Studies of selective adsorption resins. XXVI. Removal of calcium and magnesium ions in a salt solution with chelating resin containing aminomethylphosphonic acid groups

Removal of calcium and magnesium ions in a salt solution with the macroreticular chelating resin containing aminomethylphosphonic acid groups was investigated. The resin (RMT-P) exhibited high affinity for calcium and magnesium ions in a salt solution containing 200 g/dm³ of sodium chloride. In the column method, calcium and magnesium ions in a salt solution were preferentially absorbed on the RMT-P, when the salt solution containing 100 mg/dm³ of calcium or magnesium ion was passed through the RMT-P column at a space velocity of 15 h^?1. The calcium and magnesium ions adsorbed were eluted by allowing 1 mol/dm³ hydrochloric acid to pass through the column. The recycle of adsorption and elution was found to be satisfactory.     

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.     

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%.     

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     

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.     

Conversion of soybean oil into ion exchange resins: Removal of copper (II), nickel (II), and cobalt (II) ions from dilute aqueous solution using carboxylate‐containing resin

An ion‐exchange resin containing carboxylic acid groups was prepared by reaction of epoxidized soybean oil with triethylene tetramine, followed by hydrolysis of glycerides by using sodium hydroxide solution. The cation exchange capacity of the resins was determined to be 3.50 mequiv/g. The adsorption capacity for Cu²⁺, Ni²⁺, and Co²⁺ on the obtained resin at pH 5.0 was found to be 192, 96, and 78 mg/g, respectively. Effect of pH on the adsorption capacity for copper (II), nickel (II), and cobalt (II) ions were also studied. Cu²⁺, Ni²⁺, and Co²⁺ were adsorbed at a pH above 3. These metal ions adsorbed on the resin are easily eluted by using 1N HCl solution. The selectivity of the resin for Cu²⁺ from mixtures containing Cu²⁺/Co²⁺/Ni²⁺ ions in the presence of sodium chloride was also investigated © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2386–2396, 2002     

Sorption Behavior of In(III) Ions onto Cation-Exchange Carboxylic Resin in Aqueous Solutions: Batch and Column Studies

Indium and its compounds have numerous industrial applications in the manufacture of liquid crystal displays and semiconductors. They are considered hazardous substances. This article reports the research into the recovery of In(III) from aqueous solution by sorption. Cation-exchange carboxylic resin (D155 resin) was used as a sorbent for indium(III) ions extraction in this research. The factors of parameters, such as pH, kinetics, temperature and sorption isotherm, and column experiment were investigated. In batch system, D155 resin exhibited the highest In(III) ion uptake as 279 mg/g at 298 K with a pH value 5.00. The sorption data matched the Langmuir isotherms very well. The thermodynamic parameter ΔG was negative, and this result indicated that the sorption of In(III) ions on D155 resin was spontaneous. Furthermore, the positive value of ΔH showed that the sorption was endothermic in nature. In(III) ions can be eluted with 0.5 mol/L HCl solution. The Thomas model was applied to experimental column data to determine the characteristic parameters of the column which is useful for process design.     

Recovery of Sinapic Acid from the Waste Effluent of Mustard Protein Isolation by Ion Exchange Chromatography

Sinapic acid present in the waste stream of yellow mustard protein isolation was purified by strong base Dowex (1 × 8, Cl^?) ion exchange chromatography. The ratio of loading volume to resin bed volume was 19:1. Approximately 80 % of sinapic acid was adsorbed. The column was washed with two bed volumes of water to remove remaining undesirable components. Approximately 75 % of sinapic acid adsorbed by the resins in the column was eluted by ten bed volumes of a solution containing 0.9 M acetic acid and methanol (4:6, v/v). Up to 15 adsorption and regeneration cycles resulted in only a slight, 3–5 %, reduction in ion exchange capacity, indicating that this is a viable approach to the recovery and purification of sinapic acid. The recovery of this valuable nutraceutical ingredient improves the economic viability of an integrated extraction process for this Canadian oilseed crop.     

