Removal and recovery of gallium and indium lons in acidic solution with chelating resin containing aminomethylphosphonic acid groups

Removal and recovery of gallium and indium ions in acidic solution with the macroreticular chelating resin containing aminomethylphosphonic acid groups was investigated. The resin (RMT-P) exhibited high affinity for gallium and indium ions in sulfuric acid solution. In the column method, gallium and indium ions in sulfuric acid solution (0.05 or 0.5 mol/dm³) were favorably adsorbed on the RMT-P when the solution containing 27.6 mg/dm³ of gallium ion or 51.4 mg/dm³ of indium ion was passed through the RMT-P column at a space velocity of 15 h^?1. The gallium and indium ions adsorbed were eluted by allowing 1 mol/dm³ sodium hydroxide or 4 mol/dm³ hydrochloric acid to pass through the column. The proposed resin appears to be useful for the recovery of gallium and indium ions in sulfuric acid solution.     

Studies of selective adsorption resins. XXV. Preparation of macroreticular chelating resins containing aminomethylphosphonic acid groups from methyl methacrylate/divinylbenzene copolymer beads and their adsorption capacity

Macroreticular chelating resins containing aminomethylphosphonic acid groups were prepared by reaction of methyl methacrylate/divinylbenzene copolymer beads with triethylenetetramine, followed by the reaction of the products with phosphorous acid and formaline. The adsorption capacities of this resin for Cu²⁺, Pb²⁺, Zn²⁺, Ni²⁺, Co²⁺, Ca²⁺, and Mg²⁺ were determined at various pH values. The order of chelate stability for the resin was Cu²⁺ > Pb²⁺ > Zn²⁺ > Ni²⁺ > Co²⁺ > Ca²⁺ > Mg²⁺. Copper, nickel, zinc, calcium, and magnesium ions can be eluted with 1 mol dm^?3 hydrochloric acid. The proposed resin appears to be useful for the removal of Ca²⁺ and Mg²⁺ from salt solution.     

Studies of Selective Adsorption Resins. XXII. Removal and Recovery of Arsenic Ion in Geothermal Power Waste Solution with Chelating Resin Containing Mercapto Groups

Abstract

Removal and recovery of harmful arsenic ion in a geothermal power waste solution with three macroreticular chelating resins containing mercapto groups were investigated. The resin (RES), which was prepared from 2,3-epithiopropyl methacrylate-divinylbenzene copolymer beads, exhibited high affinity for arsenic(III) ion and high resistance against hot water. In the column method, arsenic(III) ion in an aqueous solution was favorably adsorbed on the RES when the sodium arsenite solution (pH 6.2) containing 3 mg/dm³ of arsenic(III) ion was passed through the RES column at a space velocity of 15 h^?1. The arsenic(III) ion adsorbed was eluted by allowing 2 mol/dm³ sodium hydroxide solution containing 5% of sodium hydrogen sulfide to pass through the column. The recycle of adsorption and elution was found to be satisfactory. The RES also exhibited high adsorption ability for arsenic ion in the geothermal power waste solution.     

Treatment of wastewater containing Pb and Fe using ion‐exchange techniques

Treatment of wastewater containing lead and iron was examined using two different ion‐exchange resins namely Duolite ES 467 (containing amino‐phosphonic functional groups) and a chelating ion‐exchange resin (containing hydroxamic acid functional groups). Initially different sorption parameters such as contact time, pH, concentrations of sorbent, sorbate and chloride ion were studied. The sorption kinetics was observed to be fast and equilibrium could be reached within 30 min. Lead sorption efficiency increased with increase in pH whereas the opposite trend was observed with iron. The presence of chloride ions greatly reduced the Pb sorption efficiency in the case of Duolite ES 467. Column studies were carried out to recover Pb and Fe individually using Duolite ES 467 resin. The maximum uptake of Pb at pH 2 and 3 was observed to be 11.63 and 33.96 g dm^?3 of resin respectively. Similarly, for Fe at pH 2 and 3 the uptake was observed to be 10.07 and 6.96 g dm^?3 of resin respectively. In the presence of chloride ions, column studies were carried out using Duolite ES 467 for iron and chelating ion‐exchange resin containing hydroxamic acid functional groups for lead sorption. Hydroxamic acid resin's loading capacity remains constant for at least up to 20 cycles. Copyright © 2005 Society of Chemical Industry     

