Adsorption behaviors and mechanisms of gold recovery from thiosulfate solution by ion exchange resin

The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold showed that gel Amberlite IRA-400 resin with Type Ⅰ quaternary ammonium functional group had better adsorption performance.The increases of resin dosage,ammonia concentration and solution pH were favorable to gold adsorption,whereas the rises of cupric and thiosulfate concentrations were disadvantageous to gold loading.Microscopic characterization results indicated that gold was adsorbed in the form of [Au(S_(2)O_(3))_(2)]^(3–) complex anion by exchanging with the counter ion Cl^(–) in the functional group of the resin.Density functional theory calculation result manifested that gold adsorption was mainly depended on the hydrogen bond and van der Waals force generated between O atom in [Au(S_(2)O_(3))_(2)]^(3–) and H atom in the quaternary ammonium functional group of the resin.

ADSORPTION OF 2,4-DICHLOROPHENOL IN AQUEOUS SOLUTION ONTO ADSORPTION RESIN MODIFIED BY N-ACETYLANILINE

A hypercrosslinked adsorption resin （ZH-05） modified by N-acetylaniline in the post crosslinking process was prepared. The adsorption properties of ZH-05 toward 2,4-dichlorophenol in comparison with granular activated carbon （GAC） and Amberlite XAD-4 were observed. The present study mainly focuses on the static equilibrium adsorption behaviors, desorption profiles and the proof of chemisorption. The results show that the Langmuir equation can give a perfect fitting to experimental data, and high temperature was favorable for adsorption of 2,4-dichlorophenol on ZH-05. A related equation was used to correlate the amount of chemisorption and the suppositionai chemisorption equilibrium concentration of adsorbate in aqueous solution. The adsorption capacities from different ranges of temperature and the static desorption experiment both reveal the same conclusion, i.e., the adsorption of 2,4-dichlorophenol from water on ZH-05 is a coexistent process of physical adsorption and chemical transition as on GAC.

Blood hemoperfusion with resin adsorption combined continuous veno-venous hemofiltration for patients with multiple organ dysfunction syndrome

BACKGROUND:Blood hemoperfusion with resin adsorption can clean larger molecules that exceed the molecular weight cutoff of combined continuous veno-venous hemofiltration(CWH).Hence blood hemoperfusion with resin adsorption combined CWH(HP+CWH) has higher ability of mediator clearance,and can improve clinical outcomes in theory.This study aimed to investigate the effect of blood hemoperfusion with resin adsorption combined continuous veno-venous hemofiltration(HP+CWH) on plasm cytokines like TNF-α,IL-1β,IL-6,cellular immunity and prognosis in patients with multiple organ dysfunction syndrome(MODS).METHODS:This was a prospective,randomized clinical trial.A total of 30 patients who had been diagnosed with MODS were enrolled in this study.Patients were randomly allocated to routine treatment+HP+CWH group(treatment group) and routine treatment+only CWH group(control group).In the treatment group,patients received blood hemoperfusion with resin adsorption for 2hours,and then received CWH for 10 hours every day.In the control group,patients received CWH for 12 hours only every day.The patients in the two groups received blood purification therapy for three days.The plasma of patients in the treatment group was obtained at 0,2,12,24,26,36,48,50,60 hours,5th day,7th day and 10 th day,respectively.The plasma of patients in the control group was obtained at 0,12,24,36,48,60 hours,5th day,7th day and 10 th day,respectively.APACHE Ⅱscore,T-lymphocytes subpopulations,blood lactate acid concentration,heart rate,breathing rate,and oxygenation index were observed.RESULTS:Plasma cytokines like TNF-α,IL-1β,IL-6 decreased markedly after HP(P<0.01);T-lymphocytes subpopulations CD3+,CD4+,CD8+,CD4+/CD8+ increased after HP+CWH or only CWH.The plasma concentrations of TNF-α,IL-1β and IL-6 in the two groups were not markedly different at 12,36,and 50 hours.But on the 5th day,the plasma concentrations of TNF-α,IL-1β and IL-6 in the treatment group were lower than those in the control group(P<0.05).On the 28 th day,5patients died in the treatment group,and 6 patients in the control group.CONCLUSIONS:Both HP+CWH and CWH can clean plasma cytokines like TNF-α,IL-1β,and IL-6,and improve cellular immunity and clinical symptoms and signs of patients.Compared with only CWH,the plasma concentrations of TNF-α,IL-1β and IL-6 were lower on the 5th day,and patients have an increased survival rate on the 28 day in the HP+CWH group.

