Purolite S950 Research Articles

Adsorption ability of chelating resin Purolite S930 for removal of metal complex azo dye from aqueous solutions

Adsorption ability of chelating resin Purolite S930 for removal of metal complex azo dye from aqueous solutions

Sorption rerecovery and concentration of rare-earth metals from extraction phosphoric acid. Review

The review covers the methods for sorption recovery and concentration of rare-earth metals (REM) from solutions of extraction phosphoric acid (EPA). Sorption extraction of the REM seems most appropriate at the stage of primary concentration, but a significant amount of iron (III) and calcium as the most interfering impurities are the problem, both at the stage of sorption and at the stage of desorption. The results of studies on the sorption of trivalent ions of cerium, lanthanum and iron on sulfonic cation-exchange resin KU-2-8 and macroporous weakly acidic cation exchange Cybber CRX 300, are presented. It is established that the cation exchanger Cybber CRX 300 by exchange capacity for lanthanum and cerium and kinetic properties is inferior somewhat to sulfonic cation-exchange resin KU-2-8 at sorption from acidic solutions, but can be used to concentrate and separate the REM from iron. The review presents data of the pilot trials of the technology for extracting rare-earth metals from dihydrate extraction phosphoric acid (45 % P2O5) produced by «PhosAgro-Cherepovets» JSC (RU). The results of tests of sorbents TP260, Purolite S957 (Monophos), sulfonic cation-exchange resin РРС 160 and sorbent АА03 at sorption: from sulphate solution after decomposition of phosphate raw materials; from a solution of hydrolysis sulfuric acid after precipitation of titanium dioxide; from sulfuric acid solutions after sorption of uranium are presented. The distribution of rare-earth metals during their sorption by KU-2 sulfonic cation-exchange resin from solutions of phosphoric acid, as follows: dihydrate EPA partially evaporated 43.69 wt. % P2O5, «Balakovo Mineral Fertilizers» JSC; dihydrate EPA, without evaporation 26.09 wt. % P2O5, OJSC «Ammofos»; dihydrate EPA, evaporated 52.54 wt. % P2O5, «Ammofos» OJSC, was studied. The distribution coefficients of individual lanthanides are obtained. The analysis of literature data has shown that the choice of sorbent is the most difficult task when developing the technology for sorption extraction of REM from multicomponent solutions.

Batch adsorption study of uranium on various ion exchange resins as an alternative method to solvent extraction

The project is aimed at recovering uranium from scrap material containing useful amounts of Low Enriched Uranium. The common method of recovering uranium is by using acidic or alkaline medium for dissolution, followed by solvent extraction using tributyl phosphate in kerosene. However the normal challenge with solvent extraction is the generation of enormous liquid waste which is slightly radioactive. Therefore in this project we studied the adsorption of uranium on various ion exchange resins in order to use it as an alternative method to solvent extraction. Uranium solution from the scrap materials was used, and different ion exchange resins such as Amberjet 1600 H, PPC100H, Purolite S940 and S950 chelation resin, and Purolite A500 were tested under various conditions for the adsorption of uranium. The strong acid cation resins show no selectivity between the uranium and aluminium species, both species were fully adsorbed irrespective of the pH. The strong base anion resins had good uranium adsorption attaining 100%, they also show a pH effect for the aluminium adsorption. The use of ion exchange resins, especially with anion resins showed promising results and potential for use as an alternative to solvent extraction.

Selective Extraction of Rare Earth Elements from Phosphoric Acid by Ion Exchange Resins

Rare earth elements (REE) are present at low concentrations (hundreds of ppm) in phosphoric acid solutions produced by the leaching of phosphate ores by sulfuric acid. The strongly acidic and complexing nature of this medium, as well as the presence of metallic impurities (including iron and uranium), require the development of a particularly cost effective process for the selective recovery of REE. Compared to the classical but costly solvent extraction, liquid-solid extraction using commercial chelating ion exchange resins could be an interesting alternative. Among the different resins tested in this paper (Tulsion CH-93, Purolite S940, Amberlite IRC-747, Lewatit TP-260, Lewatit VP OC 1026, Monophos, Diphonix,) the aminophosphonic IRC-747, and aminomethylphosphonic TP-260 are the most promising. Both of them present similar performances in terms of maximum sorption capacity estimated to be 1.8 meq/g dry resin and in adsorption kinetics, which appears to be best explained by a moving boundary model controlled by particle diffusion.

