Chelating Ion Exchange Research Articles

Determination of Pt and Pd in particles emitted from automobile exhaust catalysts using ion-exchange matrix separation and voltammetric detection

We report on the ion-exchange separation of Pt and Pd from the main elements emitted from catalysts of gasoline-fueled cars by exploiting the selective chelating ion exchanger Lewatit MonoPlus TP-214. Pt and Pd were then eluted with a recovery of 92% and 96%, respectively, using an acidified solution of thiourea, and the eluent was analyzed by sequential voltammetry. The detection limits are 0.04 μg L−1 and 1 μg L−1 for Pt and Pd, respectively, and the relative standard deviation is about 4.0% (for n = 10). The procedure was successfully applied to particles emitted from automobile exhaust catalysts of four capacity engine vehicles. Graphite furnace atomic absorption spectrometry was also employed for reasons of comparison. Emission by four vehicles with 1400, 2600, 3200, and 4800 cc engines, respectively, ranged from 19 to 28 ng km−1 for Pt, and from 102 to 150 ng km−1 for Pd.

Decolorization of ammonium lignosulfonate with H2O2/Cu(II) heterogeneous catalyst

The potential of ammonium lignosulfonate (ALS) decolorization and degradation in aqueous solution was studied in a heterogeneous system using hydrogen peroxide and a Cu (II)-chelating ion exchanger. This was based on acrylic copolymers functionalized with N,N dimethylamino propylamine (DMAPA) as a catalyst. In order to optimize the efficiency of the system, the influence of such process parameters like H2O2 concentration, pH, contact time, temperature, ALS concentration and catalyst amount were evaluated. The apparent rate constant of decolorization calculated from the absorbance data indicates that the process profiles follow pseudo-first order kinetics. Lignosulfonate degradation was furthermore studied by FTIR spectroscopy, thermogravimetric analysis and determination in phenolic compounds. The catalyst stability and reusability have also been investigated. Our experimental results clearly indicate that, under optimum conditions, the ammonium lignosulfonate solutions exhibit a total bleaching associated with degradation and significant mineralization to CO2.

Analytical applications of newly synthesized copolymer resin derived from p‐aminophenol, dithiooxamide, and formaldehyde

AbstractA copolymer resin (p‐APDF) has been synthesized using the monomers p‐aminophenol, dithiooxamide, formaldehyde in 1 : 1 : 2M proportions in the presence of 2M HCl as catalyst. The structure of p‐APDF copolymer has been elucidated on the basis of elemental analysis and various physicochemical techniques, i.e., UV‐visible, FTIR, and 1H‐NMR spectroscopy. The number average molecular weight of copolymer resin was determined by nonaqueous conductometric titration in DMF. Viscosity measurement were carried out in DMF indicate normal behavior. The prepared resin proved to be a selective ion exchange resin for some metal ions. The chelating ion exchange properties of this resin was studied for Fe(III) and Cu(II), Ni(II), Co(II), Zn(II), Cd(II), Pb(II) ions. A batch equilibrium method was used to study selectivity of metal ion uptake over a wide pH range and in media of various ionic strength. The resin showed a higher selectivity for Fe(III), Ni(II), Cu(II) ions than for Co(II), Pb(II), Zn(II), and Cd(II) ions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

An eco-friendly synthesis, characterization, morphology and ion exchange properties of terpolymer resin derived from p-hydroxybenzaldehyde

A novel chelating terpolymer resin has been synthesized through the terpolymerization of p-hydroxybenzaldehyde and biuret with formaldehyde (p-HBBF) in 1:1:2mol ratio using hydrochloric acid as a reaction medium by condensation technique. The synthesized terpolymer resin was characterized by elemental analysis, FTIR, 1H NMR and 13C NMR spectroscopy. On basis of the spectral studies, the structure of the terpolymer resin was proposed. The physico-chemical parameters have been evaluated for the terpolymer resin. Non-aqueous conductometric titration was used to determine the average molecular weight and polydispersity of the p-HBBF terpolymer resin and the intrinsic viscosity was also determined. The semicrystalline nature of the synthesized terpolymer was established by scanning electron microscopy (SEM). Terpolymer (p-HBBF) synthesized is proved to be selective chelating ion exchange terpolymer resin for certain metals. Chelating ion exchange properties of this polymer was studied for Fe3+, Cu2+, Cd2+, Zn2+, Ni2+ and Pb2+ ions. A batch equilibrium method was employed in the study of the selectivity of the distribution of a given metal ions between the polymer sample and a solution containing the metal ion. The morphology of the terpolymers was studied by scanning electron microscopy, showing amorphous nature of the resins therefore can be used as a selective ion-exchanger for certain metal ions.

