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1.
Hydroxybenzoic acid group has been incorporated onto guar gum by modified Porath's method of functionalization of polysaccharides. The newly synthesized guar gum 4‐hydroxybenzoic acid (GHBA) resin was characterized by Fourier‐transform infrared spectroscopy, elemental analysis, ion‐exchange capacity, column reusability, and physicochemical properties. The distribution coefficient (Kd) values and effect of pH on chelation of these metal ions using batch method were studied. The separations of mixture of Fe2+, Zn2+, Cu2+, Cd2+, and Pb2+ metal ions on GHBA resin on the basis of their distribution coefficient at various pH were also achieved using column chromatography. The effect of experimental parameters such as pH, treatment time, agitation speed, temperature, adsorbent dose, initial metal ion concentration, and flow rate on the removal of metal ions has been also studied. GHBA resin is effective adsorbents for the removal of different toxic metal ions from aqueous solutions and follows the order: Fe2+ > Zn2+ > Cu2+ > Cd2+ > Pb2+. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers  相似文献   

2.
A generalized theoretical model for the measurement of effective diffusion coefficients of heterovalent ions in macroporous ion-exchange resins by the zero-length column method was developed. The model includes the resistance to mass transfer both in the particle and in the film and described ion fluxes with Nernst-Planck equations. Equilibrium was described using the Langmuir type empirical equation. The values of intraparticle diffusivity of Cu2+, Cd2+, Zn2+, and H+ on commercial Lewatit TP-207 were obtained by non-linear regression, these values agree fairly well with data reported previously in literature. The following trend was observed: DCu>DZn>DCd.  相似文献   

3.
ABSTRACT

The ion exchange of trace amounts of Cu2+, Zn2+ and Pb2+ with the hydrogen-form of hydrated ferric oxide as a function of nitric acid concentration has been studied at 25, 30,35 and 60°C. Ion exchange of these cations increases with increasing temperature in the investigated temperature range. From these results, equilibrium constants for the Cu2+/H+, Zn2+/H+ and Pb2+/H+ ion exchange on hydrated ferric oxide and thermodynamic quantities for these reactions were calculated, and some predictions made for the exchange process taking place in this material. The selectivity series is Zn2+ > Cu2+ > Pb2+.  相似文献   

4.
ABSTRACT

Experiments of binary and ternary ion exchange equilibrium of heavy metals and sodium were carried out in a complexing iminodiacetic resin Lewatit TP 207. First, binary equilibrium data were obtained at different temperatures and ionic strength and fixed to models considering two different ion exchange stoichiometrics. For ternary equilibrium data, two distinct simple models were applied. One to be applied to systems showing very different selectivity for the metals (for instance, Cu2+/Co2+/Na+) and the other for systems with similar selectivity for the metals (such as Zn2+/Co2+/Na+). The ternary equilibrium data obtained is presented in this work and fitted using the two above mentioned models. These models allow us to obtain the equilibrium parameters for binary and ternary system to be used in the design of equipment using this iminodiacetic resin.  相似文献   

5.
The sorption properties of the commercially available cationic exchange resin, Amberlite IRC‐718, that has the iminodiacetic acid functionality, toward the divalent metal‐ions, Fe2+, Cu2+, Zn2+, and Ni2+ were investigated by a batch equilibration technique at 25°C as a function of contact time, metal ion concentration, mass of resin used, and pH. Results of the study revealed that the resin exhibited higher capacities and a more pronounced adsorption toward Fe2+ and that the metal‐ion uptake follows the order: Fe2+ > Cu2+> Zn2+ >Ni2+. The adsorption and binding capacity of the resin toward the various metal ions investigated are discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