The effect of contaminants on the application of polyamine functionalised ion exchange resins for uranium extraction from sulfate based mining process waters

Three in-house produced polyamine functionalised ion exchange resins and Purolite S985 (a commercial ion exchange resin) have been assessed for their ability to extract UO22+ from a variety of aqueous matrices applicable to current and potential future uranium mining processes. The uptake of common contaminant species in uranium processing liquors at variable acid concentrations has been assessed, with Al3+ and MoO42− showing the most extraction, with AsO43−, Eu3+ and Fe3+ showing extractions >10% at low [H+]. Extraction of MoO42−, AsO43−, Eu3+ and Fe3+ was seen to decrease with increasing [H+]. The impact of increasing [Cl−] on UO22+ and Fe3+ extraction has been determined. Fe3+ showed low extractions by all resins, with no dependence on [Cl−]. In contrast, increasing suppression of UO22+ uptake was seen with increasing [Cl−] up to 80 g L−1, with extraction remaining constant beyond this [Cl−]. At high [Cl−] (>50 g L−1) Purolite S985 was seen to remove UO22+ from solution more effectively than all synthesised polyamine resins. The presence of Fe3+ in solution was seen to suppress UO22+ uptake by around 10% when [Fe3+]/[UO22+] increased from 0 to 2. Fe3+ extraction by all studied resins was promoted by the presence of UO22+ in solution. This was most prevalent with Purolite S985, with an extraction of 30% for [Fe3+]/[UO22+] = 2 by Purolite S985. All resins were tested using a process water from a uranium mine and have shown an ability to selectively extract UO22+ from such solutions, with the best synthetic resin recovering 15.7% more uranium than Purolite S985.

Separation of cations of heavy metalsfrom concentrated galvanic drains

When applying galvanic coatings, soluble salts of heavy metals such as iron, copper, nickel, zinc, cadmium, chromium and other metals are used, toxic cations enter the water, with subsequent migration to the biosphere. To date, many methods have been developed for cleaning galvanic sewage, which cannot be considered sufficiently effective. The joint sorption of divalent cations of copper, nickel and cadmium from concentrated aqueous solutions was investigated. Calculation and experimental methods were used to determine the separation conditions of the bivalent ion systems that differed and close in sorption properties on the aminophosphonic polyampholyte Purolite S950 in a natrium form. It is shown that the cadmium (II) cations can be isolated from solutions containing copper (II) or nickel (II) cations even at the height of the sorption layer of 0.13 m due to the difference in the defining characteristics of the cations. This layer height can be used not only in a chromatographic column, but also in a concentrating cartridge. Separation of the copper (II) and nickel (II) close to the sorption properties requires an absorbing layer of 0.76 m, which can only be used in a chromatographic column, but not for a concentrating cartridge. In this paper, the degrees of ion separation in various sorption conditions are calculated. The applicability of the conductometric method for controlling the ion exchange process is shown not only when the free cations are isolated from aqueous solutions but also bound to complexes.

Extraction of uranium from non-saline and hypersaline conditions using iminodiacetic acid chelating resin Purolite S930+

