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1.
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.  相似文献   

2.
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.  相似文献   

3.
《分离科学与技术》2012,47(18):3545-3554
Abstract

Macroporous chelating resins containing polyol groups (RGB) were prepared by the reaction of poly(glycidyl methacrylate) beads with 2-amino-Zhydroxy-methyl-I,3-propanediol, and the behavior of the resulting RGB in the uptake of boric acid was studied. The RGB exhibited high affinity for boric acid in the pH range of 5 to 9 and took up boric acid selectively from geothermal power waste solutions in which various minerals were contained. The boric acid adsorbed on the RGB was easily eluted with I mol/dm3 hydrochloric acid.  相似文献   

4.
Some attempts were made to recover gold from aqueous systems using immobilized persimmon tannin. This adsorbent adsorbed gold from solutions containing hydrogen tetrachloroaurate(III) with high efficiency, whereas there was minimal adsorption from solutions containing gold(I) sodium thiomalate and sodium dicyanoaurate(I). The adsorption of gold was rapid, and was affected by the pH of the solution, temperature, external gold concentration and amount of adsorbent. Adsorbed gold was easily desorbed with 1 mol dm?3 thiourea solution, indicating that immobilized persimmon tannin can be repeatedly re-used for the recovery of gold using adsorption-desorption cycles.  相似文献   

5.
《分离科学与技术》2012,47(2):173-184
Abstract

Trace levels of aqueous arsenic(III) and (V) ions were adsorbed selectively onto the ferric complex of a chelating resin, Uniselec UR-10. The adsorption was markedly dependent upon the pH of the aqueous phase. The distribution ratio and the specific adsorption capacity of arsenic(III) were 23,000 and 0.47 mmole/g, respectively, at the optimum pH for the adsorption, 9.2. The corresponding values of arsenic(V) were 22,000 and 0.53 mmole/g at the optimum pH 5.5. In the column operation the adsorption of the arsenic ions was also dependent upon the flow velocity and the size of the resin particle. A velocity of 60 cm/hr and 100 to 200 mesh size afforded satisfactory results. Adsorbed arsenic was recovered quantitatively by eluting the resin with 2 N hydrochloric acid, where the complexed iron was also eluted. A trace level of arsenic in wastewater from a geothermal power plant was successfully separated in the presence of a large excess of diverse cations and anions. Trace arsenic in natural seawater was also successfully preconcentrated 100 to 200 times over the original level by adsorption onto the ferric resin followed by elution with hydrochloric acid.  相似文献   

6.
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.  相似文献   

7.
《分离科学与技术》2012,47(12):2767-2786
Abstract

Chitosan coated perlite beads are prepared by drop‐wise addition of a liquid slurry containing chitosan and perlite to an alkaline bath. The resulting beads are characterized using FTIR, SEM, EDXRF, and Surface area analysis and the chitosan content of the beads is 23% as determined by a pyrolysis method. Adsorption of Co (II) metal ions from aqueous solution on chitosan coated perlite beads is studied under both equilibrium and dynamic conditions. In the present investigation, a first order reversible rate equation is used to understand the kinetics of metal removal and to calculate the rate constants at different initial concentrations. The equilibrium characteristics of metal ion on newly developed biosorbent are studied and the experimental adsorption data are well fitted to Freundlich and Langmuir adsorption isotherm models and the model parameters are evaluated. The effect of pH, agitation time, concentration of adsorbate, and amount of adsorbent on the extent of the adsorption are investigated. The sorbent loaded with metal is regenerated with 0.10 mol dm?3 sodium hydroxide solution. The adsorption desorption cycles indicated that the chitosan coated perlite could be regenerated and reused to remove Co (II) from waste water.  相似文献   

8.
The aim of this work was a comprehensive study of the oxidative and sorptive properties of a hybrid polymer containing manganese oxide toward As(III) and As(V). A poly(styrene‐divinylbenzene) copolymer containing oxidative functional groups (? SO2NBrNa) was used as the supporting material for MnO2. The inorganic component was deposited as a result of the oxidation reaction of Mn(II) with oxidative groups of the host polymer. The surface of the polymer matrix was evenly covered with a thin layer of manganese oxide. The obtained product (R/S/Mn) exhibited high oxidative capacity over a wide pH range (2–12); however, under acidic and neutral conditions, the reaction ran significantly faster. The studied material shows some sorption properties but its sorption capacity is much lower than its oxidation capacity. The treatment, in a column regime, of the arsenic solution containing 1 mg As(III) dm?3 and coexisting ions in concentrations similar to those in natural waters, confirmed the excellent oxidation capacity of the obtained product. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39489.  相似文献   

