Synthesis of a Dithiocarbamate Chelate Resin and Its Oxidized form and Their Adsorption Properties for Heavy Metal Ions

A series of macroporous dithiocarbamate chelate resins, III and V, and an oxidized resin, VI, with high adsorption capacity were prepared. The influence of various reaction conditions of amination, dithiocarboxylation, and oxidation were examined. The structure and the conversion of functional groups of resins were confirmed by IR spectra and elemental analysis. The adsorption capacities of Resin II for Hg²⁺, Cu²⁺, Zn²⁺, and Cd²⁺ are 4.40, 2.44, 1.77, and 1.36 mmol/g, respectively. The adsorption capacities of Resins V and VI for Cu²⁺. Zn²⁺, Ni²⁺, Co³⁺, Ag⁺, Hg²⁺, Cd²⁺, Pb²⁺, and Au³⁺ are 4.07–0.51 and 3.81–0.59 meq ion/g, respectively. The adsorption rate and the influence of pH on the adsorption percentage of the resins for metal ions were examined. Noble metal, transitional metal, and heavy metal ions can be quantitatively adsorbed by the resins. The adsorbed Cu²⁺, Pb²⁺, Cd²⁺, Co³⁺, and Ni²⁺ can be quantitatively eluted with 5N HNO₃, and the presence of large amounts of Ca²⁺, Mg²⁺, Fe³⁺, and Al³⁺ did not interfere.     

聚乙烯苄多乙烯多胺二硫代羧酸大孔型螯合树脂合成与性质的研究

合成了具有高吸附容量的聚乙烯苄多乙烯多胺二硫代羧酸大孔型螫合树脂(DTC树脂)。探讨了胺化和二硫代羧化中各种反应条件的影响。制得的DTC树脂对Hg~(2+)、Cu~(2+)、Zn~(2+)、Cd~(2+)的吸附容量分别达4.40、2.44、1.77、1.36毫摩尔离子/克,在水中对微量的重金属离子在较宽pH范围内有良好的捕集效果。红外光谱、元素分析证实了合成过程中树脂功能基的转化。     

PREPARATION AND PROPERTIES OF MACRO-POROUS CHELATE RESINS OF CROSSLINKED POLYSTYRENE BEARING DITHIOCARBAMATE GROUPS

The title resins (DTC resins) with high adsorption capacity were prepared. The influences of various reaction conditions of amination and dithiocarboxylation were examined. The adsorption capacities of the produced DTC resin for Hg~(2 ), Cu~(2 ), Zn~(2 ) and Cd~(2 ) are 4.40, 2.44, 1.77 and 1.36 mmol/g, respectively. It is highly effective in collecting traces of heavy metal ions in water over a wide pH range. The conversion of the functional groups were confirmed by the IR-spectra and elementary. analysis.     

STUDY ON THE SYNTHESIS OF POLYSTYRENESUPPORTED MACROCYCLIC MERCAPTAL CHELATING RESIN AND ITS PROPERTIES

Chelating resin with macrocyclic mercaptal group supported on macroporous polystyrene beads was synthesized, which showed good selectivity to Hg~(2+): its complexing capacity amounted to 30—60 mg Hg~(2+)/g resin, two orders of magnitude greater than for other metal ions such as Ca~(2+), Zn~(2+), Cd~(2+), Pb~(2+) etc. This resin could restore the activity of urease which had been deactivated by poisoning with Hg~(2+). Its restoring power was far better than that of the mercapto-resin and common anionic exchange resins. It showed some promising use as an oral polymeric detoxifying drug for mercury poisoning.     

NMR-Spektroskopische Untersuchungen der kinetischen Limitierung der Kationenselektivität eines cadmiumselektiven Ionophors

NMR Studies of the Kinetic Limitation of Cation Selectivity of a Cadmium-Selective Ionophore The Cd²⁺-selective ionophore N,N,N′,N′-tetrabutyl-3, 6-dioxaoctanedithioamide (1) looses its capability to induce cation selectivity in solvent polymeric membranes if these are contacted with Cu²⁺, Pd²⁺, Pt²⁺, Ag⁺ and Hg²⁺. For systems with a free energy of activation of the ligand exchange reaction of more than about 65 kJ mol^?1 (in acetonitrile) the cation complexes of the ionophore act as anion exchangers (Pt²⁺, Pd²⁺). Below about 45 kJ mol^?1 cation permselectivity is observed (Zn²⁺, Cd²⁺). Ag⁺ and Hg²⁺ induce a decomposition of the ionophore.     