Separation and Purification of Total Phloroglucinols in Dryopteris crassirhizoma with DM-130 Macroporous Adsorption Resin

To improve the purity of the total phloroglucinols from Dryopteris crassirhizoma extracts, the separation and purification conditions of the total phloroglucinols from Dryopteris crassirhizoma were studied with DM-130 macroporous adsorption resin in this study. Adsorption rate, elution rate and purity of the total phloroglucinols were used as indexes to investigate the adsorption and desorption capacity of the total phloroglucinols with DM-130 macroporous adsorption resin. Through the study, the optimum sample concentration of the total phloroglucinols and maximum sample volume were 1.5 mg·mL^-1 and 7 BV （210 mL）, respectively. The optimum desorption conditions were achieved by using 80% ethanol as desorption solvent at elution flow rate of 1.0 mL·min^-1. The result showed DM-130 macroporous adsorption resin performed effective adsorption and desorption. After purification, the purity of the total phloroglucinols increased by 11.5-fold.

Adsorption Behaviors and Mechanism of Macroporous PhosphonicAcid Resin for Gadolinium

The adsorption behaviors and mechanism of a novel chelate resin, macroporous phosphonic acid resin(PAR)for Gd(Ⅲ)were investigated. The statically and dynamically saturated adsorption capacity is respectively 308 mg·g^(-1)resin and 296 mg·g^(-1)resin at 298 K in HAc-NaAc medium at pH 5.6. Gd(Ⅲ)adsorbed on PAR can be reductively eluted by 0.5～5.0 mol·L^(-1) HCl used as eluant and the elution percentage is up to 94.7% in 1.0 mol·L^(-1) HCl. The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k_(298)=3.96×10^(-5) s^(-1). The adsorption behavior of PAR for Gd(Ⅲ) conforms to the Freundlich isotherm. The thermodynamic adsorption parameter, enthalpy change △H of PAR for Gd(Ⅲ)is 22.6kJ·mol^(-1). The apparent adsorption activation energy(Ea)of PAR for Gd(Ⅲ)is 5.0 kJ·mol^(-1). The molar coordination ratio of the functional group of PAR to Gd(Ⅲ)is about 3∶1. The adsorption mechanism of PAR for Gd(Ⅲ)was examined by using chemical method and IR spectrometry.

PURIFICATION OF FLAVONES OF GINKGO LEAVES BY ADSORPTION HZ-841 RESIN

The purification process of total flavones of ginkgo leaves by resin HZ-841 from ethanol extract was studied. First, the total flavone was extracted from the defatted powder of ginkgo L. biloba leaves. Effects of solvents and operation conditions were examined to get a relative high yield and purity in this step. The crude extract was further purified by resin HZ-841. Both adsorption and elution process were studied to obtain an optimized conditions, i.e., pH, flow rate, concentration. A yellow powder was obtained, of which 37.3% was flavones, obviously higher than the basic international standard of 24%.

Preparation of Macroporous Poly (vinyl alcohol-co-triallyl isocyanurate) Beads Bearing Aminocarboxylic Acid as Functional Groups by Suspension Polymerization

Macroporous poly (vinyl acetate-co-triallyl isocyanurate) beads were prepared with suspension polymerization method. The copolymer beads were then transformed into poly (vinyl alcohol-co-triallyl isocyanurate) by ester exchange reaction. Aminocarboxylic acids were immobilized on the copolymer beads by the esterification of hydroxyl groups with diethyl-lenetriaminepentaacetic bisanhydride. The weak acid exchange capacities, specific surface areas and mean pore diameters of the resultant resin beads were measured.

Adsorption and Desorption of Phenol on XDA-1 Macroreticular Resin

The adsorption properties of phenol on XDA-1 resin were studied by chemical analysis and IR spectrometry.The statically saturated adsorption capacity,dynamic saturated adsorption capacity,apparent activation energy,thermodynamic parameters,and adsorption rate constants were measured at different temperatures.As a result,adsorption of phenol on the resin obeys the Freundlich formula.And phenol was recovered quantitatively when ethanol,acetone or 1.0 mol/L sodium hydroxide were used to desorb it from the column.