The effect of the presence of metatartaric acid on removal effectiveness of heavy metal ions on chelating ion exchangers

The paper presents experimental results and their evaluation for the sorption of copper(II), zinc(II), cobalt(II) and nickel(II) complexes with metatartaric acid on chelating ion exchangers with different functional groups. The literature lacks the data concerning sorption of heavy metal ions in the presence of metatartaric acid on ion exchangers. The effect of important parameters such as the value of pH, the metal(II) ion and ligand concentration as well as their molar ratio and the type of functional group of the ion exchanger used was studied. It was found that the time of 60 min was sufficient for sorption to attain equilibrium. The equilibrium sorption capacities for copper(II), zinc(II), cobalt(II) and nickel(II) complexes with metatartaric acid were 37.35 mg/g, 32.02 mg/g, 32.78 mg/g and 28.31 mg/g on Lewatit TP 207 and 42.15 mg/g, 34.32 mg/g, 27.76 mg/g and 21.70 mg/g on Lewatit TP 260, respectively. The sorption optimum pH was 7. Temperature does not affect the sorption process significantly. The sorption data were well fitted by the Langmuir adsorption model whereas kinetics of the sorption process was well described by the pseudo second order kinetics equation.

Sequestering of Cd (II) and Ni (II) from aqueous solutions onto chelex 100

The chelating exchange resin Chelex 100, with functional group iminodiacetic acid (IDA), was used to remove Cd (II) and Ni (II) from aqueous solutions. Batch elution experiments using Cd (II) and Ni (II) solutions were compared. Experiments were finally performed at different pH values (2.0–7.0), metal ion concentrations (10–500 mg/l), and resin dose (1 g–15 g/l of metal ion solution), stirring speed (50–250 rpm) and contact time (10–120 min) at 25 ± 5°C. Maximum metal removal was observed at pH 5.0 to 6.0. The removal efficiency of Chelex 100 for Cd (II) and Ni (II) removal were found to be 100% and 82.5% respectively for dilute solutions at 15 g/l resin dose under optimized conditions. The results revealed that Cd (II) and Ni (II) can be considerably removed by chelex 100 and it could be a potential material for the removal of these heavy metals from aqueous systems.

O-Cresol, thiourea and formaldehyde terpolymer – A cation exchange resin

o-Cresol–thiourea–formaldehyde terpolymer resin was synthesized through the condensation of o-cresol and thiourea with formaldehyde in the mole ratio 1:3:5 in the presence of 2 M hydrochloric acid as a catalyst. The resulting copolymer was characterized with IR and 1H NMR spectral data. The average molecular weight of the resin was determined by Gel permeation chromatography. Thermal study of the resin was carried out to calculate the activation energy (Ea), enthalpy of activation (H‡), entropy of activation (S‡), free energy of activation (G‡), and pre-exponential factor (A) of various steps of thermal decomposition of the terpolymer. The Dharwadkar and Kharkhanavala method has been used to calculate thermal activation energy and thermal stability. The chelation ion-exchange properties were also studied with the batch equilibrium method. The chelation ion-exchange properties of the copolymer was studied for Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+ and Cd2+ ions. The resin was proved to be selective chelating ion-exchange copolymer for certain metals. The study was carried out over a wide pH range and in media of various ionic strengths.