6.
Ion exchange has a great potential to remove heavy metals from industrial wastewaters or heavy metal-containing sludge. In order to design and operate heavy metal removal processes, the equilibrium relationship between ions and resin must be known a prior. A series of ion-exchange equilibrium tests of Cu2+/H+, Zn2+/H+, and Cd2+/H+ systems using Amberlite IR-120 were performed. The equilibrium data were analyzed by the Langmuir isotherm, Freundlich isotherm, and selectivity coefficient approaches. The thermodynamic parameters such as Gibbs free energy change, enthalpy change, and entropy change were calculated. By comparison of the selectivity coefficients, the affinity sequence to IR-120 is Cu2+ > Zn2+ > Cd2+ > H+. Moreover, in order to understand the heavy metal extraction kinetics in the presence of Amberlite IR-120, the ion-exchange kinetics was also studied. The ion-exchange kinetic data were regressed by the pseudo first-order, second-order models, and a reversible reaction model. The activation energies calculated from the rate coefficients at different temperatures are 15.41, 7.04, and 17.01 kJ/mol for copper, zinc, and cadmium, respectively. Although the pseudo first- and second-order models are easier to use for data analysis, the resultant model parameters depend on operating conditions. The reversible reaction model is capable to predict the effects of resin to solution ratio, initial heavy metal concentration, and temperature on the ion-exchange kinetic curves.  相似文献   

7.
Poly(2‐acrylamido glycolic acid‐co‐2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) [P(AGA‐co‐APSA)] was synthesized by radical polymerization in an aqueous solution. The water‐soluble polymer, containing secondary amide, hydroxyl, carboxylic, and sulfonic acid groups, was investigated, in view of their metal‐ion‐binding properties, as a polychelatogen with the liquid‐phase polymer‐based retention technique under different experimental conditions. The investigated metal ions were Ag+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+, and Cr3+, and these were studied at pHs 3, 5, and 7. P(AGA‐co‐APSA) showed efficient retention of all metal ions at the pHs studied, with a minimum of 60% for Co(II) at pH 3 and a maximum close to 100% at pH 7 for all metal ions. The maximum retention capacity (n metal ion/n polymer) ranged from 0.22 for Cd2+ to 0.34 for Ag+. The antibacterial activity of Ag+, Cu2+, Zn2+, and Cd2+ polymer–metal complexes was studied, and P(AGA‐co‐APSA)–Cd2+ presented selective antibacterial activity for Staphylococcus aureus with a minimum inhibitory concentration of 2 μg/mL. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

8.
This article reports the synthesis, characterization, and ion exchange properties of a terpolymer. The terpolymer resin salicylic acid‐diaminonaphthalein‐formaldehyde (SDNF) was synthesized by the condensation of salicylic acid and diaminonaphthalein with formaldehyde in the presence of a hydrochloric acid catalyst. Terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance spectroscopy, and UV–Visible spectral studies. The number average molecular weight of the resin was determined by nonaqueous conductometric titration. Chelation ion exchange properties have also been studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+ ions employing a batch equilibrium method. It was employed to study the selectivity of metal ion uptake involving the measurements of distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over wide pH range and in a media of various ionic strengths. The terpolymer showed higher selectivity for Fe3+, Cu2+, and Ni2+ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

9.
A novel polymeric ligand having 2,2′:6′,2″‐terpyridine as pendant group was prepared through a Williamson type etherification approach for the reaction between 4′‐hydroxy‐2,2′: 6′,2″‐terpyridine and the commercially available 4‐chloromethyl polystyrene. The chelating properties of the new polymer toward the divalent metal ions (Cu2+, Zn2+, Ni2+, and Pb2+) in aqueous solutions was studied by a batch equilibration technique as a function of contact time, pH, mass of resin, and concentration of metal ions. The amount of metal‐ion uptake of the polymer was determined by using atomic absorption spectrometry. Results of the study revealed that the resin exhibited higher capacities and a more pronounced adsorption toward Pb2+ and that the metal‐ion uptake follows the order: Pb2+ > Cu2+ > Zn2+ > Ni2+. The adsorption and binding capacity of the resin toward the various metal ions investigated are discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
《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   