ISOLATION AND PURIFICATION OF ALKALOIDS FROM PLUMULA NELUMBINIS BY DOUBLE-COLUMN ADSORPTION CHROMOTOGRAPHY

The performance of adsorption and separation for liensinine, isoliensinine and neferine was studied by double-column adsorption chromatography using macroporous adsorption and cation exchange resins. The alkaloid extract with 49.2% total contents by mass representing 10.6% liensinine, 10.6% isoliensinine and 28.0% neferine respectively was prepared by D72 cation exchange resins, in which most of the impurities were water-soluble alkaloids. Furthermore,the alkaloid extract with 82.6% total contents by mass containing 33.1%, 15.0% and 34.5% of the three adsorbates respectively was prepared by double-column adsorption chromatography using AKS-W macroporous adsorption and D72 cation exchange resins. As a result, the content of single and total alkaloids has been greatly increased by the double-column adsorption chromatography.

THE SEPARATION,PURIFICATION AND DECOLORIZATION OF NEW ANTIBIOTICS-MILUPEINAN USING ADSORPTION RESIN

Adsorption resin AAS was used for the separation and purification of milupeinan (M-13) from its mother liquor. The good adsorption property of AAS adsorption resin was found for milupeinan (M-13) compared with the Diaion CHP 20p. When acetone and water (2:1 in volume) were used as desorption reagents, it was found that 3 times of bed volume of the desorption reagents would make the AAS resin which was saturately adsorpted M-13 desorption completely. Also a macroporous anion exchange resin (Poly-4-vinylpyridine type) D-280 was used for the decolourization from M-13 solution. Good results was given when the sv=1~2.

STUDY ON THE DECOLORIZATION OF D-RIBOSE ZYMOTIC FLUID BY RESIN ADSORPTION

In this paper, effects on of six type of resins the decolorization of D-ribosezymotic fluid have been studied for the fist time. The results show that resinNKA-II has the best effect. the decolorization rate of D-ribose zymotic fluid is91% at velocity of 1.0BV/hr and 25℃, the adsorption capacity can reach up to5.7BV. The effects of adsorption conditions as well as conditions of resinregeneration on the resin decolorization capability were also studied.

Research on the Separation and Purification of Cordyceps sinensis polysaccharides by Macro porous Adsorption Resin

In this study, the separation and purification of Cordyceps sinensis polysaccharides by AB-8 and D-280 macro porous ad- sorption resin were researched, the adsorption characters when AB-8 macro porous adsorption resin processed Cordyceps sinensis leachate were determined, and the eluent were bleaching treated by D-280 macro porous adsorption resin. The results showed that the concentration of 2.0mg/mL, pH = 6 at a flow rate of 0.8mL/min. The yielding amount of polysaccharides is 246.4mg, and after decolouring treatment, the final yield is 207.1 mg.

Alternative technology for the recovery of butyl acetate with low concentration:high capacity adsorbent and high efficiency adsorption

Industrial pharmaceutical wastewater usually contains butyl acetate(BA)with a concentration of 1 wt%-7 wt%,and the traditional method for BA recovery is distillation with high energy consumption.Adsorption method is developed to recover BA with low concentration for the high efficiency and low energy consumption.Medium polar polyacrylate resins with macroporous structure of 233.1 nm and average particle size of about 526.5μm are successfully synthesized by suspension polymerization and used for the BA adsorption and desorption.The maximum adsorption capacity reaches 171.1 mg g^(-1)with relative standard deviation(RSD)value of 0.2%,which is more than twice the results in the literature.The BA desorption rate is 97.0%at 100℃with RSD value of 0.4%,and the resins are beneficial to the reuse in the adsorption-desorption cycle.The adsorption thermodynamics and kinetics are investigated,and the BA adsorption is a spontaneous and endothermic process with the increase of disorder degree.This process is mainly contributed by physical absorption and agree well with Freundlich model and pseudo-first-order adsorption kinetic model.The adsorption method avoids boiling a large amount of wastewater and hopefully provides a novel alternative technology for the BA recovery.