Application of Three Agarose Based Chelating Adsorbents for Preconcentration of Some Metal Ions in Water

Properties of two agarose based Chelating ion exchangers with, respectively, dipicolyl amine (DPA) and tris (2-aminoethyl) amine (TREN) as functional groups are investigated and compared to those of a previously studied adsorbent functionalized using iminodiacetic acid (IDA), with the same matrix, for preconcentration of Cu2+, A13+ and Mo3+ in water. Binding capacities, adsorption rates and column recoveries of the metal ions are carefully investigated. An inductively coupled plasma atomic emission spectroscopy (ICPAES) instrument is used for measurements.The capacity of all adsorbents for Cu ions at different pH was similar while, for other metal ions was more variable and pH dependent. The highest capacity of the DPA and TREN sorbents was obtained for copper, which is averaged to 18.3 (±0.3) and 120.0 (±6.0) μmol /mL, respectively. Kinetic studies indicated relatively high adsorption rates of Cu2+ on all the sorbents. Al and Mo, on the other hand, showed relatively high rates on the DPA and TREN chelators. High column recoveries were obtained for Cu and Al ions on the IDA adsorbent and only very low recovery of Mo ion was observed at the studied pHs. The column recoveries for the DPA sorbent, on the other hand, were quite low for Cu and Mo. It indicated high recoveries only for Al, which rose up to 77.9 (±0.6)% at pH 7.3. Copper also was almost quantitatively recovered on the TREN sorbent, with pH dependent recoveries for Al and Mo ions. The method was evaluated by preconcentration of spiked river water samples. Good agreement was obtained between the results obtained for natural samples and standard solutions. In general, more selectivities, slower adsorption rates and lower and more pH dependent recoveries were identified for the DPA and TREN sorbents compared to that with the IDA groups.

Ion Exchange Study of Some New Copolymer Resins Derived from 8‐Hydroxyquinoline‐5‐sulphonic Acid, Biuret and Formaldehyde

Copolymer resins (8‐HQSABF) were synthesized by the condensation of 8‐hydroxyquinoline‐5‐sulphonic acid and biuret with formaldehyde in the presence of hydrochloric acid as catalyst, proved to be selective chelation ion exchange copolymer resins for certain metals. Chelation ion exchange properties to these polymers were studied for Cu2+, Cd2+, Co2+ and Zn2+ ions. A batch equilibrium method was employed in the study of the selectivity of the distribution of a given metal ions between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in a media of various ions strengths. The polymer showed a higher selectivity for Cu2+ ions than for Cd2+, Co2+ and Zn2+ ions. Hence on the basis of above studies these copolymer may be used as semiconductors, surface coating, ion‐exchangers, materials for rechargeable battery cell in various electronic industries, plastic materials, elastomers and in boiler plants

Sorption of bivalent ions by a fibrous chelating ion exchanger and the structure of sorption complexes

Acid–base properties, kinetics and equilibrium sorption of Ca 2+, Cu 2+, Pb 2+, Cd 2+, Ni 2+ and Mn 2+ ions on fibrous chelating ion exchanger FIBAN X-1 containing iminodiacetic group have been studied. The structural and electronic characteristics of ion-polymeric complexes have been obtained by non-empirical quantum chemical calculations. The rate of sorption processes was extremely high; the half-process time of the sorption process was equal to 24 s. The isotherms of ion sorption are described by the Langmuir equation what allowed deriving equation for dependence of the distribution coefficient on the ion concentration and accurate extrapolation of these value to zeros concentration. The concentration range the Henry’s law applicability was determined theoretically and proved experimentally. The sorption selectivity series in a neutral medium was Cu > Ni > Pb > Cd > Mn > Ca. The same series follows the pH at which the sorption begins. Complete extraction of all heavy metal ions occurs at pH > 4. The quantum chemical calculations have shown that the selectivity of sorption is determined by the number of coordination bonds between the cation and fixed anion, the length of the bonds and degree of their covalence. The way of combining of these factors is individual for each specific cation and can be revealed by quantum chemical calculations.