Preconcentration and Determination of Copper(II) by Novel Solid-Phase Extraction and High-Resolution Continuum Source Flame Atomic Absorption Spectrometry

Amberlite XAD-4 modified with N-para-anisidine-3,5-di-tert-butylsalicylaldimine was investigated as a new chealting sorbent for the selective separation and preconcentration of Cu(II). The metal ion was retained by chemical sorption on the modified resin, eluted by hydrochloric acid, and determined by high-resolution continuum source flame atomic absorption spectrometry. The prepared resin was characterized for the solid-phase extraction of Cd²⁺, Co²⁺, Cr³⁺, Cu²⁺, Fe³⁺, Mn²⁺, Ni²⁺, Pb²⁺, and Zn²⁺ in a column. The influence of the pH, the mass of solid phase, eluent, flow rate, and sample volume was optimized. Using the optimum conditions, only Cu(II) showed quantitative sorption at the 95% confidence level, and the recoveries of the other metal ions were below 80%. A preconcentration factor 125 was obtained for Cu(II) with a limit of detection of 0.56?µg?L^?1. The method was used for the determination of Cu(II) in tap water, river water, tomato leaves, and fish. The relative standard deviation and the relative error were lower than 7%.     

Quantitative Trennung von Schwermetallen mit Chelataustauschern auf der Basis von Polystyrol

Zusammenfassung Die Trennung und Isolierung von folgenden Schwermetallen bei einem hohen Überschuß an Fremdionen mit Hilfe neuer selektiver Chelataustauscher wird beschrieben: Cu²⁺/Zn²⁺, Cu²⁺/Pb²⁺, Ag⁺/Cu²⁺, Ag⁺/Pb²⁺, Hg²⁺/Zn²⁺, Hg²⁺/Cd²⁺; Abtrennung von Hg²⁺. Unter gleichen Bedingungen war mit dem handelsüblichen Austauscher Dowex A-1 keine Trennung möglich.

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Quantitative separation of heavy metals by means of chelating exchangers based on polystyrol

Summary The separation and isolation of the following heavy metals in presence of a high excess of foreign ions by means of new selective chelating exchangers is described: Cu²⁺/Zn²⁺, Cu²⁺/Pb²⁺, Ag⁺/Cu²⁺, Ag⁺/Pb²⁺, Hg²⁺/Zn²⁺, Hg²⁺/Cd²⁺; separation of Hg²⁺. Under the same conditions no separation could be achieved by the ion-exchanger Dowex A-1.

     

Preconcentration of Metal Ions with Anion-Exchange Resin

A method to preconcentrate metal ions employed an anion-exchange resin was studied. Metal ions were first chelated with ethylenediaminetetraacetic acid (EDTA), then trapped on an enrichment column packed with anion-exchange resin. The major interfering ions, e.g. calcium and magnesium were excluded from enrichment by appropriate adjustment of pH. Desorption of the trapped metals was effected by elution with HCl (0.1 M). Recoveries of Cu²⁺, Ni²⁺, Co²⁺, Pb²⁺, Zn²⁺ reached 99%. By comparison with preconcentration methods using cation-exchange resin, this method has the advantages of selectivity, quantitative recovery, small cost of operation, and simple procedure.     

SYNTHESIS OF MACROPOROUS HUMIC ACID RESINS AND THEIR CHELATING PROPERTIES FOR HEAVY METAL IONS

Macroporous HA resins (HAR) can be prepared in pearl form by grafting HA onto crosslinked PS through azo or through ester and / or ether linkages. At pH 13 and the HA / PSNH_2 weight ratio 0.7—1.0, PSN_2~+-Cl~-couples with HA and results in the formation of a7o-type HA resin (HAR-A), which shows good adsorbility towards heavy metal ions. The Cu~(2+) sorption capacity of ester / ether type humic acid resin (HAR-E) is increased by lengthening the reaction time of HA and PSCH_2Cl. The structure of HAR is discussed on the basis of the IR spectra. The sorption capacity of HAR-A is 1.01 mmol / g for Cd~(2+) and 0.6—0.53 mmol/g for Ni~(2+), Mn~(2+), Cu~(2+), Co~(3+) and Zn~(2+). respectively. The calculated distribution coefficients of heavy metal ions on HAR-A can be arranged in the following order: Cu~(2+)(8.7×10~3)>Cd~(2+) (3.8×10~2)>Zn~(2+)(2.4×10~2)>Ni~(2+)(1.8×10~2)>Mn~(2+)(4.9×10). At pH 6.5, Cu~(2+), Cd~(2+), Ni~(2+), Mn~(2+) can be quantitatively adsorbed by HAR-A and completely eluted with 1N HNO_3. HAR-A can be regenerated and reused. Trace quantities of the above-mentioned heavy metal ions in four samples of the natural occurring water and one sample of the tap water were analyzed by using HAR-A.     

