Selective separation and concentration of Pd(II) from Fe(III), Co(II), Ni(II), and Cu(II) ions using thiourea‐formaldehyde resin

Thiourea‐formaldehyde (TUF), a well‐known chelating resin, has been synthesized and it was used in the adsorption, selective separation, and concentration of Pd(II) ions from Fe(III), Co(II) Ni(II), and Cu(II) base metal ions. The composition of the synthesized resin was determined by elemental analysis. The effect of initial acidity/pH and the adsorption capacity for Pd(II) ions were studied by batch technique. The adsorption and separation of Pd(II) were then examined by column technique. FTIR spectra and SEM/EDS analysis were also recorded before and after the adsorption of Pd(II). The optimum pH was found to be 4 for the adsorption. The adsorption data fitted well to the Langmuir isotherm. The maximum adsorption capacity of the TUF resin for Pd(II) ions was found to be 31.85 mg g⁻¹ (0.300 mmol g⁻¹). Chelating mechanism was effective in the adsorption. Pd(II) ions could be separated efficiently from Fe(III), Cu(II), Ni(II), and Co(II) ions using TUF resin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effect of composition and ageing of chloride solutions on extraction of Rh(III) and Ru(III) with phosphonium ionic liquids Cyphos IL 101 and IL 104

ABSTRACT

Rhodium(III) and ruthenium(III) were extracted from chloride solutions with phosphonium ionic liquids trihexyl(tetradecyl)phosphonium chloride or trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate in toluene. Influence of HCl and NaCl presence in the feed and IL concentration in the organic phase were determined. Rh(III) transport appeared to be inefficient, while over 70% of Ru(III) was extracted from 3 M HCl. Ru(III) extraction was affected by the feed acidity and the type of extractant used. The spectra of the extracts indicated some changes in the structure of Rh(III) and Ru(III) complexes in the organic phase. Also, ageing of feed solutions on the extraction of Ru(III) and Rh(III) was studied.     

Adsorption of copper(II), cobalt(II), and iron(III) ions from aqueous solutions on poly(ethylene terephthalate) fibers

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     

Piperazine Functionalized Resins for Au(III), Pt(IV), and Pd(II) Sorption

The result of synthesis of anion exchangers bearing piperazine functionalities is presented in this paper. A series of new ion exchange resins was synthesized by modification of VBC/DVB copolymer with 1(2-aminoethyl)piperazine (resin 1P), 1-amino-4-methylpiperazine (resin 2P), and 1-methylpiperazine (resin 3P). Adsorption studies of gold, platinum, and palladium were conducted with batch and dynamic method from multicomponent solutions containing AuCl₄^?, PtCl₆^2?, and PdCl₄^2? in the concentration range 10 mg/dm³ to 919 mg/dm³. The resins revealed excellent sorption ability towards these metals. The greatest total sorption capacities were determined as 331 mg/g Au for 2P resin, 405 mg/g Pt for 3P resin, and 150 mg/g Pd for 1P resin. The examined 3P resin showed the best total sorption capacity 796 mg/g. Affinity studies were also conducted. The examined resin 1P revealed the greatest affinity to platinum and palladium (lgK 4.5-5) whereas resin 2P revealed the best affinity to gold where lgK were ca. 4.9.     

Rapid and Selective Adsorption of Rh(III) from its Solutions Using Cellulose-Based Biosorbent Containing Iminodiacetate Functionality

A new chelating biosorbent with iminodiacetate functionality was prepared. This biosorbent showed a powerful uptake behavior towards Rh(III) from its dilute solutions. The kinetic and thermodynamic characteristics of the uptake process were evaluated using the batch method. The recovery percentage value obtained is comparable to that of a commercial one with the same functionality (Chelest IRY) but with faster kinetics. Fast and selective adsorption of Rh(III) from Pd (II) and Pt(IV) during column experiments makes the resin promising in the field of Rh(III) recovery from the spent catalytic convertors. The adsorbed rhodium was recovered simply by burning the spent resin.     

Crossflow filtration of iron(III), copper(II), and cadmium(II) aqueous solutions with alginic acid/cellulose composite membranes

The removal of Fe(III), Cu(II), and Cd(II) ions from aqueous solutions was investigated with a crossflow filtration technique. Alginic acid (AA)/cellulose composite membranes were used for retention. In the filtration of Fe(III) solutions, the effects of the crossflow velocity, applied pressure, AA content of the membranes, and pH on the retention percentage and the permeate flux were examined. The maximum retention percentage was found to be 89% for a 1 × 10^?4M Fe(III) solution at the flow velocity of 100 mL/min and the pressure of 60 kPa with 0.50% (w/v) AA/cellulose composite membranes at pH 3. Aqueous solutions of Cu(II) and Cd(II) were filtered at the flow velocity of 100 mL/min and pressure of 10 kPa. The effects of the AA content of the membranes and pH of the waste medium on the retention percentage and the permeate flux were determined. For 1 × 10^?4M Cu(II) and Cd(II) solutions, the maximum retention percentages were found to be 94 and 75%, respectively, at pH 7 with 0.50% (w/v) AA/cellulose composite membranes. When metal‐ion mixtures were used, the retention percentages of Fe(III), Cu(II), and Cd(II) were found to be 89, 48, and 10%, respectively, at pH 3 with 0.50% (w/v) AA/cellulose composite membranes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Extraction and separation of HCl and Rh(III) with trioctylamine