Adsorption of three pharmaceuticals on two magnetic ion-exchange resins

The presence of pharmaceuticals in aquatic environments poses potential risks to the ecology and human health. This study investigated the removal of three widely detected and abundant pharmaceuticals, namely, ibuprofen（IBU）, diclofenac（DC）, and sulfadiazine（SDZ）, by two magnetic ion-exchange resins. The adsorption kinetics of the three adsorbates onto both resins was relatively fast and followed pseudo-second-order kinetics. Despite the different pore structures of the two resins, similar adsorption patterns of DC and SDZ were observed, implying the existence of an ion-exchange mechanism. IBU demonstrated a combination of interactions during the adsorption process. These interactions were dependent on the specific surface area and functional groups of the resin. The adsorption isotherm fittings verified the differences in the behavior of the three pharmaceuticals on the two magnetic ion-exchange resins. The presence of Cl-and SO2-4suppressed the adsorption amount, but with different inhibition levels for different adsorbates. This work facilitates the understanding of the adsorption behavior and mechanism of pharmaceuticals on magnetic ion-exchange resins.The results will expand the application of magnetic ion-exchange resins to the removal of pharmaceuticals in waters.

Adsorption behavior of benzenesulfonic acid by novel weakly basic anion exchange resins

Two novel weakly basic anion exchange resins（SZ-1 and SZ-2） were prepared via the reaction of macroporous chloromethylated polystyrene-divinylbenzene（Cl-PS-DVB） beads with dicyclohexylamine and piperidine, respectively. The physicochemical structures of the resulting resins were characterized using Fourier Transform Infrared Spectroscopy and pore size distribution analysis. The adsorption behavior of SZ-1 and SZ-2 for benzenesulfonic acid（BA） was evaluated, and the common commercial weakly basic anion exchanger D301 was also employed for comparison purpose. Adsorption isotherms and influence of solution p H, temperature and coexisting competitive inorganic salts（Na2SO4and Na Cl） on adsorption behavior were investigated and the optimum desorption agent was obtained.Adsorption isotherms of BA were found to be well represented by the Langmuir model.Thermodynamic parameters involving ΔH, ΔG and ΔS were also calculated and the results indicate that adsorption is an exothermic and spontaneous process. Enhanced selectivity of BA sorption over sulfate on the two novel resins was observed by comparison with the commercial anion exchanger D301. The fact that the tested resins loaded with BA can be efficiently regenerated by Na Cl solution indicates the reversible sorption process. From a mechanistic viewpoint, this observation clearly suggests that electrostatic interaction is the predominant adsorption mechanism. Furthermore, results of column tests show that SZ-1possesses a better adsorption property than D301, which reinforces the feasibility of SZ-1for potential industrial application.

Separation of gibberellic acid (GA3) by macroporous adsorption resins

The adsorption effects of several macroporousadsorption resins for gibberellic acid (GA3) were investigated.The dynamic adsorption capacity is 58.38 mg/g drybeads for resin R4 and 96.46 mg/g dry beads for resin R5which is consistent with the surface area. Aqueous methanol(50%, V/V) is a good eluent and the yield of GA3 isabove 95%. The concentration of GA3 could increase fivefoldafter an adsorption-elution cycle and this is importantwhen considering further crystallization of GA3 in anindustrial process.

Preparation and decolorization of sapindus mukurossi extract and its application in sebum-control shampoos

Background:Sapindus mukurossi extract(SME)is a kind of natural surface active ingredient with potential applications in cleansing products.However,the polyphenols and pigments contained in the extract may cause color browning of the products during storage especially at elevated temperatures,affecting its high level addition in the products.Objective:To explore a decolorization process suitable for industrialization realize the high level addition of SME and explore the potential of SME in the field of controlling sebum esters.Materials and Methods:SME was prepared by adsorbing polyphenols on the D301 resin and oxidation decoloring oxidation.Investigated its sebum-control efficacy by SZ95 model and clinical study.Results:The results demonstrate that the D301 resin displays the best adsorption selectivity for polyphenols in SME,and the polyphenol adsorption ratio of D301 resin(5 wt%)can reach 83.6%;The optimal decolorization conditions are pH=7.8,temperature 73℃and decolorization time 5.7 h when H2O2 content is 6%,The prepared SME shows no obvious changes in color and retain stable during the high temperature(50℃)test period of 28 days.4μg/mL of SME decreases the lipid synthesis of SZ95 cells by 24.8%.The clinic efficacy of the shampoo containing 10%SME(by dry extract weigh)is further evaluated.No significant changes in the skin moisture content and transepidermal water loss(TEWL)are observed within four weeks after using the product,while the scalp sebum level is significantly reduced.Conclusion:In this study,we prepared a light-colored,highly stable SME,enabled its high-level addition in cleansing and care products and found its sebum-control efficacy.