Uptake behaviour of uranium from aqueous, acidic sulfate and chloride media on iminodiacetic acid chelating resin Purolite S930+ has been studied. Experiments have followed UO22+, Cu2+ and Fe3+ uptake behaviour with respect to acidic and ionic media type and concentration. Uptake suppression of all metals was observed at [H+] > 0.1 M sourced from H2SO4 and HCl. In contrast, significant uptake of Fe3+ was observed from solutions with [HCl] > 2 M. Suppression of UO22+ uptake (up to 15%) was observed upon increasing [SO42−] to 4 M, whilst negligible UO22+ uptake suppression was observed with [Cl−] up to 6 M. The impact of Fe3+ concentration on UO22+ extraction under hypersaline conditions ([Cl−] = 22.6 g L−1, 0.64 M) has been studied and behaviour fit to Langmuir and Dubinin-Radushkevich isotherms. Extended X-ray absorption fine structure (EXAFS) studies have been performed to assess the effect of salinity on the uranium coordination environment on the resin and therefore the mechanism of uptake. No change in surface species was observed, with the fit species being uranyl bound by the iminodiacetic acid functional group in a tridentate motif, with an associated bidentate sulfate group. An isotherm model based on this surface species has also been derived. It has been shown that at pH 2 there is little impact of increasing chloride and sulfate concentrations on the extraction behaviour of metals onto Purolite S930+ under the conditions tested. Rather, uranium uptake is more affected by the presence of Fe3+ in solution. As [Fe3+]/[UO22+] is increased from 0 to 2, UO22+ uptake is reduced by up to 66% at aqueous equilibrium.

Cobalt and nickel uptake by silica-based extractants

ABSTRACTThe pKas of ethyl/butyl phosphonate silica (EBP-Si) have been determined, and the removal of cobalt and nickel from solution was investigated as a function of various parameters and compared with those of Purolite S950. pH uptake experiments suggested a combination of ion exchange and acid dissociation of the surface occurring. Isotherm data, fitted using the Langmuir and Dubinin–Radushkevich (D-R) models, indicated that stronger complexes formed with S950 than with EBP-Si. Kinetic data, fitted using a pseudo-second-order model, suggested that the rate-determining process is the reaction of metal ions with the chelating functionality of the resin. Uptake by EBP-Si is two to three times faster than that on S950.

Polyamine functionalised ion exchange resins: Synthesis, characterisation and uranyl uptake

A series of linear polyamine functionalised weak base anion exchange resins have been synthesised using the Merrifield resin and characterised using infra-red spectroscopy, thermogravimetry, elemental analysis and solid state 13C nuclear magnetic resonance spectroscopy. Uptake behaviour towards uranium (as uranyl) from sulfuric acid media has been assessed as a function of pH and sulfate concentration, with comparison to a commercially available weak base anion exchange resin, Purolite S985. Synthetic polyamine resins were seen to outperform the commercial resin at industrially relevant uranyl concentrations, with a trend of increased uptake being seen with increasing polyamine chain length. Uranium loading isotherm studies have been performed and fit with the Langmuir and Dubinin-Radushkevich isotherm models, with a maximum loading capacity observed being 269.50 mg g−1 for the longest polyamine chain studied. Extended X-ray absorption fine structure experiments have been used to determine uranium coordination environment on the resin surface, showing a [UO2(SO4)3]4− species. This coordination knowledge was employed to develop an extraction mechanism and derive an isotherm model based on the law of mass action.

Removal of Cu(II) ions from aqueous solutions by an ion‐exchange process: Modeling and optimization

In this paper, an optimal artificial neural network determined by a self‐adaptive differential evolution approach is applied to model and optimize the removal of copper from wastewater by an ion‐exchange process. The Purolite S930+ resin with iminodiacetic group was used in batch mode for Cu(II) removal from synthetic aqueous solutions in different working conditions (initial solution pH, stirring rate, initial concentration of copper, temperature, contact time and resin amount). The obtained results indicated that the used methodology was able to provide good models for the studied process, the mean squared error in the testing phase obtained by the best network being 0.0034. In addition, the optimal combination of parameters leading to the maximization of removal efficiency determined with the proposed approach was experimentally validated, the prediction being in correlation with the observed data. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 605–612, 2018

Removal of radionuclides from a HCl steel decontamination stream using chelating ion exchange resins – Initial studies

Extraction behaviours of Co(II), Cu(II), Fe(III), Ni(II), U(VI), Th(IV) and Zn(II) mixed metal solutions were examined in chloride media using chelating ion exchange resins Purolite S930+, Purolite S950, Purolite S957 and Dowex M4195 to understand mechanisms of extraction and to identify a potential steel decontamination process to reduce intermediate-level waste volume from nuclear reactor decommissioning. Effects of acidity and ionic strength were considered in batch extraction tests. Breakthrough behaviours were modelled with the Dose-Response model to give an indication to maximum loading capacities. A two-stage process for radioactive steel decontamination is proposed.