L-抗坏血酸-2-磷酸酯镁的合成与纯化

L-抗坏血酸与丙酮反应生成5，6-0-异丙叉-L-抗坏皿酸（IAA)，再与三氯氧磷进行磷酰化反应．往反应混合液中加入等体积的95％醇，再加入CaCl2溶液，以沉淀出L-抗坏血酸-2-磷酸酯钙晶体；把制得的钙盐溶解在搅拌的阳离子交换树脂的悬浮液中，然后通过阳离子交换柱以除去金属离子．在pH=9下转化为L-抗坏血酸-2-磷酸酯镁，收率为68．2％(以IAA计)，     

Preparation of macroreticular chelating resins containing dihydroxyphosphino and/or phosphono groups and their adsorption ability for uranium

The macroreticular chelating resins (RSP, RSPO, RCSP, and RCSPO) containing dihydroxy-phosphino and/or phosphono groups were prepared and their adsorption capacity for UO₂²⁺ and the recovery of uranium from sea water were investigated. RSP and RCSP were prepared by phosphorylation of macroreticular styrene–divinylbenzene copolymer beads and the chloromethylated copolymer beads, respectively. RSPO and RCSPO were prepared by oxidation of RSP and RCSP, respectively. The order of recovery of uranium from sea water with these four resins is as follows: RCSPO ? RCSP > RSPO > RSP. The adsorption of uranium in sea water was not only affected by the chemical structure, but also by physical structure of the resins. Uranium absorbed on the resins was eluted with 0.25 ～ 1 mol·dm^?3 Na₂CO₃ or NaHCO₃ solution by batch and column methods. The average recovery ratios of uranium from sea water with Na-form and H-form RCSP on 10 recycles were 84.9% and 90.5%, respectively, when 20 dm³ of sea water was passed through the column (resin 4 cm³, 10 mm ? × 50 mm) at the space velocity of 60 h^?1. RCSP has a high physical stability and resistance against acid and alkali solution.     

Cyanide detoxification by selective ion exchange with protonated poly(4-vinyl pyridine)

In order to explore the possibility of using cross-linked poly(4-vinyl pyridine), PVP, for selective removal of cyanide in waste water by complexation of the cyanide with ferrous ion followed by ion exchange, the sorption behaviour of the anionic ferrocyanide complex (Fe(CN)₆^4-) on the resin operating in an acid salt form has been studied. The results are compared with those obtained on a conventional gel-type weak base resin, Amberlite IRA-68. The ferrocyanide complex is selectively sorbed in preference to other common ions and is readily stripped with dilute sodium hydroxide. PVP has a high sorption capacity, fast sorption kinetics and a rapid rate of regeneration, being much superior to Amberlite IRA-68 in all these respects. The sorption rate is film-diffusion controlled at low solution concentrations (< 0.8 mmol litre^?1) and particle-diffusion controlled at higher concentrations (> 0.8 mmol dm^?3). Lowering pH to ～ 1 increases the sorption of Fe(CN)₆^4? on to protonated PVP by 75% over that at pH 7, a phenomenon explained by the formation of protonated ferrocyanide species, HFe(CN)₆^3- and H₂Fe(CN)₆^2-. From column operations with 156 mg dm^?3 cyanide waste stream a capacity of 73 mg CN^? g^?1 of protonated PVP to 1 mg dm^?3 breakthrough is determined, compared to 60 mg CN^? g^?1 of protonated IRA-68.     