In this paper the use of trioctylamine (TOA) to extract HCl from Rh(III)-containing solutions generated by a supported liquid membrane (SLM) process is investigated. TOA was found to extract HCl readily (in a single contact of 3 min duration) at a molar ratio [HCl]/[TOA] equal to one. For each mole of HCl extracted an equivalent amount of H₂O was found to be extracted as well. As far as Rh(III) extraction of TOA is concerned this was found to depend on the age of the solution and the Cl⁻ concentration. Prolonged aging (accelerated by heating) or [Cl⁻]⩾3 M was found to completely suppress the extraction of Rh(III) by TOA. The chloride ion concentration effect was attrib-uted to Le Chatelier's principle while the aging effect was attributed to the aquation/conversion of the extractable RhCl₆³⁻ complexes to RhCl₅(H₂O)²⁻. The aquation reaction was studied with UV–Visible spectroscopy in an effort to substantiate the solvent extraction (SX) results. On the basis of the findings of this work a combined SLM/SX process flowsheet is proposed according to which the Rh(III) and HCl co-transported through the supported liquid membrane are co-extracted by TOA and subsequently separated by differential stripping; Rh(III) with 0·5 M HCl/3 M Cl⁻ medium and HCl with NAOH.     

Separation of gold(III) ions from copper(II) and zinc(II) ions using thiourea–formaldehyde or urea–formaldehyde chelating resins

Thiourea–formaldehyde (TF) and urea–formaldehyde (UF) chelating resins were synthesized and these resins were used in the separation of gold(III) ions from copper(II) and zinc(II) base metal ions. In the experimental studies, the effect of acidity on gold(III) uptake and gold(III) adsorption capacities by batch method, and loading and elution profiles of gold(III) ions, gold(III), copper(II), and zinc(II), dynamic adsorption capacities and the stability tests of TF and UF resins by column method were examined. By batch method, the optimum acidities were found as pH 2 and 0.5M HCl, and gold(III) adsorption capacities in the solutions including copper(II) and zinc(II) ions were obtained as 0.088 and 0.151 meq Au(III)/g for UF and TF resins, respectively. On the other hand, by column method, the dynamic adsorption capacities were calculated as 0.109 meq Au(III)/g with TF, 0.023 meq Au(III)/g with UF, 0.015 meq Cu(II)/g with TF, 0.0057 meq Cu(II)/g with UF, and under 6.1 × 10^?5 meq Zn(II)/g with TF or UF. TF resin was more effective in the separation and the concentration of gold(III) ions from copper(II) and zinc(II) ions than UF resin. It was seen that sulfur atoms contributed the gold(III) adsorption comparing with oxygen atoms. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Separation and concentration processes of solutions of Co(II), Ni(II), Cr(III), Fe(III) and Mn(II) by extraction with toluene-dissolved rosin

The extraction and stripping of Co(II), Ni(II), Cr(III) and Fe(III) from aqueous solutions by rosin dissolved in toluene has been investigated. Results obtained show that rosin is better extractant than abietic or n-lauric acids under comparable conditions. From these results, and the data of Mn(II) solvent extraction studied previously under the same conditions, a separation and concentration process for these five cations in aqueous solutions has been designed. Saturated solutions of Fe(III), Cr(III), Mn(II) and finally Co(II) and Ni(II) have been obtained successively by extraction and stripping, by addition of ammonium hydroxide to obtain the appropriate pH value, and by modifying adequately the organic phase/aqueous phase volume ratio.     