Retention behavior of nickel, copper, cadmium and zinc ions from aqueous solutions on silico-titanate and silico-antimonate used as inorganic ion exchange materials

Silico-titanate (SiTi) and silico-antimonate (SiSb) have been synthesized and characterized using X-ray diffraction patterns, infrared and thermal analysis techniques. Divalent cations such as Ni²⁺, Cd²⁺, Zn²⁺ and Cu²⁺ in the pH range 2 to 8 have been exchanged with the exchangeable active sites of the exchangers using a batch technique. From the results obtained, the equilibrium capacities and distribution coefficient values were calculated indicating high selectivity values for Ni²⁺, Cd²⁺, Zn²⁺ and Cu²⁺ ions on silico-titanate and silico-antimonate compared to other titanates and antimonates. Also SiTi and SiSb show high chemical stability in H₂O, nitric and hydrochloric acids. All these results support the suitability of the prepared materials for the removal of the toxic metals concerned from waste waters. Based on the results obtained, practical separation experiments for the above mentioned cations on SiTi and SiSb columns from aqueous waste solutions were carried out.     

Sorption selectivity of cobalt(II), nickel(II), and copper(II) ions by KB-2E macroreticular carboxylic cation exchanger from aqueous-salt solutions of alkali metals

Sorption selectivity of copper(II), nickel(II), and cobalt(II) ions by KB-2E macroreticular carboxylic cation exchanger in the Na-form from dilute solutions was studied in the target concentration range (0.52.6) 103 M. The equilibrium distribution coefficients of Co²⁺, Ni²⁺, and Cu²⁺ were calculated. The role played by hydration of ions in their sorption by KB-2E cation exchangers is analyzed with consideration for IR spectroscopic, thermal analysis, and scanning electron microscopic data.     

Silver nanoparticle loaded on activated carbon and activated carbon modified with 2-(4-isopropylbenzylideneamino)thiophenol (IPBATP) as new sorbents for trace metal ions enrichment

The efficiencies and performances of silver nanoparticle loaded activated carbon modified with 2-(4-isopropylbenzylideneamino)thiophenol (IPBATP-Ag-NP-AC) and activated carbon modified with IPBATP (IPBATP-AC), as new sorbents, were evaluated for separation and preconcentration of Cu²⁺, Zn²⁺, Co²⁺, Cd²⁺ and Pb²⁺ ions from real environmental samples. The retained metals content was reversibly eluted using 5?mL of CH₃COOH (6.0?mol?L^?1) and/or 10?mL of 4.0?mol?L^?1 HNO₃ for IPBATP-Ag-NP-AC and IPBATP-AC, respectively. The experimental parameters influence the recoveries of metal ions including pH, amounts of ligand and supports, condition of eluents, sample and eluent flow rates of has been investigated. The preconcentration factors were found to be 100 for Zn²⁺, Cd²⁺, Co²⁺, Cu²⁺ and 50 for Pb²⁺ ions using IPBATP-Ag-NP-AC, and 50 for Zn²⁺, Cd²⁺, Co²⁺, Cu²⁺ and 25 for Pb²⁺ ions using IPBATP-AC. The detection limit of both SPE-based sorbents was between 1.6–2.5?ng?mL^?1 for IPBATP-AC and 1.3–2.5?ng?mL^?1 for IPBATP-Ag-NP-AC. The proposed methods have been successfully applied for the extraction and determination of the understudy metal ions content in some real samples with extraction efficiencies higher than 90% and relative standard deviations (RSD) lower than 2.4%.     

Combined Effects of Heavy Metal Ions on Bacteria and the Determination of Heavy Metals by Bioassay

In the framework of the development of bioassay, a procedure was developed for studying the combined effects of heavy metal ions on bacteria. The bacterium Bacillus subtilis niger was proposed as an analytical indicator. A universal calculation system was developed that allows one to obtain and analyze functional models of toxicity and the combined effects of toxicants. Models for the action of Zn²⁺–Cu²⁺, Zn²⁺–Cd²⁺, Zn²⁺–Cu²⁺–Cd²⁺, and Zn²⁺–Cu²⁺–Cd²⁺–Hg²⁺ mixtures on Bacillus subtilis niger were obtained and studied, and are discussed for the first time. The effect of the type of the nutrient medium on the character and structure of the combined effects was studied. The resulting models were applied to the determination of concentrations of heavy metal ions in mixtures.     