LX-92树脂对硫酸体系低浓度镓离子的动态吸附

研究了粉煤灰模拟硫酸浸出液中的镓在聚苯乙烯树脂(LX-92)上吸附分离的可能性,采用固定床吸附装置考察了树脂动态吸附-脱附镓的行为,利用Thomas,Yoon-Nelson和Adam-Bohart经验模型对动态吸附过程进行了分析和预测.结果表明,降低流速(F)、增加床层高度(Z)、减小镓(Ⅲ)初始浓度(C0)有助于提高...     

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     

Adsorption mechanism of heavy-metal ion by microspherical tannin resin

The spherical tannin resin (STR) resulting from the reaction between Mimosa (Acacia Mollissima) tannin (condensed-type tannin) and formaldehyde was very porous. The specific surface area of the STR made from 37.5% of tannin was 139.2 m²/g (1 g of the resin in this is wet resin corresponding to 1 g of dried resin). Properties such as specific surface area and average pore radius could be controlled by adjusting the tannin concentration. The apparent activation energy of Cu²⁺ ion adsorption by STR was 3 kcal/mol, and that of Cr⁶⁺ ion was 2 kcal/mol. Since the energy was small, we concluded that the adsorption of metal ions was not influenced significantly by the adsorption temperature. The heat of adsorption for Cu²⁺ ions was only 1.6 kcal/mol, which suggests that the adsorption was a physical phenomenon. It was thought that the diffusion of heavy-metal ions into the porous resin was the rate-determining step of the adsorption since the elution profile of the column method was analogous to the profile of active carbon, which adsorbs physically, the heavy metal ions gradually leaking through the column. The surface and cross section of the STR were observed before and after Cu²⁺ ion adsorption with the scanning electron microscope. The pores of the spherical resin were clogged with adsorbed copper, suggesting that the Cu²⁺ ions were adsorbed during the formation of a multimolecular layer. The adsorption may therefore have been due to physical attractive forces. The rate of adsorption and adsorption isotherms of Cu²⁺ ions from copper salts having various anions was found to vary depending on the type of anion. These phenomena were not thought to be due to the properties of the spherical resin but to differences in the hydration state of copper ions.     

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.     

Synthesis,Characterization, and Applications of a New Chelating Resin Containing 4-2-(Thiazolylazo) Resorcinol (TAR)

A new phenol–formaldehyde based chelating resin containing 4-(2-thiazolylazo) resorcinol (TAR) functional groups has been synthesized and characterized by Fourier transform infrared spectroscopy and elemental analysis. Its adsorption behavior for Cu(II), Pb(II), Ni(II), Co(II), Cd(II), and Mn(II) has been investigated by batch and column experiments. The chelating resin is highly selective for Cu(II) in the pH range 2 ～ 3, whereas alkali metal and alkaline earth metal ions such as Na(I), Mg(II), and Ca(II) are not adsorbed even at pH 6. Quantitative recovery of most metal ions studied in this work except Co(II) is achieved by elution with 2M HNO₃ at a flow rate of 0.2 mL min^?1. A similar trend is observed for distribution coefficient values. The quantitative separations achieved on a mini-column of chelating resin include Cd(II) – Cu(II), Mn(II) – Pb(II), Co(II) – Cu(II), Mn(II) – Ni(II), and Mn(II) – Co(II) – Cu(II). The recovery of copper(II) is quantitative (98.0–99.0%) from test solutions (10–50 mg/L) by 1 mol/L HNO₃-0.01 mol/L EDTA. The chelating resin is stable in acidic solutions below 2.5 M HNO₃ or HCl as well as in alkaline solution below pH 11. The adsorption behavior of the resin towards Cu(II) was found to follow Langmuir isotherm and second order rate.     