The use of a rotating cylinder electrode to selective recover palladium from acid solutions used to manufacture automotive catalytic converters

The reduction of palladium, rhodium and neodymium ions at concentrations of 0.94, 0.97 and 0.69 mol dm⁻³, respectively was studied in 1 mol dm⁻³ HNO₃ or 1 mol dm⁻³ HCl, at a stainless steel and a vitreous carbon electrode, at 25 °C. At a vitreous carbon electrode in a solution containing rhodium and palladium ions in 1 mol dm⁻³ HCl electrolyte, the reduction of metal ions occurred at a similar potential to the formation of hydrogen gas, which impeded the selective separation of the two metals. At a stainless steel cathode in 1 mol dm⁻³ HNO₃, palladium deposition occurred at a potential ≈0.35 V less negative than that of rhodium allowing the selective recovery of palladium. Neodymium ions were not electroactive in acidic chloride or nitrate media at pH 0. Using a solution obtained from a catalytic converter manufacturer containing palladium, rhodium and neodymium ions in 1 mol dm⁻³ HNO₃, palladium ions were preferentially removed at 0.15 V versus SHE at an average cumulative current efficiency of 57%.     

Cell recycle and broth reuse fermentation with cross-flow filtration and ion-exchange resin

A novel integrated fermentation system in which cross-flow filtration was coupled to an anion-exchange resin column was developed to achieve biomass recycle and broth reuse for lactic acid fermentation. An anion-exchange resin column was employed to recover lactic acid from the spent broth. The effluent was diluted with fresh medium, supplemented with glucose and nutrients. Spent broth was reused for three consecutive biomass recycle fermentations with no significant decrease in fermentation performance. The fermentation system enabled simultaneously high productivity of lactic acid (average value 7·75 g dm⁻³ h⁻¹ and total amount of lactic acid produced 85·21 g dm⁻³ after 11 h fermentation), high productivity of cells (average value 2·00 g dm⁻³ h⁻¹) and efficient utilization of medium (about 75% of the spent broth was reutilized). The system described may be applied to other organic fermentations subject to end-product inhibition.     

Determination of the efficiency and removal mechanism of cobalt by crab shell particles

The effects of contact time, solution pH and ionic strength on interactions between cobalt (⁵⁹Co) ions in synthetic liquid waste and particles of raw crab shell, Portunus trituberculatus, in batch reactions were studied. Approximately 19.5 mg dm^?3 Co was removed within 6 h after contact with 1.0 g dm^?3 crab shell at an initial concentration of 20 mg dm^?3 Co. Due to the dissolution of calcium carbonate in the crab shell, the solution pH changed spontaneously to 10, leading to precipitation of cobalt ions. The efficiency of cobalt removal depended on solution pH, but was less pH sensitive than for controls without crab shell. The maximum uptake of Co at an initial pH value of 5.0 was 510 mg g^?1 crab shell. The removal efficiency was affected slightly by ionic strength up to 2.0 mol dm^?3 of NaCl. Scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) indicated that the removal mechanism of Co by crab shell resulted primarily from the dissolution of calcium carbonate followed by precipitation of cobalt on the surface of the shell. Compared with commonly used ion‐exchange resins such as natural zeolite, Durasil 70, and Durasil 230, the efficiency of Co removal by a column of mixture of crab shell and activated carbon was at least three‐fold greater, indicating that crab shell is a suitable biosorbent for the removal of cobalt from liquid waste. Copyright © 2004 Society of Chemical Industry     

Recovery of uranium from seawater V. Preparation and properties of the macroreticular chelating resins containing amidoxime and other functional groups