Separation of gibberellic acid (GA3) by macroporous adsorption resins

The adsorption effects of several macroporous adsorption resins for gibberellic acid (GA3) were investigated. The dynamic adsorption capacity is 58.38 mg/g dry beads for resin R4 and 96.46 mg/g dry beads for resin R5 which is consistent with the surface area. Aqueous methanol (50%, V/V) is a good eluent and the yield of GA3 is above 95%. The concentration of GA3 could increase five-fold after an adsorption-elution cycle and this is important when considering further crystallization of GA3 in an industrial process. __________ Translated from Ion Exchange and Adsorption, 2007, 23(3): 252–258 [译自: 离子交换与吸附]     

Separation of gibberellic acid (GA3) by macroporous adsorption resins

Adsorption rates of gibberellic acid (GA3) on S‐8 and X‐5 resins were measured with the results indicating that the adsorption attained equilibrium for adsorption times longer than 4 h. The adsorption isotherms of GA3 on AB‐8, X‐5, S‐8, D4020, D3520, D4006 and NKA‐9 were determined at 20 °C. S‐8 resin had the largest solid/liquid distribution coefficient of 10.5 and was selected as the adsorbent for separation of GA3 from the aqueous solution. The breakthrough curves of GA3 from the aqueous solution on S‐8 resin were determined at different flow rates. The dynamic adsorption capacity of GA3 was measured as 4.56 mgg⁻¹ wet resin at a flow rate of 0.5 cm³min⁻¹. GA3 adsorbed on S‐8 resin was eluted with several eluents with 80% (v%) acetone aqueous solution having the best desorption performance. When GA3 was adsorbed by S‐8 resin from the fermentation liquor, the dynamic adsorption capacity of GA3 was increased to 12.02 mgg⁻¹ wet resin in virtue of the salting‐out effect of the ammonium sulfate in the fermentation liquor. The yield of GA3 was above 90% after GA3 was adsorbed by S‐8 resin from the fermentation liquor at pH 2 and eluted by 80% (v%) acetone aqueous solution. The GA3 concentration was increased seven‐fold from the fermentation liquor after an adsorption and desorption cycle. © 2000 Society of Chemical Industry     

生物吸附-磁分离法处理含Pd(II)/Al(III)的废液

为了探索处理含Pd2+和Al3+废液的新工艺,以趋磁细菌(MTB)作为生物吸附剂进行了吸附及分离实验研究。结果表明,MTB对Pd2+和Al3+具有很好的吸附效果,并且在Pd-Al二元体系中对Pd2+具有独特的优先吸附性。MTB对Pd2+和Al3+的吸附等温线和吸附动力学曲线分别遵循Langmuir吸附模型和拟二阶动力学模型。磁分离实验结果表明,随着磁场强度的增加,分离效果提高的同时,分离速率也显著提高。经生物吸附-磁分离法复合工艺处理后的出水中Pd2+和Al3+的质量浓度分别为0.014 mg/L和0.213 mg/L。     

Removal of Cu(II), Fe(III), and Cr(III) from Aqueous Solution by Aniline Grafted Silica Gel

Abstract

The aniline moiety was covalently grafted onto silica gel surface. The modified silica gel with aniline groups (SiAn) was used for removal of Cu(II), Fe(III), and Cr(III) ions from aqueous solution and industrial effluents using a batch adsorption procedure. The maximum adsorption of the transition metal ions took place at pH 4.5. The adsorption kinetics for all the adsorbates fitted better the pseudo second‐order kinetic model, obtaining the following adsorption rate constants (k₂): 1.233 · 10^?2, 1.902 · 10^?2, and 8.320 · 10^?3 g · mg^?1 min^?1 for Cr(III), Cu(II), and Fe(III), respectively. The adsorption of these transition metal ions were fitted to Langmuir, Freundlich, Sips, and Redlich‐Peterson isotherm models; however, the best isotherm model fitting which presented a lower difference of the q (amount adsorbed per gram of adsorbent) calculated by the model from the experimentally measured, was achieved by using the Sips model for all adsorbates chosen. The SiAn adsorbent was also employed for the removal of the transition metal ions Cr(III) (95%), Cu(II) (95%), and Fe(III) (94%) from industrial effluents, using the batch adsorption procedure.     

Adsorption of Cu(II) ions from aqueous solutions using ion exchange resins with different functional groups

The extraction of heavy metals from industrial effluents using efficient adsorbents is crucial for wastewater treatment and beneficial for metal recycling. In this study, the removal of Cu(II) from an acidic solution by commercial resins Dowex G-26 and Puromet™ MTS9570 was investigated. The influences of contact time, solution concentration, pH, temperature, and a resin dosage on the adsorption process were studied with batch technique. The optimum adsorption conditions were obtained at a concentration of 1100 mg/L Cu, contact time of 30 min, pH 3.5, and resin dosage of 0.025 g/ml for the removal of 99.9% and 90% of copper ions by G-26 and MTS9570, respectively. The experimental data of copper adsorption were analyzed using the Langmuir, Freundlich, and Temkin isotherm models. The highest metal uptakes of 41.67 and 37.70 mg/g were observed for Dowex G-26 and MTS9570, respectively. It was found that both resins had higher adsorption capacities than the substances reported in the literature. The adsorption kinetic studies showed that the copper adsorption process could be better described by the pseudo-second order model. Adsorption occurs spontaneously under endothermic conditions, which indicates the endothermic nature of the process.     