11.
A new chelating ion‐exchange resin containing the hydroxamic acid functional group was synthesized from poly(methyl acrylate) (PMA)‐grafted sago starch. The PMA grafted copolymer was obtained by a free‐radical initiating process in which ceric ammonium nitrate was used as an initiator. Conversion of the ester groups of the PMA‐grafted copolymer into hydroxamic acid was carried out by treatment of an ester with hydroxylamine in an alkaline solution. The characterization of the poly(hydroxamic acid) chelating resin was performed by FTIR spectroscopy, TG, and DSC analyses. The hydroxamic acid functional group was identified by infrared spectroscopy. The chelating behavior of the prepared resin toward some metal ions was investigated using a batch technique. The binding capacities of copper, iron, chromium, and nickel were excellent and the copper capacity was maximum (3.46 mmol g−1) at pH 6. The rate of exchange of the copper ion was very fast that is, t1/2 < 5 min. It was also observed that the metal ion‐sorption capacities of the resin were pH‐dependent and its selectivity toward the metal ions used is in the following order: Cu2+ > Fe3+ > Cr3+ > Ni2+ > Co2+ > Zn2+ > Cd2+ > As3+ > Pb2+. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1256–1264, 2001  相似文献   

12.
A generalized theoretical model for the measurement of effective diffusion coefficients of heterovalent ions in ion exchange resins by the zero-length column method was developed. The model included the resistance to mass transfer both in the particle and in the film and described ion fluxes with Nernst-Planck equations. Equilibria were described using a model based on the mass action law. The values of intraparticle diffusivity of Cu2+, Cd2+, Zn2+, and H+ on commercial Amberlite IR-120 were obtained by non-linear regression, these values agree fairly well with data reported previously in literature. The following trend was observed: DCu>DZn>DCd.  相似文献   

13.
《分离科学与技术》2012,47(8):2117-2143
Abstract

The aim of this work is to study the effectiveness of regional, low-cost natural clinoptilolitic zeolite tuff in heavy metal ions removal from aqueous solution, through comparative study with commercial granulated activated carbon. The equilibrium of adsorption of Cd2+, Pb2+, and Zn2+ on both adsorbents have been determined at 25, 35, and 45°C in batch mode. The granulated activated carbon has shown around three times higher adsorption capacity for Cd2+ and Zn2+ than natural zeolite, and almost the same adsorption capacity for Pb2+ as the natural zeolite. The metal ion selectivity series Pb2+ > Cd2+ > Zn2+, on a mass basis, has been obtained on both adsorbents. The Langmuir and Freundlich model have been used to describe the adsorption equilibrium. The thermodynamic parameters were calculated from the adsorption isotherm data obtained at different temperatures. The study of the influence of the acidity of the metal ion aqueous solution has shown an increase of metal ion uptake with increase of the pH. The sorption mechanism of Cd2+, Pb2+, and Zn2+ on natural zeolite changes from ion-exchange to ion-exchange and adsorption of metal-hydroxide with increase of the pH from 2 to 6 (and 7 for Zn2+). The preliminary cost calculation, based on adsorbents maximum adsorption capacity and their price, have revealed the potential of natural zeolite as an economic alternative to the granulated activated carbon in the treatment of heavy metal polluted wastewater.  相似文献   

14.
Amberlite XAD‐2 has been functionalized by coupling through –SO2‐with ethylenediamine, propylenediamine, and diethylenetriamine to give the corresponding polyamine chelating resins I–III. The solid metallopolymer complexes of the synthesized chelating resins with Cu2+, Zn2+, Cd2+, and Pb2+ were synthesized. The polyamine derivatives and their metal complexes were characterized by elemental analysis, spectral (IR, UV/V, and ESR), and magnetic studies. The batch equilibrium method was utilized for using the chelating polyamines for the removal of Cu+2, Zn+2, Cd+2, and Pb+2 ions from aqueous solutions at different pH values and different shaking times at room temperature. The selective extraction of Cu+2 from a mixture of the four metal ions and the metal capacities of the chelating resins were evaluated using atomic absorption spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1839–1846, 2005  相似文献   