We have synthesized macroreticular chelating resins containing amidoxime groups from acrylonitrile (AN)-divinylbenzene (DVB)-alkyl acrylate, alkyl methacrylate, or vinylpyridine (VPy) copolymer beads. It was found that the chelating resin (RNMH)-containing amidoxime groups prepared from AN-DVB-methyl acrylate (MA) indicated the highest adsorption ability for uranium in seawater. Hydroxamic acid and carboxylic groups in addition to amidoxime groups were formed during the reaction of the copolymer beads with a methanol solution of hydroxylamine. The adsorption ability for uranium was greatly influenced by the physical pore structure (macropore) and the pore structure formed by the swelling(micropore). RNMH (RNMH10-10) prepared with 10 mol% of DVB and 10 mol% of MA had the highest adsorption ability and physical stability for uranium. On the other hand, improved adsorption ability for uranium was not observed in the case of the macroporous resins (RNPyH) prepared by the copolymerization of VPy as the basic component. After seawater was passed through the column packed with RNMH10-10 at a space velocity (SV) of 180 h^?1 (up-flow) for 10 days, the amount of uranium adsorbed on the resin was about 100 mg/dm³-R and 260 mg/kg-R.     

Displacement Band Chromatography of Hydrogen Sulfites for Enrichment of Sulfur Isotopes

Abstract

Experimental studies were conducted on the enrichment of sulfur isotopes by displacement band chromatography. In these studies, a band of hydrogen sulfite (bisulfite) ions from a sulfurous acid or bisulfite-salt solution was continuously displaced by bisulfate ions from a sulfuric acid or bisulfate-salt solution in a column packed with aminated polystyrene-divinyl benzene resin under varied process conditions. The sulfur isotopes were enriched through isotopic exchange between the bisulfite ions on the resin and the sulfurous acid and/or bisulfite-salt solution in contact with the resin within the moving band. During the isotopic exchange, S-34 isotope was favored in the resin phase and S-32 isotope in the liquid phase. As a result, the S-34 isotope was gradually enriched at the rear of the band, and S-32 isotope at the front. The effects of the various process conditions were evaluated on separative power, height equivalent to a theoretical plate, and operational simplicity. The highest separative power, 3.05 g S-34/cm³/yr, was achieved with an ammonium bisulfite feed displaced by a sulfuric acid displacer at 65°c operating temperature.     

High-efficiency HFSLM for silver-ion pertraction from pharmaceutical wastewater and mass-transport models

Hollow fiber supported liquid membrane (HFSLM) is a favorable technique for the pertraction of metal ions, especially at very low metal concentration. In this work, the pertraction of silver ions from acidic pharmaceutical wastewater via HFSLM was investigated. Pharmaceutical wastewater containing 30 mg/dm³ of silver ions and 120 mg/dm³ of ferric ions was subjected to HFSLM as a feed solution. LIX 84-I dissolved in organic solvent together with Na₂S₂O₃·5H₂O solution was selected for use as a liquid membrane and a receiving solution, respectively. The influence of ferric ions on the pertraction of silver ions was studied firstly using wastewater with normal ferric ion concentration and secondly using wastewater with ferric ion precipitation by phosphoric acid solution. The highest pertraction of silver ions was achieved by using 0.1 M of LIX 84-I and 0.5 M of Na₂S₂O₃·5H₂O solution at pH of feed and receiving solutions of 3.5 and 2. The flow rates of feed and receiving solutions were 0.2 dm³/min. 0.6 mg/dm³ of silver ions that remained in the wastewater was below the mandatory discharge limit. No effect of normal ferric ion concentration in the wastewater on silver ion pertraction was observed. The crucial parameters were defined to confirm the efficiency and reliability of the system. Finally, the controlling transport regime of silver ion pertraction across HFSLM was determined by the diffusion flux and reaction flux models.     

