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1.
In this article we report a new chelating fiber that was prepared from a hydrolyzate of poly(N‐vinylformamide/acrylonitrile) by a wet‐spinning method. This fiber contains chelating groups, such as amidine groups, amino groups, cyano groups, and amide groups, with high densities. We examined the chelating abilities for several metal ions with this fiber, and present the morphological merit of the fibrous product compared with the globular resin. Based on the research results, it is shown that the fiber has higher binding capacities and better adsorption properties for heavy metal ions than the resin. The pH value of the metal ion solution shows strong influences on the adsorption of the metal ions. The maximum adsorption capacities of the fiber for Cu2+, Cr3+, Co2+, Ni2+, and Mn2+ are 112.23, 88.11, 141.04, 108.06, and 73.51 mg/g, respectively. In mixed metal ions solution, the fiber adsorbs Cr3+, Cu2+ and Co2+ efficiently. The adsorbed metal ions can be quantitatively eluted by hydrochloric acid. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1378–1386, 2002  相似文献   

2.
An ion‐exchange resin containing carboxylic acid groups was prepared by reaction of epoxidized soybean oil with triethylene tetramine, followed by hydrolysis of glycerides by using sodium hydroxide solution. The cation exchange capacity of the resins was determined to be 3.50 mequiv/g. The adsorption capacity for Cu2+, Ni2+, and Co2+ on the obtained resin at pH 5.0 was found to be 192, 96, and 78 mg/g, respectively. Effect of pH on the adsorption capacity for copper (II), nickel (II), and cobalt (II) ions were also studied. Cu2+, Ni2+, and Co2+ were adsorbed at a pH above 3. These metal ions adsorbed on the resin are easily eluted by using 1N HCl solution. The selectivity of the resin for Cu2+ from mixtures containing Cu2+/Co2+/Ni2+ ions in the presence of sodium chloride was also investigated © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2386–2396, 2002  相似文献   

3.
Hydrophilic thermosensitive copolymer beads having phosphinic acid groups were prepared by suspension copolymerization of acryloyloxypropyl n‐octylphosphinic acid (APPO), N‐isopropyl acrylamide (NIPAAm), and tetraethyleneglycol dimethacrylate (4G). The thermosensitivity and the adsorption ability of the copolymer beads for metal ions beads were studied. The APPO‐NIPAAm‐4G copolymer beads were obtained in a good yield by suspension copolymerization of monomers (APPO, NIPAAm, and 4G) dissolved in chloroform, in a saturated Na2SO4 aqueous solution in the presence of surfactant and MgCO3. The APPO‐NIPAAm‐4G copolymer beads had higher adsorption ability for lanthanide metal ions (Eu3+, Sm3+, Nd3+, or La3+) than for main transition metal ions (Cu2+, Ni2+, or Co2+). Furthermore, it was also found that the APPO‐NIPAAm‐4G copolymer beads had selective adsorption ability between lanthanide metal ions, and the order of adsorption ability for lanthanide metal ions was as follows: Eu3+ > Sm3+ > Nd3+ > La3+. The selective adsorption for these metal ions from their mixed solutions was performed by both a batch method and a column method. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 449–460, 2006  相似文献   

4.
The aim of this study is to investigate in detail the feasibility of poly(2‐hydroxyethyl methacrylate‐N‐methacryloyl‐(L )‐histidine methyl ester), PHEMAH membranes for purification of immunoglobulin G (IgG) from human plasma. PHEMAH membranes were prepared by photo‐polymerization technique. Then, Zn2+, Ni2+, Co2+, and Cu2+ ions were chelated directly on the PHEMAH membranes. Elemental analysis assay was performed to determine the nitrogen content and polymerized MAH was calculated as 168.5 μmol/g. The nonspecific IgG adsorption onto the plain PHEMA membranes was negligible (about 0.25 mg/mL). A remarkable increase in the IgG adsorption capacities were achieved from human plasma with PHEMAH membranes (up to 68.4 mg/mL). Further increase was observed with the metal‐chelated PHEMAH membranes (up to 118 mg/mL). The metal‐chelate affinity membranes allowed the one‐step separation of IgG from human plasma. The binding range of metal ions for surface histidines from human plasma followed the order: Cu2+ > Ni2+ > Zn2+ > Co2+. Adsorbed IgG was eluted using 250 mM EDTA with a purity of 94.1%. IgG molecules could be repeatedly adsorbed and eluted with the metal‐chelated PHEMAH membranes without noticeable loss in their IgG adsorption capacity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