New resin gel for uranium determination by diffusive gradient in thin films technique

A new resin gel based on Spheron-Oxin ® chelating ion-exchanger with anchored 8-hydroxyquinoline functional groups was tested for application in diffusive gradient in thin film technique (DGT) for determination of uranium. Selectivity of uranium uptake from model carbonate loaded solutions of natural water was studied under laboratory conditions and compared with selectivity of the conventional Chelex 100 based resin gel. The affinity of Spheron-Oxin ® functional groups enables determination of the overall uranium concentration in water containing carbonates up to the concentration level of 10 2 mg L −1. The effect of uranium binding to the polyacrylamide (APA) and agarose diffusive gels (AGE) was also studied. Uranium is probably bound in both gels by a weak interaction with traces of acrylic acid groups in the structure of APA gel and with pyruvic and sulfonic acid groups in the AGE gel. These sorption effects can be eliminated to the negligible level by prolonged deployment of DGT probes or by disassembling probes after the 1–2 days post-sampling period that is sufficient for release of uranium from diffusive gel and its sorption in resin gel.

Chelating ion exchange properties of terpolymer resin 2,4-DHPOF-II derived from 2,4-dihydroxypropiophenone

Terpolymer resin 2,4-DHPOF-II was synthesized by the condensation of 2,4-dihydroxy-propiophenone (2,4-DHP) and oxamide (O) with formaldehyde (F) in the presence of 2M HCl as catalyst at 126 ± 1°C. Terpolymer was characterized by UV-visible, IR, 1H NMR spectral and thermal analysis. It is proved to be a selective chelating ion exchange terpolymer for Fe+3,Cu+2, Hg+2,Ni+2,Co+2,Zn+2,Cd+2 and Pb+2 metal ions. Chelating ion-exchange properties of synthesized terpolymer were studied for above mentioned metal ions. A batch equilibrium method was employed to study the selectivity of metal ion's uptake involving the measurements of distribution of given metal ion between sample and solution. Study was carried out using different parameters like pH range, shaking time and media of various ionic strengths.

Thermal and ion-exchange studies on chelating terpolymer resins derived from o cresol urea formaldehyde

Terpolymers prepared by condensation of o cresol and urea with formaldehyde in presence of acid catalyst (2M HCl) proved to be selective chelating ion exchange resins for certain metal ions. The molecular weights of the synthesised terpolymers were determined by GPC Technique. TGA analysis was employed to study the thermal stability and the kinetic data like activation energy of the terpolymer resins. Chelation ion exchange properties of these terpolymers were studied for Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+ and Cd2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal ion uptake involving the measurements of distribution of a given metal ion between the polymer samples. The study was carried out over a wide pH range and in media of various ionic strengths.

Adsorption kinetic character of copper ions onto a modified chitosan transparent thin membrane from aqueous solution

A modified chitosan transparent thin membrane (MCTTM) was prepared and used as the adsorbent to investigate the adsorption kinetics due to excellent capacity of removing copper ions in water solution. The structure and morphology of MCTTM were characterized by SEM analysis and FTIR analysis. External mass transfer, intra particle diffusion, and pseudo-first and pseudo-second order models were used to describe the adsorption process. The results obtained from the study illustrated that the adsorption process could be described by the pseudo-second order model, which indicated adsorption process was a chemical adsorption behavior of chelation ion exchange proved by the FTIR and adsorption free energy analysis. External mass transfer and intra particle diffusion processes were the rate-controlling steps.

Removal of Cd(II) and Pb(II) complexes with glycolic acid from aqueous solutions on different ion exchangers

The sorption of Cd(II) and Pb(II) ions from aqueous solutions on different ion exchangers was investigated by using glycolic acid (GA) as a complexing agent. Glycolic acid is useful for organic synthesis in oxidation–reduction, esterification, and long-chain polymerization. The experiments were carried out by using the following chelating ion exchangers: Purolite S-930, Purolite S-940, Purolite S-950, Diaion CR-20, and Wofatit MC-50 and the cationic ion exchangers: Purolite C-104, Lewatit CNP-80, and Lewatit SP-112. The influence of the initial concentration of Cd(II) and Pb(II) and glycolic acid, pH of the solution, and phase contact time on the sorption percentage was determined in the batch experiments. Pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data, and the rate constants were evaluated. The experimental data, fitted using the Langmuir and Freundlich adsorption models, were applied to describe the equilibrium isotherms and determined the isotherm constants. The Cd(II) and Pb(II) concentrations in the raffinate were determined by the AAS method.