Copper-selective chelating resins. II. Column extractions

Two chelating resins based on poly(glycidylmethacrylate-co-ethyleneglycol dimethacrylate) and two based on poly(styrene-co-divinylbenzene) have been used in small-scale column extractions of Cu(II) from sulphate solutions containing 1.0 mg l⁻¹ of metal ion at pH 5. Two of the resins bearing 2-aminomethylpyridine residues with saturation capacities up to ∼ 15 g Cu(II) l⁻¹ resin showed sharp breakthrough profiles and rapid exchange kinetics. The other two with higher ligand loading displayed shallow profiles and did not reach saturation capacity, indicating a significant proportion of the ligand groups to be inaccessible under the conditions employed. For a column of 10 ml bed volume, increasing the flow rate of the feed solution from 1 ml min⁻¹ progressively to 30 ml min⁻¹, using one of the more efficient resins, showed that above a rate of ∼ 5 ml min⁻¹ the bulk movement of ions through the column was too fast for all the resin-bound ligands to be accessed. As a result breakthrough moved to lower volumes and the working capacity dropped. No difference was found in the elution of all four resins with 1 M H₂SO₄ at a flow rate of 1 ml min⁻¹. In all cases Cu(II) was rapidly and efficiently eluted from the column.The selectivity properties of the two efficient resins in extracting Cu(II) ions from a solution containing a large excess of Zn(II) ions were also investigated. The effect of a 250-fold excess of Zn(II) proved negligible in both cases, and Cu(II) was rapidly and selectively extracted with a separation factor of ∼ 900: 1 in the case of the polystyrene-based resin, and ∼ 500: 1 in the case of the methacrylate-based species.In terms of kinetic performance and metal ion selectivity (in both loading and elution) the results of the batch extraction experiments were confirmed in these column tests, hence proving the predictive value of careful batch testing. On considering kinetic factors, capacity factors and metal ion selectivity factors, a resin carrying a 2-aminomethylpyridine group attached to a polymethacrylate backbone proved to be the optimum one.     

Preparation and Adsorption Properties of λ-MnO2-Cellulose Hybrid-Type lon-Exchanger for Lithium Ion. Application to the Enrichment of Lithium Ion from Seawater

Abstract

spherical beads of a hybrid-type ion-exchanger (HIE) have been prepared by dispersing microcrystalline λ-MnO2 in macroporous cellulose gel beads. The beads were 0.1 to 0.3 mm in diameter and contained 0.71 g λ-MnO2/g dry HIE. The ion-exchange behaviors of HIE for lithium and sodium ions were investigated by batch and column methods. The uptakes for lithium and sodium ions were 2.8 and 0.1 mmol/g dry HIE, respectively, at pH 12.3 by the batch method and 1.0 and 0.1 mmol/g dry HIE at pH 11.6-11.8, respectively, by the column method. When 1.52 L seawater was passed through a column containing 0.05g wet HIE at a flow rate of 0.3 mL/min, 2.0 mg lithium/g dry HIE was recovered, indicating that the enrichment ratio for lithium ion was 1.3 × 10⁴ mL/g and the enrichment factors for lithium ion to sodium, potassium, calcium, and magnesium ions were 7.1 × 10⁴, 1.7 × 10³, 1.0 × 10³, and 6.9 × 10³, respectively.     

Transport of cadmium and iron through a carboxylic membrane based on a poly(vinyl chloride)/poly(methyl methacrylate‐co‐divinyl benzene) system

The transport of cadmium and iron through a poly(vinyl chloride)/poly(methyl methacrylate‐co‐divinyl benzene) carboxylic ion‐exchange membrane was investigated with a system containing HCl as the receiver solution and CdCl₂ or FeCl₃ as the feed solution. Transport of the ions through the membrane depended on the H⁺ concentration in the receiver solution and the metal concentration in the feed solution. The rate of transfer for cadmium was about 35% higher than that for iron under the same conditions (0.5 mol/dm³ of HCl, 0.1 mol/dm³ of CdCl₂ or FeCl₃, and 5 h of dialysis). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 705–707, 2005     

Synthesis and optimization of copper sulfide‐coated electrically conducting poly(acrylonitrile) fibers