5.
《分离科学与技术》2012,47(14):3123-3139
Abstract

An electron beam grafted adsorbent was synthesized by post irradiation grafting of acrylonitrile (AN) on to a non‐woven thermally bonded polypropylene (PP) sheet using 2 MeV electron beam accelerator. The grafted poly(acrylonitrile) chains were chemically modified to convert a nitrile group to an amidoxime (AMO) group, a chelating group responsible for metal ion uptake from an aqueous solution. The effect of various experimental variables viz. dose, dose rate, temperature, and solvent composition on the grafting extent was investigated. PP grafted with the amidoxime group (AMO‐g‐PP) was tested for its suitability as an adsorbent for removal of heavy metal ions such as Co2+, Ni2+, Mn2+, and Cd2+ from aqueous solution. Langmuir and Freundlich adsorption models were used to investigate the type of adsorption of these ions. The adsorption capacities of the adsorbent for the metal ions were found to follow the order Cd2+>Co2+>Ni2+>Mn2+. The kinetics of adsorption of these ions indicated that the rate of adsorption of Cd2+ was faster than that of other ions studied.  相似文献   

6.
The chelating polymer-bearing triazolylazophenol moiety as the functional group was synthesized, its metal adsorption properties for 6 divalent heavy metal ions; Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Pb2+ were investigated. The capacity of the polymer for Cu2+ achieved 8.7 mEq/g in pH 5.3 solution. The polymer showed remarkable color changes from orange to red violet or blue violet with its chelations to the heavy metal ions. The metal adsorption rates of the polymer were rapid in performing complete capacity saturation of heavy metal ions in about 30 min. The capacities varied little the presence of alkali or alkaline earth metal ions in solutions. The perfect elimination of metals from the polymer–M2+ chelates were performed with mineral acid solutions. The metal ions; Cu2+ and Ni2+ in plating-process solutions were effectively removed by the chelating polymer, and the polymer can be practically used for the removal of these ions from waste water.  相似文献   

7.
We modified microporous polyamide hollow fibers by acid hydrolysis to amplify the reactive groups and subsequent binding of Cibacron Blue F3GA. Then, we loaded the Cibacron Blue F3GA‐attached hollow fibers with different metal ions (Cu2+, Ni2+, and Co2+) to form the metal chelates. We characterized the hollow fibers by scanning electron microscopy. The effect of pH and initial concentration of human serum albumin (HSA) on the adsorption of HSA to the metal‐chelated hollow fibers were examined in a batch system. Dye‐ and metal‐chelated hollow fibers had a higher HSA adsorption capacity and showed less nonspecific protein adsorption. The nonspecific adsorption of HSA onto the polyamide hollow fibers was 6.0 mg/g. Cibacron Blue F3GA immobilization onto the hollow fibers increased HSA adsorption up to 147 mg/g. Metal‐chelated hollow fibers showed further increases in the adsorption capacity. The maximum adsorption capacities of Co2+‐, Cu2+‐, and Ni2+‐chelated hollow fibers were 195, 226, and 289 mg/g, respectively. The recognition range of metal ions for HSA from human serum followed the order: Ni(II) > Cu(II) > Co(II). A higher HSA adsorption was observed from human serum (324 mg/g). A significant amount of the adsorbed HSA (up to 99%) was eluted for 1 h in the elution medium containing 1.0M sodium thiocyanide (NaSCN) at pH 8.0 and 25 mM ethylenediaminetetraacetic acid at pH 4.9. Repeated adsorption–desorption processes showed that these metal‐chelated polyamide hollow fibers were suitable for HSA adsorption. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3346–3354, 2002  相似文献   

8.
The aim of this research was to prepare magnesium ferrite (MgFe2O4) magnetic nanoparticles and to investigate their sorption characteristics towards Mn2+, Co2+, Ni2+, Cu2+ ions in aqueous solution. MgFe2O4 was synthesized by glycine-nitrate combustion method and was characterized by low crystallinity with crystallite size of 8.2?nm, particle aggregates of 13–25?nm, BET surface area of 14?m2/g and pore size of 8.0?nm. Sorption properties of MgFe2O4 towards Mn2+, Co2+, Ni2+, Cu2+ ions were studied using one-component model solutions and found to be dependent on metal ions concentration, contact time, pH and conditions of regeneration experiment. The highest sorption capacity of MgFe2O4 was detected towards Co2+ (2.30?mmol?g1) and Mn2+ (1.56?mmol?g?1) and the lowest towards Ni2+ (0.89?mmol?g?1) and Cu2+ (0.46?mmol?g?1). It was observed that sorption equilibrium occurs very quickly within 20–60?min. The pHzpc of sorbent was calculated to be 6.58. At studied pH interval (3.0–7.0) the sorption capacity of MgFe2O4 was not significantly affected. Regeneration study showed that the metal loaded sorbent could be regenerated by aqueous solution of 10?3 M MgCl2 at pH 6.0 within 120?min of contact time. Regeneration test suggested that MgFe2O4 magnetic sorbent can be efficiently used at least for four adsorption-desorption cycles. The high sorption properties and kinetics of toxic metal ion sorption indicates good prospects of developed sorbent in practice for wastewater treatment.  相似文献   