Determination of alkali, alkaline earth and transition metal ions in UO2, ThO2 powders and sintered (Th,U)O2 pellets by ion chromatography

An ion chromatographic method has been developed for the determination of traces of Li⁺, Na⁺, K⁺, Ca²⁺, Mg²⁺, Sr²⁺, Fe³⁺, Cu²⁺, Ni^2+, Co²⁺, Zn²⁺, Cd²⁺, Mn²⁺ in UO₂, ThO₂ powders and sintered (Th,U)O₂ pellets. This new method utilizes poly-(butadiene-maleic acid) (PBDMA) coated silica cation exchange column and mixed functionality column of anion and cation exchange to achieve the separation of alkali, alkaline earths and transition metal ions, respectively. It involves matrix separation after sample dissolution by solvent extraction with TBP (tri butyl phosphate)-TOPO (tri octyl phosphine oxide)/CCl₄. Interference of transition metal ions in the determination of alkali, alkaline earth metal ions are removed by using pyridine 2,6-dicarboxylic acid (PDCA) in the tartaric acid mobile phase. Mobile phase composition is optimized for the base line separation of alkali, alkaline earth and transition metal ions. Linear calibration graphs in the range 0.01–20 μg mL⁻¹ were obtained with regression coefficients better than 0.999. The respective relative standard deviations were also determined. Recoveries of the spiked samples are within ±10% of the expected value. The developed method is authenticated by comparison with certified standards of UO₂ and ThO₂ powders.     

L‐lysine and EDTA polymer mimics as resins for the quantitative and reversible removal of heavy metal ion water pollutants

Traditional precipitation methods for inorganic micropollutant removal from waters are increasingly being replaced by sorption methods based on both natural and synthetic materials. In this context, two novel effective heavy metal ions absorbers are presented. These resins, LYMA and LMT85, were crosslinked poly(amidoamine)s carrying amine and carboxyl groups in their repeating units. In particular, the LYMA‐repeating unit contains one carboxyl and two amine groups and is a mimic of L ‐lysine, whereas LMT85 contains two amine and five carboxyl groups and is a mimic of EDTA. Both resins were prepared at moderate cost by simple eco‐friendly procedures. The heavy metal ion set adopted as benchmark was Cu²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Ni²⁺, and Co²⁺. LYMA proved selective for Cu²⁺ and Ni²⁺, the other ions tested being negligibly absorbed, whereas LMT85 proved capable of rapidly and quantitatively absorbing all the ions tested either singly or in mixed solution. The absorption process was reversible, and the resins were easily regenerated by acidification. The absorption of several metal ions imparted intense coloring to the resins, a feature possibly exploitable for analytical purposes. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

On-line trace metal enrichment and matrix isolation in atomic absorption spectrometry by a column containing immobilized 8-quinolinol in a flow-injection system

Metal ions (Cu²⁺, Co²⁺, Cd²⁺, Ni²⁺, Pb²⁺, Zn²⁺) were concentrated quantitatively and isolated from the sample matrix by a colum     

A chelating resin with bis[2-(2-benzothiazolylthioethyl)sulfoxide]: Synthesis, characterization and properties for the removal of trace heavy metal ion in water samples

A new chelating resin containing bis[2-(2-benzothiazolylthioethyl)sulfoxide] was synthesized using chloromethylated polystyrene as material and characterized by elemental analysis and infrared spectra. The adsorption capacities of the newly formed resin for Hg²⁺, Ag⁺, Cu²⁺, Zn²⁺, Pb²⁺, Mn²⁺, Ni²⁺, Cd²⁺ and Fe³⁺ were investigated over the pH range 1.0-6.0. The resin exhibited no affinity for alkali or alkaline earth metal ions. The maximum adsorption capacities of the resin for Hg²⁺, Ag⁺, Cu²⁺, Zn²⁺, Pb²⁺, Mn²⁺, Ni²⁺, Cd²⁺ and Fe³⁺ were 1.49, 0.96, 0.58, 0.11, 0.37, 0, 0.24, 0.36 and 0.25 mmol g⁻¹, respectively. In column operation it had been observed that Hg²⁺ and Ag⁺ in trace quantity could be separated from different binary mixtures and Hg²⁺ could be effectively removed from industrial wastewater and the natural water spiked with Hg²⁺ at usual pH.     