Metal recovery from jarosite waste – A resin screening study

ABSTRACTWork has been carried out screening hydrometallurgical resins for application in the valorization of industrially produced jarosite. Of the seven resins tested, anion exchange resins performed poorly for valuable metal recovery. Purolite S950+ and S957, along with a strong acid resin, show good extraction properties, but are selective for Fe3+ over the other (divalent) metals. Purolite S930+ (iminodiacetic acid-functionalized resin) demonstrates selectivity for Cu2+ over Fe3+, but poor selectivity for Ni2+, Zn2+, and Co2+. Dowex M4195 (bispicolylamine-functionalized resin) demonstrates promise for extracting metals of value away from a mixed metal pregnant liquor solution (PLS). A three-stage column-based recovery process is proposed for jarosite leachate treatment.

Study Regarding the Presence of Zn(II) in Thermal Waters for Cosmetic Use

The experimental investigations aimed to determine the optimal conditions for the process of zinc removal from thermal waters with the PUROLITE S920 ion exchange resin. It was determined the residual zinc concentration dependence on the amount of ion exchanger at different initial zinc concentrations in solution and different stirring times. The optimum conditions for achieving a residual concentration below 1 mg/L are: ion exchange rate 1.6 g/L, stirring time about 45 min. The PUROLITE S920 ion exchanger can be successfully used to remove very small amounts of zinc ions from the solution.

Removal of iron ions from industrial copper raffinate and electrowinning electrolyte solutions by chemical precipitation and ion exchange

The reduction of iron ions concentration from copper electrowinning electrolyte solution in copper solvent extraction and electrowinning process, is important to maintain good current efficiency. In this study both chemical precipitation (hydroxide and jarosite) and ion exchange methods were investigated using industrial copper raffinate and electrowinning solutions from Sarcheshmeh copper complex, Iran. Batch precipitation and adsorption tests were initially performed before, a fixed bed column was investigated for iron removal by ion exchange. Batch results indicated that with increasing the pH and dilution, improved the iron removal by chemical precipitation methods. Hydroxide and jarosite precipitations were performed efficiently at pHs of 3 and 2 and temperatures of 70°C and 95°C respectively. The iron removal efficiency was greater with jarosite precipitation (∼70%) compared to hydroxide (∼20%) for a particular pH (2). Diluting by 50% increased the removal efficiency up to 150%. Ion exchange results indicated that pH and dilution did not have a significant effect on the efficiency with this method and it practically performed at ambient temperatures. The batch equilibrium and kinetics experiments were performed with Purolite S957 resin and the results showed that the Sips isotherm (the maximum adsorption capacity was 42mg/g) and both the pseudo-nth order (kad=0.00083mg1−n/g1−n·s and n=1.92) and Langmuir-Freundlich kinetics models (kaLF=0.08mLmin-1mg-1,kdLF=0.12min-1 and n=0.12) were able to predict the equilibrium and kinetics data. In the fixed bed column experiments, the effects of parameters such as the volumetric flow rate and bed height on the breakthrough curves were studied. The iron removal efficiency for the industrial solution which included impurities was less than for synthetic solutions. The results showed that the resin selectively removed the iron ions but did not decrease the copper concentration and used resin was completely regenerated by hydrochloric acid (the amount of 5mL/g of resin and concentration of 30wt%) over several regeneration did not significantly alter the sorption capacity. Finally, a mathematical model based on chemical sorption was used to predict the experimental breakthrough curves data and results showed this model accurately predicted the experimental breakthrough curves. Overall, ion exchange was more efficient at iron removal than chemical precipitation.