9.
《分离科学与技术》2012,47(15):3770-3791
Abstract

The present study reports the potential of mango peel waste (MPW) as an adsorbent material to remove Cu2+, Ni2+, and Zn2+ from constituted metal solutions and genuine electroplating industry wastewater. Heavy metal ions were noted to be efficiently removed from the constituted solution with the selectivity order of Cu2+ > Ni2+ > Zn2+. The adsorption process was pH-dependent, while the maximum adsorption was observed to occur at pH 5 to 6. Adsorption was fast as the equilibrium was established within 60 min. Maximum adsorption of the heavy metal ions at equilibrium was 46.09, 39.75, and 28.21 mg g for Cu2+, Ni2+, and Zn2+, respectively. Adsorption data of all the three metals fit well the Langmuir adsorption isotherm model with 0.99 regression coefficient. Release of alkali and alkaline earth metal cations (Na+, K+, Ca2+, Mg2+) and protons H+ from MPW, during the uptake of Cu2+, Ni2+, and Zn2+, and EDX analysis of MPW, before and after the metal sorption process, revealed that ion exchange was the main mechanism of sorption. FTIR analysis showed that carboxyl and hydroxyl functional groups were involved in the sorption of Cu2+, Ni2+, and Zn2+. MPW was also shown to be highly effective in removing metal ions from the genuine electroplating industry effluent samples as it removed all the three metal ions to the permissible levels of discharge legislated by environment protection agencies. This study indicates that MPW has the potential to effectively remove metal ions from industrial effluents.  相似文献   

10.
The adsorption isotherms of M2+ ions (M2+ = Ni2+, Co2+, Cd2+, Zn2+ and Mn2+) on the K+-form of δ-MnO2, at pH 6 and at different temperatures, fitted the Langmuir equation and an apparent heat of adsorption, Q, was found to be - 78, - 33, - 34, - 19 and - 15 kJ mol?1 respectively. The adsorption capacity of δ-MnO2 increased in the series: Ni2+ < Co2+ < Cd2+ ± Zn2+ < Mn2+. This was nearly the order of decrease in the radii, r′, of the hydrated ions, estimated from hydration enthalpies. An ionexchange mechanism between hydrated K+ ions in the outer Helmholtz layer and hydrated M2+ ions in the solution, suggests positive entropy contributions which offset the endothermic Q. The proposed mechanism is in agreement with the observed sequence of adsorption capacity and with the decrease in Q in the above series, except for Co2+ adsorption (possibly complicated by the oxidation of Co2+ by δ-MnO2). The adsorption of the cations is probably accompanied by the exchange with Mn ions from the solid. There was evidence of specific adsorption below the point of zero charge (pH 3.3). The adsorption isotherms of Mn2+ ions at pH 7 were higher than those at pH 6 and Q was found to be - 19 kJ mol?1. As the ionic strength increased, the adsorption isotherm of Mn2+ ions at pH 7 and 298 K shifted to lower values. Adsorption isotherms of Cu(II)ions at pH 3.5 and of Fe(III) at pH 2 represent specific adsorption and Q was found to be - 74 and - 13 kJ mol?1 respectively.  相似文献   

11.
In photo-induced graft copolymerization of methyl methacrylate onto cellulose, the effect of metallic ions as sensitizer was investigated. Some metallic ions were effective in their adsorbed states and accelerated the formation of grafts in the order Fe2+ > Ag+ > Fe3+. However, Cu2+ acted negatively, and little effect was observed for Co2+, Ni2+, Mn2+, Zn2+, and Cr3+. In the systems in which aqueous metallic salt solutions were added, the formation of grafts was generally depressed, but Fe3+ was an exception. The effect of metallic ions on the scission reaction of cellulose main chains did not necessarily agree with the effect on the formation of grafts. This is attributed to the varied interaction between cellulose and the different active species produced by irradiation, depending on the type of metallic ions used.  相似文献   