15.
The chelation behavior of poly(β‐diketone), polymer I, and poly(β‐diketone) oxime, polymer II, toward the divalent metal ions, Cu2+, Zn2+, Ni2+, and Cd2+, and the trivalent lanthanide metal ions, La3+, Nd3+, Sm3+, Gd3+, and Tb3+ was investigated by a batch equilibration technique as a function of contact time, pH, and counter ion. Polymer II exhibited improved chelation characteristics toward lanthanide metal ions in comparison with polymer I and the metal‐ion uptake follows the order Tb3+ ≈ Gd3+ ≈ Sm3+ > Nd3+ ≈ La3+. On the other hand, polymer I showed relatively higher capacity than polymer II, toward the investigated divalent metal ions, where the metal‐ion uptake follows the order Cu2+ > Cd2+ ≈ Zn2+ > Ni2+. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

16.
Chromatographic column separations of toxic metal ions from industrial wastewater were achieved in acid media at optimized (Kd) values with a synthesized cation exchange TABA resin. The prepared TABA resin was characterized by FTIR, elemental, and thermogravimetric analysis. Studies of total ion exchange capacity, resin durability, and swelling were carried out. The distribution coefficient values of metal ions, viz Cu2+, Fe2+, Zn2+, Cd2+ and Pb2+ at different pH, were also studied using a batch equilibration method. The different factors affecting metal ions adsorption on this substrate, such as treatment time, agitation speed, and temperature, were studied in detail.  相似文献   

17.
A copolymer (4‐HAOF) prepared by condensation of 4‐hydroxyacetophenone and oxamide with formaldehyde in the presence of an acid catalyst proved to be a selective chelating ion‐exchange copolymer for certain metals. Chelating ion‐exchange properties of this copolymer were studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+, and Hg2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal‐ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+ ions than for Co2+, Zn2+, Cd2+, Pb2+, Cu2+, Ni2+, and Hg2+ ions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 787–790, 2003  相似文献   

18.
Abstract

Salinity and low temperature effects on adsorption of contaminant metals from water using an iminodiacetic acid (IDA) ion‐exchange resin, were investigated under dynamic flow conditions. The order of selectivity of the resin (20°C and 0% seawater) was: Cu2+> Pb2+> Cr3+> Ni2+>Cd2+>Zn2+. Low temperature (4°C) had no significant effect on the selectivity of the contaminant metals and salinity only affected selectivity for Cr3+ and Cu2+. Copper had highest selectivity in all column experiments, except where extensive deprotonation occured. Buffering affected retention of Cr3+; possibly due to precipitation or complexation as a result of increase in pH.  相似文献   

19.
Copolymers (8‐HQ5‐SAOF) were synthesized by the condensation of 8‐hydroxyquinoline 5‐sulphonic acid (8‐HQ5‐SA) and oxamide (O) with formaldehyde (F) in the presence of acid catalyst. Four different copolymers were synthesized by using varied molar proportion of the reacting monomers. Copolymer resin composition has been determined on the basis of their elemental analysis and average molecular weights of these resins were determined by conductometric titration in nonaqueous medium. Viscometric measurement in dimethyl sulphoxide (DMSO) has been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, FTIR, and proton nuclear magnetic resonance spectra were studied to elucidate the structures. The newly synthesized copolymer proved to be a selective chelating ion‐exchange copolymer for certain metals. The chelating ion‐exchange properties of this synthesized copolymer was studied for different metal ions such as Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, and Pb2+. A batch equilibrium method was used in the study of the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion only for representative copolymer 8‐HQ5‐SAOF‐I due to economy of space. The study was carried out over a wide pH range, shaking time, and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+, Cu2+, and Ni2+ ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

20.
《分离科学与技术》2012,47(15):2423-2429
ABSTRACT

The effect of H+ ion concentration on the ion-exchange selectivity of Nafion 117 cation-exchange membrane toward Zn2+, Pb2+, Cu2+, Al3+, and Fe3+ have been studied. A selective transport of any particular metal ion was not possible by controlling the pH alone. However, selective permeation of Zn2+ across the membrane could be accomplished by selectively masking the metal ion as the cationic 1,10-phenanthroline complex while the permeation of other interfering ions could be suppressed by masking them as their anionic EDTA complex. About 20% of Zn2+ selectively permeated from the mixture in 6 hours and the quantity increased to 67% after 60 hours of permeation.  相似文献   

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