The Effects of Hg2+ on Endothelial Function in Electronic Cigarette Smokers with Coronary Artery Disease

The present available data on the harmful effects of electronic cigarettes (EC) is inconsistent and contradicting. Even though EC is considered a healthier alternative to the traditional cigarettes, several studies reported a large range of toxic compounds. The objective of this study is to determine whether the mercury found in the solutions used for electronic cigarettes is involved in the initiation and aggravation of endothelial dysfunction found in smoking persons with coronary artery disease (CAD). Endothelial function was evaluated by performing organ bath studies of vascular rings from patients with CAD, and was determined as a response to cumulative doses of endothelial-dependent/independent vasodilators, in the presence of Hg2+. Hg2+ extraction was realised using ion exchanging resin PUROLITE S920 from the liquid solution used in EC. The results of this study suggests that Hg2+ may be responsible for the aggravation of the endothelial dysfunction found in smoker of EC patients with CAD.

Sorptive separation of molybdenum(VI) from rhenium-containing solutions

It is shown that Purolite S957 cation-exchange resin containing phosphonic-acid and sulfonic groups is capable of selectively sorbing molybdenum(VI) in the presence of rhenium(VII) in solution.

Sorption recovery of rhodium(III) from multicomponent chloride solutions in the presence of tin(II) chloride

The influence of tin (II) chloride additives on sorption of Rh(III) on the Purolite S920 ion exchange resin with isothiouronium groups, the Purolite S985 weak base anion exchange resin, and the Purolite A500 strong base anion exchange resin is investigated. It is established that the introduction of SnCl2 leads to a substantial increase in selectivity of all tested ion exchange resins to Rh(III) and in the sorption rate of Rh(III) on S985 and S920 ion exchange resins. The optimal dosage of SnCl2 (0.01 mol/L) at which the distribution coefficients of Rh(III) during sorption for all tested ion exchange resins reach maximal values is determined. It is shown that almost quantitative recovery of Rh(III) is attained when passing the multicomponent chloride solution of the composition (g/L) 0.2 Rh(III), 72.9 HCl, 53.5 NH4Cl, 2.7 Al(III), 1.23 Fe(III) and 5.9 Sn(IV) with the SnCl2 additive through the Purolite S920 ion exchange resin with isothiouronium groups. Desorption of Rh(III) from the Purolite S920 saturated ionite with the acidified thiourea solution is incomplete, no greater than 60%.

Influence of pH on distribution coefficients of lithium and impurity elements in sorption

The possibility of purifying lithium-containing solutions to remove chemical impurities by sorption in the batch mode was examined. Sulfonic (KU 2-8, Purolite C100, Resinex KW-8), carboxylic (SG-1, Purolite C104FL, Resinex KW-H), and phosphoric acid (Purolite S957) cation-exchange resins were used as sorbents. The distribution coefficients of lithium and impurity elements (sodium, potassium, magnesium, calcium, iron) at different pH values were determined experimentally. The lithium/impurity separation factors were calculated.

Purolite S 940 and Purolite S 950 in heavy metal ions removal from acidic streams

ABSTRACTThe physicochemical properties of Purolite S940 and Purolite S950 were investigated. The kinetic parameters were determined to optimize the sorption process of Co(II) and Ni(II) ions with regard to the influence of chloride ions. Optical microscopy, scanning electron microscopy and electron spectroscopy XPS were used to determine the physicochemical properties of the ion exchangers. They show that Purolite S950 has a greater diversity of beads in terms of volume compared to Purolite S940. Both ion exchangers have a heterogeneous structure on the surface of the beads; however, smooth areas and those with a high porosity can be observed.

Hydration and sorption of amino acids by an iminophosphonic ion exchanger

The interaction of glycine ions and a-alanine with an iminophosphonic Purolite S950 ion exchanger in the protonated form has been studied, and the equilibrium characteristics of ion-exchangeable and nonexchangeable sorption of amino acids have been determined. A quantitative evaluation of the degree of hydration, including the ratios of water with different energies in the phase of the exchanger in the protonated and amino acid forms, has been conducted; the changes in the Gibbs free energy and enthalpies of hydration and dehydration of PuroliteS950 have been determined. It has been found that polyampholyte in the protonated form manifests the greatest sorption capacity during sorption of bipolar amino acid ions. The amount of water of near hydration is the same for hydrogen and alanine forms of the ion exchanger; the greatest changes in the Gibbs energy are observed upon hydration of the alanine form, and those in the enthalpy are found for the hydrogen form of the polyampholyte.