9.
The removal behavior of fluoride ions was examined in aqueous sodium fluoride solutions using a titanium hydroxide-derived adsorbent. The adsorbent was prepared from titanium oxysulfate (TiOSO4·xH2O) solution, and was characterized by X-ray diffraction, scanning electron microscopy, thermogravimetry-differential thermal analysis, Fourier transform infrared spectrum and specific surface area. Batchwise adsorption test of prepared adsorbent was carried out in aqueous sodium fluoride solutions and real wastewater containing fluoride ion. The absorbent was the amorphous material, which had different morphology to the raw material, titanium oxysulfate, and the specific surface area of the adsorbent (96.8 m2/g) was 200 times higher than that of raw material (0.5 m2/g). Adsorption of fluoride on the adsorbent was saturated within 30 min in the solution with 200 mg/L of fluoride ions, together with increasing pH of the solution, due to ion exchange between fluoride ions in the solution and hydroxide ions in the adsorbent. Fluoride ions were adsorbed even in at a low fluoride concentration of 5 mg/L; and were selectively adsorbed in the solution containing a high concentration of chloride, nitrate and sulfate ions. The adsorbent can remove fluoride below permitted level (< 0.8 mg/L) from real wastewaters containing various substances. The maximum adsorption of fluoride on the adsorbent could be obtained in the solution at about pH 3. After fluoride adsorption, fluoride ions were easily desorbed using a high pH solution, completely regenerating for further removal process at acidic pH. The capacity for fluoride ion adsorption was almost unchanged three times after repeat adsorption and desorption. The equilibrium adsorption capacity of the adsorbent used for fluoride ion at pH 3 was measured, extrapolated using Langmuir and Freundlich isotherm models, and experimental data are found to fit Freundlich than Langmuir. The prepared adsorbent is expected to be a new inorganic ion exchanger for the removal and recovery of fluoride ions from wastewater.  相似文献   

10.
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.  相似文献   

11.
A porous resin loaded with monoclinic or cubic hydrous zirconium oxide was prepared by incorporation of ZrOCl2·8H2O into porous spherical polymer beads followed by hydrolysis and hydrothermal treatment of the zirconium salt. Hydrous zirconium oxide appeared to deposit inside the pores with relatively large diameter. The adsorption capacity and distribution coefficients for As(III) and As(V) were determined by batch procedures. The hydrous zirconium oxide-loaded resin (Zr resin) showed a strong adsorption for As(V) at slightly acidic to neutral pH region while As(III) was favorably adsorbed at pH around 9 to 10. The removal of low concentrations of arsenic from the model effluents to meet the demand of Japanese industrial effluent standard (0.1 ppm) was successfully achieved by the column operation packed with the Zr resin. The Zr resin was regenerated by treatment of the column with 1 M sodium hydroxide followed by conditioning with 0.2 M acetate buffer solution. The amount of zirconium leached out during the adsorption and regeneration cycles was negligibly small and the column can be used repeatedly.  相似文献   

12.
《分离科学与技术》2012,47(13):3545-3562
Abstract

A batch study showed that the presence of anions (sulfate, chloride, and nitrate) in solution did not affect the adsorption process of both As(V) and As(III) by iron oxide-coated A. niger biomass. It was found that the presence of Ca2+, Fe2+, and Mg2+ ions at a concentration of 200 mg/L in solution could increase the removal efficiency of As(V) by 86.5%, 95.4%, and 65.8%, respectively. Similarly, the presence of Ca2+, Fe2+, and Mg2+ ions at a concentration of 200 mg/L in solution could increase the removal efficiency of As(III) by 39.3%, 97%, and 8.4%, respectively. The batch adsorption-desorption study showed that the reactions between the arsenic species and the iron oxide-coated A. niger biomass were reversible. Desorption of As(V) and As(III) at neutral pH was approximately 15%. As(V) desorbed more than As(III) in acidic (pH 1.33) and alkaline (pH 12.56) solutions. At a pH of 1.33, 67% of the adsorbed As(V) desorbed, and the percentage of desorbed As(III) was only 47.1% in the same condition. At a solution pH of 12.56, 73.4% of the As(V), and 43.7% of As(III) desorbed. The thermodynamic study showed the spontaneous nature of the sorption of arsenic on IOCB. The high value of the heat of adsorption {ΔH ≈ ? 133 kJ/mol for As(V), and 88.9 k/mol for As(III)} indicated that the mechanism of arsenic sorption was chemisorption.  相似文献   