Electrochemical behavior of ruthenium (III), rhodium (III) and palladium (II) in 1-butyl-3-methylimidazolium chloride ionic liquid

Electrochemical behavior of ruthenium (III), rhodium (III) and palladium (II) in 1-butyl-3-methylimidazolium chloride (bmimCl) and their ternary and binary solutions in bmimCl was studied at various working electrodes at 373 K by cyclic voltammetry and chronoamperometry. Ruthenium (III) chloride forms a stable solution with bmimCl and the cyclic voltammogram of ruthenium (III) in bmimCl recorded at glassy carbon electrode consisted of several redox waves due to the complex nature of ruthenium to exist in several oxidation states. Electrolysis of ruthenium (III) chloride in bmimCl at the cathodic limit of bmimCl (−1.8 V (vs. Pd)) did not result in ruthenium metal deposition. However, it was deposited from bmimPF₆ and bmimNTf₂ room temperature ionic liquids at −0.8 V (vs. Pd). The electrochemical behavior of ruthenium (III) in bmimCl in the presence of palladium (II) and rhodium (III) was studied by cyclic voltammetry. The presence of palladium (II) in bmimCl favors underpotential deposition of ruthenium metal. The nuclear loop at −0.5 V (vs. Pd) was observed in all solutions when palladium (II) co-existed with other two metal ions. Nucleation and growth of the metal on glassy carbon working electrode was investigated by chronoamperometry. The growth and decay of chronocurrents has been found to follow the instantaneous nucleation model with three-dimensional growth of nuclei.     

Removal of Cu(II), Cr(III), and Cr(VI) from Aqueous Solution using a Novel Agricultural Waste Adsorbent

A novel adsorbent, chufa corm peels (CCP), is used for removing Cu(II), Cr(III), and Cr(VI) from aqueous solutions. The adsorption ability and characteristics of the CCP are thoroughly investigated. The adsorption capability for three heavy metal ions is in the order of Cu(II) > Cr(III) > Cr(VI). The morphology and elemental distribution on the biomass of CCP were evaluated by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Fourier-transform infrared spectroscopy (FTIR) analysis revealed that oxygen-containing functional groups, especially carboxylic and hydroxyl groups were responsible for chemical coordination between ionizable functional groups and metal ions. The adsorption features were evaluated based on the batch biosorption experiment. The results showed that the adsorption well meets the Freundlich adsorption isotherm models and pseudo-second-order kinetics model. In summary, this work demonstrated that CCP is an attractive, efficient, and low-cost adsorbent biomaterial that can be used for the removal of heavy metals from environmental contaminations.     

Adsorption of Cr(III), Ni(II), Zn(II), Co(II) ions onto phenolated wood resin

In this study, phenolated wood resin was used an adsorbent for the removal of Cr(III), Ni(II), Zn(II), Co(II) ions by adsorption from aqueous solution. The adsorption of metal ions from solution was carried at different contact times, concentrations and pHs at room temperature (25°C). For individual metal ion, the amount of metal ions adsorbed per unit weight of phenolated wood resin at equilibrium time increased with increasing concentration and pH. Also, when the amounts of metal ions adsorbed are compared to each other, it was seen that this increase was order of Cr(III) > Ni(II) > Zn(II) > Co(II). This increase was order of Cr(III) > Ni(II) > Co(II) > Zn(II) for commercial phenol–formaldehyde resin. Kinetic studies showed that the adsorption process obeyed the intraparticle diffusion model. It was also determined that adsorption isotherm followed Langmuir and Freundlich models. Adsorption isotherm obtained for commercial phenol–formaldehyde resin was consistent with Freundlich model well. Adsorption capacities from Langmuir isotherm for commercial phenol–formaldehyde resin were higher than those of phenolated wood resin, in the case of individual metal ions. Original adsorption isotherm demonstrated the monolayer coverage of the surface of phenolated wood resin. Adsorption kinetic followed the intraparticle diffusion model. The positive values of ΔG° determined using the equilibrium constants showed that the adsorption was not of spontaneous nature. It was seen that values of distribution coefficient (K_D) decreasing with metal ion concentration in solution at equilibrium (C_e) indicated that the occupation of active surface sites of adsorbent increased with metal ions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2838–2846, 2006     

Separation of Mercury(II) as Chloride from Zinc(II), Cadmium(II), Gold(III), and Thallium(III) by Extraction in High-Molecular-Weight Amines

Abstract

The extraction behavior of Zn(II), Cd(II), Hg(II), Au(III), and Tl(III) has been studied at different HCl molarities in some commercially available liquid anion exchangers. The effect of such variables as the type of amine, molarity of HCl, amine concentration, and organic diluent on extraction has been explored to suggest the best conditions of separation of Hg(II) from Zn(II), Cd(II), Au(III), and Tl(III).