions. Influence of pH, graft yield, contact time, concentration of the ion, and reaction temperature on the amount of ion adsorbed upon reactive fiber were investigated. The time in which the adsorption reached to the equilibrium value was determined as 1 h. The adsorption isotherm of Cu(II) ion was found to be a Langmuir type and the heat of adsorption was calculated as ?10.1 kJ mol?1. It was observed that the adsorbed Cu(II) ion upon acrylic acid grafted poly(ethylene terephthalate) fibers could be recovered in acidic media. The fiber could also readsorb Cu(II) ions without losing its activity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1216–1220, 2003  相似文献   

16.
Adsorption removal of Cu (II) and Pb (II) on cross-linked chitosan/Al13-pillared montmorillonite (CCPM) was examined in solutions. The chitosan dosage was drastically reduced in the new nanocomposite, which is made from the treated clay (Al13-pillared montmorillonite). Several important parameters that influenced the adsorption of Cu (II) and Pb (II) ions, such as cross-linked chitosan-to-clay ratio, pH, temperature, initial concentration, dosage, and contact time effect, were systematically investigated. Result showed that in the nanocomposite with cross-linked chitosan-to-clay ratio of 0.45:1, the maximum removal efficiencies of Cu (II) [pH 6.5, dosage 10 g/L, initial Cu (II) concentration 100 mg/L, contact time 2 h, 298 K] and Pb (II) [pH 6.0, dosage 5 g/L, initial Pb (II) concentration 100 mg/L, contact time 2 h, 298 K] were 96.0% and 99.5%, respectively. Kinetic and isotherm studies have indicated that the adsorption process of Cu (II) or Pb (II) nanocomposites was better fitted by the pseudo-second-order equation and the Freundlich equation, with chemical adsorptions as the rate-limiting step. The metal–ion affinity to the functional groups of CCPM followed the order Pb (II) > Cu (II). The thermodynamic parameters ΔH and ΔS values showed that the sorption process of Cu (II) or Pb (II) was spontaneous (ΔG < 0), was endothermic (ΔH < 0), and had decreased entropy (ΔS < 0). HNO3 (0.1 M) could be a good desorbent in the recovery of metal ions after adsorption and regeneration of the adsorbent.  相似文献   

17.
《分离科学与技术》2012,47(8):1279-1288
A novel low-cost polyvinyl alcohol modified chitosan-mycelium (MCMP) biosorbent was prepared and used for Cu(II) removal from aqueous solutions. SEM, mercury intrusion, and FTIR were employed for characterization. The optimum pH for Cu(II) adsorption was 4–5. Kinetic study showed that Cu(II) adsorption on MCMP followed the pseudo second-order kinetic model. The equilibrium data at different temperatures were well fitted by the Langmuir isotherm. The thermodynamic study proved the spontaneous and endothermic nature of the chemisorption process. MCMP could be reused for 10 adsorption-desorption-regeneration cycles without significantly reducing its adsorption capacity. MCMP adsorption is an inexpensive and promising method for Cu(II) removal from dilute solutions.  相似文献   

18.
A chelating resin, PSGI, was synthesized by the radical polymerization of GMA‐IDA, DVB, and styrene for the removal of Cu(II), Co(II), and Cd(II) from an aqueous solution. The characteristic functional groups and chemical composition of PSGI were analyzed by Fourier transform infrared spectroscopy and elemental analysis of C, H, and N. The equilibrium adsorption capacities of PSGI from their single‐metal ion solutions were 1.46 mmol/g for Cu(II), 1.02 mmol/g for Co(II), and 1.10 mmol/g for Cd(II). The adsorption isothermal of Cu(II) by PSGI followed the Langmuir isotherm. Increasing the concentration (0–0.1 M) of KCl in Cu(II) solution affected the adsorption behavior slightly. Within the pH range of 2–5.5, decreasing the pH of the Cu(II) solution did not produce remarkable changes in the equilibrium adsorption capacities. The adsorption capacities of PSGI for Cu(II) did not cause significant change during the repeated adsorption–desorption operations. The competitive adsorption tests verified that this resin had good adsorption selectivity for Cu(II) with the coexistence of Co(II) and Cd(II). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2123–2130, 2004  相似文献   

19.
A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3-(trimethoxysilyl)propyl] ethylene diamine(TMSPEDA) with epichlorohydrin(ECH) via a sol–gel process.Fourier transform infrared(FTIR) spectra confirmed that the reaction occurred.TGA curves showed that the thermal stability of these hybrid adsorbents reached as high as 180 °C.As a typical example,the adsorption performance of nickel(II) ions onto an adsorbent(the volume ratio of TMSPEDA and ECH was 4:1) was explored.It was found that the adsorption of nickel(II) ions onto this adsorbent followed the Lagergren pseudo-second-order kinetic model.The investigation of the adsorption mechanism demonstrated that nickel(II) adsorption was chiefly controlled by diffusion–chemisorption,suggesting that more diffusion processes were involved in the adsorption of nickel(II) ions onto this type of adsorbents.Desorption experiment indicates that these hybrid adsorbents can be regenerated.These findings reveal that this type of silica-based hybrid adsorbent is promising in the separation and recovery of nickel(II) ions from Ni-containing wastewater or contaminated water.  相似文献   

20.
《分离科学与技术》2012,47(16):2399-2407
A new phenol–formaldehyde based chelating resin containing 4-(2-thiazolylazo) resorcinol (TAR) functional groups has been synthesized and characterized by Fourier transform infrared spectroscopy and elemental analysis. Its adsorption behavior for Cu(II), Pb(II), Ni(II), Co(II), Cd(II), and Mn(II) has been investigated by batch and column experiments. The chelating resin is highly selective for Cu(II) in the pH range 2 ~ 3, whereas alkali metal and alkaline earth metal ions such as Na(I), Mg(II), and Ca(II) are not adsorbed even at pH 6. Quantitative recovery of most metal ions studied in this work except Co(II) is achieved by elution with 2M HNO3 at a flow rate of 0.2 mL min?1. A similar trend is observed for distribution coefficient values. The quantitative separations achieved on a mini-column of chelating resin include Cd(II) – Cu(II), Mn(II) – Pb(II), Co(II) – Cu(II), Mn(II) – Ni(II), and Mn(II) – Co(II) – Cu(II). The recovery of copper(II) is quantitative (98.0–99.0%) from test solutions (10–50 mg/L) by 1 mol/L HNO3-0.01 mol/L EDTA. The chelating resin is stable in acidic solutions below 2.5 M HNO3 or HCl as well as in alkaline solution below pH 11. The adsorption behavior of the resin towards Cu(II) was found to follow Langmuir isotherm and second order rate.  相似文献   

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