13.
Aluminum hydroxide‐poly[acrylamide‐co‐(acrylic acid)], AHAMAA, was synthesized with a redox initiator by solution polymerization in which the effects of reactant contents were optimized. The effects of pH, temperature, and initial dye concentration on Congo red reduction were investigated. A mixture of Congo red and direct blue 71, and the composite textile dye wastewater were investigated. Adsorptions of both dyes were more effective in the nonbuffered solution than those in the buffered solution, and Congo red adsorbed more than direct blue 71 at all pHs. The adsorption of Congo red increased with increasing temperature and its initial concentration. Both dyes obeyed the Freundlich adsorption isotherm. The maximum adsorptions in 100 mg dm?3 solution were 109 ± 0.5 mg g?1 and 62 ± 6.6 mg g?1 for Congo red and direct blue 71, respectively. At 150 mg dm?3 of the mixed Congo red and direct blue 71, the adsorption was 142 ± 2 mg g?1 by 643 ± 3 mg dm?3 AHAMAA. The 40 mg g?1 dyes of the textile effluent wastewater were adsorbed by 500 mg dm?3 AHAMAA. AHAMAA could decrease turbidity of the composite wastewater containing a mixture of reactive and direct dyes from 405 to 23 NTU. POLYM. ENG. SCI., 50:1535–1546, 2010. © 2010 Society of Plastics Engineers  相似文献   

14.
Carrier‐facilitated transport of mercury(II) against its concentration gradient from aqueous 0.1 mol dm?3 hydrochloric acid solution across a flat‐sheet supported liquid membrane (SLM) containing triisobutylphosphine sulfide (Cyanex 471X) as the mobile carrier in kerosene as diluent has been investigated. Dilute sodium thiocyanate solution (0.11 mol dm?3) was the most efficient stripping agent among several aqueous reagents tested. Various parameters such as stirring rate, concentration of HCl in the feed solution, concentration of NaSCN in the strippant, concentration of Cyanex 471X in the membrane, and contact time were investigated. Under optimum conditions the transport of Hg(II) across the liquid membrane is about 100% after 6 h. The carrier, Cyanex 471X, selectively and efficiently transported Hg(II) ions in the presence of other associated metal ions. The method has been demonstrated to recover selectively mercury from waste samples and mercurochrome solution. © 2002 Society of Chemical Industry  相似文献   

15.
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.  相似文献   

16.
《分离科学与技术》2012,47(10):1923-1931
Abstract

Iron(III) hydroxide-loaded marble (Fe-marble) was studied as an adsorbent to remove phenolic compounds from aqueous solution. The coordination of ligands with the central metal ion occurs through the phenolic oxygen. Sorption and break-through capacities were determined. The effects of pH and concentration were studied. Adsorption remains unaffected in the 2–6 pH range. Fe-marble exhibits good sorption capacities for phenolic compounds, and the adsorption data follow the Langmuir model as well as the Freundlich model. Some experiments were also performed with a view to recovery phenols and create in-situ regeneration of spent adsorbent column. The phenols adsorbed were quantitatively eluted with 1 M NaOH solution. The column can be used for 4–5 cycles consecutively.  相似文献   

17.
《分离科学与技术》2012,47(4):894-905
Abstract

A novel resin poly(sodium 4-styrene sulfonate-co-4-acryloyl morpholine) was synthesized through a radical solution polymerization in solution and studied as an adsorbent under uncompetitive and competitive conditions by batch and column equilibrium procedures for the following divalent metal ions Cd(II), Zn(II), Pb(II), and Hg(II), and trivalent Cr(III). For all metal ions, the adsorption was strongly influenced by the pH. The maximum retention capacity, 3.29 mmol of metal ion/g, was obtained for Zn(II) at pH 5 by batch equilibrium procedure. For both the batch and column procedures, the retention behavior was similar for Cd(II), Cr(III), Zn(II), and Pb(II).  相似文献   

18.
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  相似文献   

19.
A laboratory experiment has been made on the adsorption of the Cr3+ ion on freshly-precipitated titanium dioxide, in order to determine the effect of the concentrations of the Cr3+ and H+ ions in solution on the amount of the adsorbed chromium. The adsorption isotherms have been determined at 5 pH's (3.25 to 4.25). The adsorption at each pH is well shown by the Langmuir isotherm; it could be generalized by expressing the two parameters of the equation in function of the H+ proton activity: the maximum adsorption capacity may be represented by a second-degree polynomial (1/verbar;Hverbar;) and the adsorption constant by a power law. The general model proposed is the following: where X and C represent the adsorbed chromium concentration and the chromium concentration in solution, respectively. The aforesaid study has permitted to explain the coprecipitation of chromium (III) and titanium (IV) during the continuous neutralization of an industrial effluent containing both metals.  相似文献   

20.
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)64-) 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)64? on to protonated PVP by 75% over that at pH 7, a phenomenon explained by the formation of protonated ferrocyanide species, HFe(CN)63- and H2Fe(CN)62-. 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.  相似文献   

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