Studies on Synthetic Inorganic Ion Exchangers-III Quantitative Separations of Mg2+ -Pb2+, Zn2+ - Pb2+ Cu2+ - Pb2+, Al3+ - Pb2+, Zn2+ - Cd2+, and Mg2+ - Cd2+ on Lead Antimonate Columns

Abstract

A new inorganic ion exchanger, lead antimonate has been synthesized having an Pb:Sb ratio of 1:5 and cation exchange capacity of 1.46 mequiv./g. It is fairly stable in water and dilute solutions of acids, bases and salts. Ion distribution studies on twenty metal ions have been determined on this gel at pH 1,2,3 and 5. The following mixtures have been separated: Mg²⁺ - Pb²⁺, Zn²⁺ - Pb²⁺, Zn²⁺ - Pb²⁺, Cu²⁺ - Pb²⁺, Al³⁺ - Pb²⁺, Zn²⁺ - Cd²⁺ and Mg²⁺ - Cd²⁺. Mg²⁺ and Al³⁺ were removed with 0.4 M ammonium nitrate, Cu²⁺ and Zn²⁺ with 0.4 M ammonium nitrate + 0.1M nitric acid (1:1), Pb²⁺ with 0.5M nitric acid and Cd²⁺ with 0.25M nitric acid. A tentative structure of this material is proposed on the basis of chemical analysis, pH titrations, thermogravimetry and IR spectrophotometry.     

Synthesis of Functional Resins Containing Heterocyclic Rings and Their Sorption Properties for Noble-Metal Ions

Five kinds of functional resins, 2-aminopyridine resin (2-APR), 3-APR, 4-APR, 2-hydroxypyridine resin (2-HPR), and 2-thiolbenzothiazole resin (2-TBTR), were synthesized. The functional group capacities of the resins were 3.0–4.2 mmol/g resin. The sorption capacities of 4-APR, 3-APR, and 2-APR for Au(III) and Pt(IV) were 3.12–3.22 mmol Au(III)/g APR and 1.27–1.60 mmol Pt(IV)/g APR. The molar complex ratios, Au(III)/NH-C₅H₄N and Pt(IV)/NH-Cs H₄N were 0.84–0.97 and 0.34–0.48, respectively. Selective sorption of 4-APR for various coexistent metal ions over a wide acidity range (1–5 N HCl) was in the following order: Pt(IV) > Au(III) > Cd²⁺ > Zn²⁺ > Pd(II) > Mn²⁺, Cu²⁺, Fe³⁺. The Au(III) adsorbed on APR can be quantitatively eluted with 2% aqueous thiourea. The regenerated APR can be reused without apparent decrease in the sorption capacity for Au(III). The separation of Au(III) and Cu²⁺ was studied preliminarily. The excellent properties show that APR may be used in the gold industry. The sorption capacities of 2-HPR for Au(III) is 0.99 mmol Au(III)/g 2-HPR. That of 2-TBTR for Au(III) is less than that of APR. 2-HPR is stable below 100°C, while 4-APR and 2-APR are stable below 80°C in air.     

Synthetic functionalized terpolymeric resin for the removal of hazardous metal ions: synthesis,characterization and batch separation analysis

An effectual functionalized synthetic resin involving anthranilic acid/4‐nitroaniline/formaldehyde was synthesized for the detoxification of hazardous metal ions. The resin was characterized by Fourier transform infrared, ¹H, and ¹³C nuclear magnetic resonance spectroscopy, and its morphology was established through scanning electron microscope and X‐ray diffraction. The resin was analyzed by thermogravimetric analysis to assess the thermal stability, in which the resin could be used in high temperature aqueous solutions for the elimination of harmful metal ions. The ion‐exchange property of the resin was evaluated by batch technique for specific metal ions viz. Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, and Pb²⁺. The study was extended to three variations such as effect of metal ion uptake in the presence of various electrolytes in different concentrations, effect of pH, and effect of contact time. The outcome proved that the resin can be used as a strong cation‐exchanger to remove various metal ions from the solutions. The resin could be regenerated and reused with quantitative recovery of metal ions for few cycles. On comparison with the earlier reported resins, the synthesized resin has found excellent capability of metal ion recovery. The resin possesses an utmost ion‐exchange capacity, which is in good harmony with isotherm models and kinetics. Copyright © 2015 John Wiley & Sons, Ltd.