12.
《分离科学与技术》2012,47(7):1057-1073
ABSTRACT

The ion-exchange properties of amorphous aluminum phosphate have been studied in aqueous electrolyte solutions of KCl over a temperature range of 300–320 K. The data were explained by the law of mass action. Sorption of Cu2+, Ni2+, and Co2+ on AIPO4 was also studied as a function of temperature and concentration, and the data were fitted to Langmuir adsorption equations. In all cases the adsorption was found to increase with increases in temperature and concentration in the selectivity order Cu2+ > Co2+ > Ni2+. Further, the values of Langmuir constants were used to calculate the thermodynamic parameters δS°, δH°, and δG°.  相似文献   

13.
Sequestration and removal of heavy metal ions from aqueous solutions pose multiple challenges. Ease of synthesis, high adsorption capacity and ease of regeneration are important considerations in the design of polymeric adsorbent materials developed for this purpose. To meet this objective, a new approach was used to design and synthesize a highly porous polystyrene-based resin (IDASR15) bearing iminodiacetate functional groups in every repeat unit by free radical polymerization with N, N'-methylenebisacrylamide as crosslinker followed by base hydrolysis. The physiochemical chemical properties of the resin were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, equilibrium swelling value (ESV) and thermogravimetric analysis. Metal uptake capacity of IDASR15 towards low concentrations of various toxic heavy metal ions such as Cu2+, Cd2+, Mn2+, Zn2+, Pb2+, Ni2+, Co2+, Co3+, Cr3+, Fe2+, Fe3+, and Al3+ were investigated from their aqueous solution by batch method and found to be 0.943–2.802 mmol/g. The maximum capacity was 2.802 mmol/g obtained for Cu2+ ion at pH 5. The potential for regeneration and reuse has been demonstrated with Cu2+ ion by batch and column methods. The reported results suggest that IDASR15 is a highly efficient and porous complexing agent for commonly found toxic metal ions in aqueous streams with a high ESV of 68.55 g of water/1.0 g of IDASR15. It could also be reused ~99.5% of adsorption efficiency which is very promising and holds significant potential for waste-water treatment applications.  相似文献   

14.
Cation-exchange adsorbents were prepared by radiation-induced grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) fabric and polyethylene (PE) hollow fiber and subsequent phosphonation of epoxy groups of poly(GMA) graft chains. The adsorption characteristics of Pb2+, Cu2+ and Co2+ for the two cation-exchange adsorbents were studied. In the grafting of GMA onto PP fabric, the degree of grafting (%) increased with an increase in reaction time, reaction temperature, and pre-irradiation dose. The maximum grafting yield was observed around 60% GMA concentration. In 50, 130 and 250% GMA-grafted PP fabric, the content of phosphoric acid was 1.52, 3.40 and 4.50 mmol/g at 80 °C in the 85 % phosphoric acid aqueous solution for 24 h, respectively. The adsorption of Pb2+, Cu2+ and Co2+ by PP fabric adsorbent was enhanced with an increased phosphoric acid content The order of adsorption capacity of the PP fabric adsorbent was Pb2+>Co2+>Cu2+. In adsorption of Pb2+, Cu2+ and Co2+ by PE hollow fiber, the amount of Pb2+ adsorbed by the PE hollow fiber adsorbent containing 1.21 mmol/g of -PO3H wasca. 54.4 g per kg. The adsorption amount of Cu2+ and Co2+ in the same PE hollow fiber wasca. 21.0 g per kg andca. 32.1 g per kg, respectively. The order of adsorption of the PE hollow fiber adsorbent was Pb2+>Co2+>Cu2+.  相似文献   

15.
The macroreticular chelating resins containing both polyethylenepolyamine side chains and mercapto groups were prepared by the reaction of 2,3-epithiopropyl methacrylate-divinylbenzene macroreticular copolymer beads with polyethylene-polyamine. The adsorption behavior of metal ions on the obtained resins was then investigated. The amination of the macroreticular copolymer beads could effectively be carried out by treatment of the polymer beads with polyethylenepolyamine in organic solvent (benzene, terahydrofuran) or in the absence of organic solvent at 80°C or 100°C for 60 min. It was found that the adsorption capacity of the resins for metal ions is not only affected by the ion exchange capacity of the resins but also by the porosity of the resins. Hg2+, Ag+, and Cu2+ were effectively adsorbed on the resins even at a pH below 3, whereas Co2+, Ni2+, and Cd2+ were adsorbed at a pH above 3, Mn2+ at a pH above 7, and Ca2+ at a pH above 8. These metal ions adsorbed on the resins could easily be eluted with dilute mineral acid solution or dilute mineral acid solution containing thiourea.  相似文献   