Synthesis of resin IV: Salicylic acid, diaminonaphthalein, and formaldehyde terpolymer and its ion exchange

AbstractThis 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

Diphonix Resin ® in sorption of heavy metal ions in the presence of the biodegradable complexing agents of a new generation

This paper presents the equilibrium and kinetic studies of Cu(II), Zn(II), Co(II), Pb(II) and Cd(II) complexes with Dissolvine GL-38 (GLDA) and Enviomet™ C140 (EDDS) from aqueous solution by the chelating ion exchanger Diphonix Resin ®. The selected complexing agents Dissolvine GL-38–tetrasodium salt of N,N-bis(carboxylmethyl)- l-glutamic acid and Enviomet™ C140–trisodium salt of ethylenediaminedisuccinic acid belong to the group of a new generation of complexons which easily undergo biodegradation but their complexes are not biodegradable. The effect of pH, phase contact time and concentration has been studied using the batch technique at room temperature. After achieving the best conditions for complexes sorption, isotherms were obtained and fitted to the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) models. The kinetic data were fitted using the pseudo-first-order, pseudo-second-order and intraparticle diffusion models. The respective characteristic rate constants were presented. The results showed that the sorption processes of Cu(II), Zn(II), Co(II), Pb(II) and Cd(II) complexes with Dissolvine GL-38 and Enviomet™ C140 on Diphonix Resin ® followed well the pseudo-second-order kinetics.

Lead-sensitive membrane electrode based on chelating ion exchanger

A new selective membrane electrode for the measurement of lead activities is proposed. The preparation of active components of the membrane is described. The ready made electrode insert was used in which the PVC membrane was replaced by the prepared membrane. Experimental results document the emf response of profile, the selectivity, the detection limit and the effect of the sample media. The prepared electrode was applied for the measurement of the lead concentration in water samples. Activated alumina micro-column was used for the pre-concentration of lead in the analyzed water samples. The obtained results were compared with those determined by atomic absorption spectrometry.

Expression and purification of avian influenza virus H5N1 NP protein, and screening interaction proteins of host cells in vitro

To express and purify H5N1 influenza virus (A/Anhui/1/2005) NP in prokaryotic system and to explore the NP-interacting proteins of human bronchial epithelial cells BEAS-2B in vitro. The full length H5N1 NP gene fragment was amplified by PCR, inserted into prokaryotic expression vector (pET30a) to generate NP expression plasmid pET30a-NP. After transforming pET30a-NP into E. coli (BL21), the expression of soluble NP protein was induced by IPTG. The expressed NP protein was purified by two steps with metal chelation chromatography and ion exchange chromatography. Then the total proteins of BEAS-2B cells was extracted for screening the components which have protein-protein interaction with purified NP by pull-down and LC-MS/MS methods. The expression of H5N1 NP protein could be induced by IPTG in bacterial system using expression plasmid pET30a-NP. The soluble NP was purified. Twenty proteins were found by pull-down and LC-MS/MS, the further experiments may be needed to prove protein-protein interaction between them. The soluble H5N1 NP fusion protein with high purity was obtained and twenty proteins were found which could interact with it by pull-down and LC-MS/MS.

Selective Adsorption of Palladium(II) Complexes onto the Chelating Ion Exchange Resin Dowex M 4195 – Kinetic Studies

The chelating ion exchange resin – Dowex M 4195 was used in palladium(II) complexes adsorption from the acidic solutions. This study discusses the sorption kinetics, and more specifically the interparticle diffusion behavior of palladium(II) onto Dowex M 4195. The adsorption studies were used to determine the amount of palladium(II) complexes uptake (resin loading), the distribution coefficients, and the recovery efficiency of Pd(II) complexes. The influence of the agitation speed, the beads size (mean radius of swollen particles), the palladium concentrations, as well as acid concentrations (ionic strength of solutions), the macrocomponent addition (sodium chloride), and the phases contact time was also discussed. Moreover, the effect of temperature was taken into account during the determination of the isotherms. The experimental data obtained at 100 µg/cm3 Pd(II) initial concentration were applied to the kinetic models, and the sorption parameters as well as the normal standard deviation were calculated. Moreover, the Langmuir, Freundlich, and Tempkin‐Pyzhev isotherm models were applied and the isotherms parameters were calculated.