Preferential extraction of gallium from Bayer liquor using ion exchange chelating resin containing hydroxamic acid functional group

Gallium extraction studies were carried out using resin containing an hydroxamic acid functional group. Extraction was dependant on reaction time and alkali concentration. The resin did not extract aluminium. Vanadium extraction kinetics were slower than those of gallium. The gallium and vanadium separation efficiency increased with decreasing contact time with extractions of 64% and 32% respectively after 1 min. Gallium extraction was independent of alkali concentration up to 250 g dm^?3 and thereafter decreased with increasing alkali concentration. Vanadium extraction decreased with increasing alkali concentration. Cyclic batch and column studies were carried out with synthetic as well as actual Bayer liquor to test the stability and preferential extraction of gallium using the resin. It was observed that using resin partially loaded with gallium, the co‐extraction of vanadium could be minimised. Copyright © 2003 Society of Chemical Industry     

EXTRACTION OF MOLYBDENUM(VI) BY PRIMENE JMT

ABSTRACT

Distribution of molybdenum (VI) between aqueous sulfuric acid solution and an organic solution containing Primene JMT has been studied.

The aqueous solutions consist of ammonium molybdate with acid concentration in a pH range 2 - 6.5, the concentration of amine in the organic phase being 0.1 mol/dm³ in benzene. The presence of various species in the aqueous phase is considered and the equilibrium composition of substances in the organic phase is determined. The extraction mechanism is discussed.     

A simple sulfuric acid pretreatment method to improve the adsorption of Cr(VI) by chitosan

An optimum pH of 5.0 for the adsorption of Cr⁶⁺ by chitosan was determined by using a stirred‐batch reactor method at constant pH. When a column containing chitosan was used to bind Cr⁶⁺ in a situation where pH could not be held constant because of pH changes caused by the chitosan itself, significant binding occurred only at solution pH 1 and 2. When chitosan was pretreated with sulfuric acid in a range of 7–70 mol % sulfuric acid : moles glucosamine residue, maximum binding occurred at pH 6.0. Under these conditions, a column containing 0.500 g acid‐treated chitosan (35% mole ratio) reduced the concentration of Cr⁶⁺ in 713 bed volumes of 25 ppm Cr⁶⁺ solution to ≤5 ppm in the effluent. A similar column of pretreated chitosan reduced Cr⁶⁺ concentration in 1042 bed volumes of industrial chromium plating rinse water initially containing 18 ppm Cr⁶⁺ to ≤5 ppm. Capacity experiment results indicated 60 mg chromium bound per gram of treated chitosan at pH 6.0. Commercial resin IRA‐67 was also investigated as a Cr⁶⁺ binding agent. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2808–2814, 2004     

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.     

Extraction separation of Ir(III) and Rh(III) with Cyanex 923 from chloride media: a possible recovery from spent autocatalysts

Liquid–liquid extraction of Ir(III) and Rh(III) with Cyanex 923 from aqueous hydrochloric acid media has been studied. Quantitative extraction of Ir(III) was observed in the range of 5.0–8.0 mol dm^?3 HCl with 0.1 mol dm^?3 Cyanex 923, while Rh(III) was extracted quantitatively in the range of 1.0–2.0 mol dm^?3 HCl with 0.05 mol dm^?3 Cyanex 923 in toluene along with 0.2 mol dm^?3 SnCl₂. The Ir(III) was back extracted with 4.0 mol dm^?3 HNO₃ quantitatively from the organic phase while Rh(III) was stripped with 3.0 mol dm^?3 HNO₃. The extraction of Rh(III) with Cyanex 923 was not quantitative without use of SnCl₂. However in the extraction of Ir(III) a negative trend was observed in the presence of SnCl₂. Varying the temperature of extraction showed that the extraction reactions of both the metal ions are exothermic in nature, and the stoichiometric ratio of Ir(III)/Rh(III) to Cyanex 923 in organic phase was found to be 1:3. The methods developed were applied to the recovery of these metal ions from a synthetic solution of similar composition to that from leaching of spent autocatalysts in 6.0 mol dm^?3 HCl. © 2002 Society of Chemical Industry