Extractant(2,3-dimethylbutyl)(2,4,40-trimethylpentyl) phosphinic acid(INET-3) impregnated onto XAD-16 and its extraction and separation performance for heavy rare earths from chloride media

（2,3-Dimethylbutyl）（2,4,40-trimethylpentyl）phosphinic acid（INET-3） was impregnated onto dry macroporous resins XAD-16 and pretreated XAD-16 with ethyl alcohol and HCl（Pre-XAD-16） to prepare the solvent impregnated resins SIRs-INET-3/XAD-16 and SIRs-INET-3/Pre-XAD-16. The molecular weight distribution of the low molecular weight（LMW） polymers washed off by ethyl alcohol during XAD-16 pretreatment was determined by gel permeation chromatography（GPC）. The macroporous resins（XAD-16 ＆ Pre-XAD-16）, the corresponding solvent impregnated resins（SIRs-INET-3/XAD-16 ＆SIRs-INET-3/Pre-XAD-16） and the PVA coated SIRs-INET-3/Pre-XAD-16 with boric acid as cross-linking agent were characterized by FT-IR, SEM-EDS and TGA. The effects of XAD-16 pretreatment and PVA coating technology on RE（III） adsorption equilibrium time, INET-3 losses during extraction and adsorption capacity were investigated. The adsorption kinetics, selectivity and stripping behaviors of SIRs-INET-3/XAD-16 were further studied. The washed off LMW polymers had the Mn of 36,656, Mw of 40,310 and polydispersity coefficient of 1.10. The SIRs-INET-3/XAD-16 had shorter equilibrium time,less INET-3 loss and more Tm（III） adsorption capacity than the SIRs-INET-3/Pre-XAD-16. The PVA coated SIRs-INET-3/Pre-XAD-16 had less INET-3 loss and more Tm（III） adsorption capacity but longer equilibrium time than the uncoated SIRs-INET-3/Pre-XAD-16. The adsorption of RE（III） on the SIRsINET-3/XAD-16 followed the pseudo-second-order kinetic model. The Tm（III） accumulative adsorption amounts onto SIRs-INET-3/XAD-16 after eight extraction stages was 23.6 mg/g. The separation factors of adjacent heavy RE（III） β（Er/Ho）, β（Tm/Er）, β（Yb/Tm） and β（Lu/Yb） values were 1.76, 2.59, 2.56 and 1.19,respectively. The adsorbed Lu（III） onto the SIRs-INET-3/XAD-16 can be stripped completely by 1.0 mol/L H2SO4.

Preparation of new hyper cross-linked chelating resin for adsorption of Cu^(2+) and Ni^(2+) from water

The new hyper cross-linked chelating resin NDWJN2 modified with carboxyl groups was prepared for removal of Cu^（2＋） and Ni^（2＋） from water.NDWJN2 was characterized using BET,SEM and FT-IR spectroscopy.Comparing with commercial resins D113 and IRC84,NDWJN2 could remove Cu^（2＋） and Ni^（2＋） from water more effectively.Langmuir model could fit adsorption isotherms well.

Optimization of polyacrylonitrile-cysteine resin synthesis and its selective removal of Cu(Ⅱ) in aqueous solutions

Polyacrylonitrile beads（PAN） cysteine（CS） was synthesized from polyacrylonitrile beads（PAN） and cysteine（CS）.The content of the functional group and the percentage conversion of the functional group of PAN-CS prepared under the optimum condition using response surface methodology（RSM） for the first attempt were 3.22 mmol/g and 35.78%.The structure was characterized by ET-IR and elemental analysis.The adsorption properties of the resin for Cu（Ⅱ） were investigated by batch and column experiments.Batch adsorption results suggested that PAN-CS had higher adsorption capability for Cu（Ⅱ）than other metal ions and maximum saturated adsorption capacity was 184.7 mg/g.The resin and its metal complexes were studied by FT-IR.Furthermore,the resin can be eluted easily using 1 mol/L HC1.PAN-CS can provide a potential application for selective removal of copper from waste solution.