16.
It is demonstrated through the electrochemical reduction of cobalt manganese spinels that it is possible to increase the cathodic reactivity by replacement of cobalt ions by nickel and copper cations. The reduction reaction occurs on active sites formed by Mn4+ ions associated, in octahedral sites, with Mn3+ ions, for the NixCo1 ? x Mn2O4 compounds. For the copper manganites oxides, CuxCo1 ? xMn2O4, the electrochemical reaction is likely to occur by the redox on solid state between Mn3+ and Cu2+ cations.  相似文献   

17.
Four kinds of amino-group-containing chelating fibers were prepared by reacting diethylenetriamine, diethanolamine, diethylamine, and aminopyridine, respectively, with a grafted fiber PVA-g-GMA containing epoxy groups. The γ-ray preirradiation initiated graft copolymerization of GMA onto PVA fiber, the functionalization of the grafted fiber PVA-g-GMA with amino compounds, and the adsorption properties of the obtained chelating fibers were systematically investigated. It is concluded that with increasing monomer concentration, reaction time, and temperature, the grafting percentage increases significantly. In the functionalization of the grafted fiber, reaction time, temperature, solvent, and amount of amine used greatly influence the reaction. 1,4-Dioxane is a reasonable solvent for the reaction. The chelating fibers present great adsorption amounts and high adsorption rates for Cu2+ ion and Au3+ ion. Among the chelating fibers, the fiber with diethylenetriamine group is the most reasonable chelating fiber for the adsorption of Cu2+ and Au3+. The chelating fibers present good selectivities for Cu2+ in the solution with Cu2+, Mn2+, Ni2+, Co2+, and Zn2+, while presenting quite high selectivities for Au3+ ion in the solution with Cu2+, Au3+, Zn2+, and Cr3+ ions. The chelating fiber with diethanolamine or diethylamine can reduce the adsorbed Au3+ into metallic gold. © 1994 John Wiley & Sons, Inc.  相似文献   

18.
The effects of metal ions on the biodegradation of benzene and toluene were investigated. Among 12 tested metal ions, Cu2+, Ni2+, Co2+ and A+ g inhibited the degradation of benzene and toluene severely byAlcaligenes xylosaxidans Y234. Cu2+ was found to inhibit catechol 1,2-dioxygenase in the degradation of benzene and toluene. Co2+ and Ni2+ were supposed to inhibit benzoate 1,2-dioxygenase, while Ag+ was supposed to inhibit benzaldehyde dehydrogenase in the degradation of toluene. The inhibition effect caused by these metal ions could be overcome both by microbial adaptation and by adding specific aromatic compounds to the broth.  相似文献   

19.
Single and binary metal systems were employed to investigate the removal characteristics of Pb2+, Cu2+, Cd2+, and Zn2+ by Chlorella sp. HA-1 that were isolated from a CO2 fixation process. Adsorption test of single metal systems showed that the maximum metal uptakes were 0.767 mmol Pb2+, 0.450 mmol Cd2+, 0.334 mmol Cu2+ and 0.389 mmol Zn2+ per gram of dry cell. In the binary metal systems, the metal ions on Chlorella sp. HA-1 were adsorbed selectively according to their adsorption characteristics. Pb2+ ions significantly inhibited the adsorption of Cu2+, Zn2+, and Cd2+ ions, while Cu2+ ions decreased remarkably the metal uptake of Cd2+ and Zn2+ ions. The relative adsorption between Cd2+ and Zn2+ ions was reduced similarly by the presence of the other metal ions.  相似文献   

20.
A conventional free‐radical initiating process was used to prepare graft copolymers from acrylonitrile (AN) with corn‐cob cellulose with ceric ammonium nitrate (CAN) as an initiator. The optimum grafting was achieved with corn‐cob cellulose (anhydroglucose unit, AGU), mineral acid (H2SO4), CAN, and AN at concentrations of 0.133, 0.081, 0.0145, and 1.056 mol/L, respectively. Furthermore, the nitrile functional groups of the grafted copolymers were converted to amidoxime ligands with hydroxylamine under basic conditions of pH 11 with 4 h of stirring at 70°C. The purified acrylic polymer‐grafted cellulose and polyamidoxime ligand were characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy analysis. The ligand showed an excellent copper binding capacity (4.14 mmol/g) with a faster rate of adsorption (average exchange rate = 7 min), and it showed a good adsorption capacity for other metal ions as well. The metal‐ion adsorption capacities of the ligand were pH‐dependent in the following order: Cu2+ > Co2+ > Mn2+ > Cr3+ > Fe3+ > Zn2+ > Ni2+. The metal‐ion removal efficiency was very high; up to 99% was removed from the aqueous media at a low concentration. These new polymeric chelating ligands could be used to remove aforementioned toxic metal ions from industrial wastewater. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40833.  相似文献   

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