In this research work, coating of acrylic fibers (fibers spun from poly acrylonitrile) with copper sulfide was investigated. Surface of the acrylic fibers were coated with an insoluble conducting copper sulfide layer. One‐step dipping method was carried out. Acrylic fibers were treated in a bath containing divalent copper ions, a reducing agent, which is capable of reducing the divalent copper ions to a monovalent copper ions and a sulfur‐containing compound. This treatment resulted in a reduction of electrical resistance to 1 × 10⁹ that of an almost infinite resistance for the untreated fibers. The influence of some parameters such as concentration of copper (II) sulfate, hydroxylamine sulfate, sodium thiosulfate, and temperature of treatment bath were also investigated. A second reducing material such as sodium dithionite was used to improve the electrical conductivity of the fibers. The amount of reacted copper was measured by atomic absorption technique. The surface properties of the coated‐acrylic fibers were studied using scanning electron microscopy (SEM). Within the experimental conditions, a solution containing 1.2 g/dm³ copper (II) sulfate, 1.6 g/dm³ hydroxylamine sulfate, 3.6 g/dm³ sodium thiosulfate, and 3 g/dm³ sodium dithionite was selected as a suitable formulation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Formation and reactivity of oxides and basic salts. II. Radio-isotope studies of some calcareous materials

Rates of calcium exchange between solid and solution in the ageing of hydrated lime and of calcium carbonate samples have been determined using calcium-45 radio-isotope. After a comparatively rapid calcium uptake of about 1 molecular layer at the hydrated lime surface, the exchange rate diminishes as the ions need to diffuse more deeply into the hydrated lime structure. Results for calcium carbonate samples of widely different specific surfaces are compatible with very slow ageing in water. Rates of gypsum precipitation from radioactive calcium chloride and nitrate solutions have been compared in neutral and acidic media and in the presence of albumen. Lower gypsum saturation ratios are established ultimately in neutral rather than acidic media, particularly in solutions containing no salts other than gypsum. Solid hydrated lime reacts rapidly with dilute sulphuric acid, aluminium and magnesium sulpnates, magnesium chloride or sea-water, releasing calcium ions into solution. The radioactivities of the solutions decrease subsequently as gypsum separates out or calcium ions are adsorbed by the finely-divided magnesium hydroxide precipitated. At higher magnesium salt concentrations, the calcium-45 radioactivity does not initially increase so sharply. This is ascribed to basic salt formation preventing all of the lime from going quickly into solution.     

Separation of Electrochemically Generated Ce(IV) from Rare Earths(III) in Nitric Acid Media by TBP Impregnated Resin

Abstract

Electro‐oxidation of Ce(III) to Ce(IV) in nitric acid media at different anode materials with high oxygen evolution overpotential was carried out. Ce(IV) nitrato complexes were adsorbed on a novel resin, based on porous silica beads with immobilized polystyrene/DVB copolymer, that was impregnated with tri‐n‐butyl phosphate (TBP). Under the studied conditions, Ce(IV) sorption increased with increasing nitric acid concentration (0.5–6 mol · dm^?3). Oxidation of sorbent by adsorbed Ce(IV) species resulting in Ce(III) release to the solution was observed and thoroughly evaluated. In spite of problems with TBP leakage (12%), column separation of pure Ce(IV) from Y(III) and La(III) was achieved in 6 mol · dm^?3 HNO₃ at 288 K. Ce(IV) breakthrough capacity was 0.48 mol · kg^?1‐TBP. Column regeneration with 0.1 mol · dm^?3 nitric acid yielded Ce solution with purity higher than 99.99 wt.% with respect to La and Y impurities.     

Immobilized resins and liquid extractants for potassium extraction from concentrated brines

Extraction of potassium ions from concentrated chloride solutions of alkali and alkaline-earth cations with Cyanex^® 301 [bis(2,4,4-trimethylpentyl)dithiophosphinic acid] and a crown ether has been studied. The extractant was used in toluene solution or supported on a styrene-divinylbenzene resin (1.5 % crosslinked) and showed synergistic behaviour and high preference for potassium over sodium, magnesium and calcium.