Synthesis and characterization of a new phase of zirconium phosphate for the separation of metal ions

The tetravalent metal acid (TMA) salt amorphous zirconium phosphate (ZP), an inorganic ion exchanger, has been synthesized by sol-gel method. The material has been characterized by elemental analysis (ICP-AES), thermal analysis (TGA, DSC), FT-IR and X-ray diffraction studies. Chemical resistivity of the material in various media-acids, bases and organic solvents has been assessed. The Na⁺ ion exchange capacity (IEC) and the effect of heating on the IEC have been determined, and showed the distribution and elution behavior of ZP towards several metal ions in different electrolyte media/concentrations. Based on the distribution studies, a few binary metal ion separations have been achieved.     

A new inorgano-organic ion exchanger; p-chlorophenol anchored to zirconium tungstate

Summary A new inorgano-organic ion exchanger, ZWpCP, prepared by anchoring p-chlorophenol to zirconium tungstate (ZW), exhibits good ion exchange capacity. Both ZW and ZWpCP were characterized by elemental analysis, thermal studies (t.g.a.) and spectral analysis (i.r. and FT-i.r.). The chemical stability of the products has been checked in acidic, basic and neutral organic media. The comparative ion exchange capacity and distribution behaviour of ZWpCP towards metal ions has been studied.     

Sorption of radionuclides on cerium(IV) molybdophosphate ion exchanger

Samples of a new inorganic ion exchanger cerium(IV) molybdophosphate have been prepared under varying conditions. Ion exchange capacity, I.R, thermogravimetry and sorption of radionuclides have been studied. Separations of Sr−Rb and Cd−Ag have been developed on column of this ion exchanger.     

Sodium titaniumsilicate as ion exchanger: synthesis, characterization and application in separation of 90Y from 90Sr

A new inorganic material, sodium titaniumsilicate has been synthesized, and characterized by physicochemical and spectroscopic tools. The thermal and radiation stability of the compound was checked by TGA technique and a ??-irradiating chamber with a total dose rate of 5?kGy/h. The compound is highly stable towards thermal, chemical and total radiation dose of 64?kGy. The study of the exchange capacity of the material towards different alkali and alkaline earth metal ions showed that the sorption capacities of the alkali metal ions were greater than those of alkaline earth metal ions. The crystalline state of this new inorganic material is very useful as an inorganic ion exchanger to have the carrier free short-lived ??-active daughter product ⁹⁰Y from the long-lived ⁹⁰Sr of the radioactive equilibrium mixture. The absorbed daughter was recovered by using 1.0% EDTA solutions at pH 7.0 as eluting agent. The features and trends in elution are encouraging to apply this material as an exchanger in radionuclide generator system.     

Calculation on ion exchange capacity for an ion exchanger using the potentiometric titration

We calculated the characteristics of a phosphoric cation exchanger and studied an accurately computable method for ion exchange capacity for a type of potentiometric titration curve. The ion exchanger was prepared by phosphorylation of a styrene‐divinylbenzene copolymer. The ion exchange capacity was 5.7 meq/g. The experimental pK values versus χ in a phosphoric cation exchanger can explain a linear equation. The ΔpK values were obtained from the slope of a linear equation. The ΔpK values were the differences of pK values between the apparent equilibrium constant at complete and zeroth neutralization of the ion exchanger. The experimental pK values at χ = 0.5 (χ:degree of neutralization of ion exchanger) showed good agreement with the theoretical data. When it was titrated with NaOH and Ba(OH)₂ solutions, a good agreement between experimental and theoretical pK values for various χ was found in all potentiometric titration curves. The potentiometric titration curve near the inflection point in the case of divalent ions was changed more sharply than that for monovalent ions. The plot of ∂pH/∂g versus g (number of moles of alkali to 1 g of ion exchanger) was fitted to the Lorenzian distribution, from which ion exchange capacity was accurately evaluated. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 3181–3188, 2000     

从高放废液中提取铯的新型环境材料

从高放废液（ HLLW）碱性澄清液中去除铯 137Cs的技术已经有几十年的历史 [1],但仍有较大的弊端．如果能直接从高放废液（ H＋浓度为 3 mol· L－ 1左右）中去除铯 137Cs,则可以避免大量碱的中和过程．多年来,各国科学家们致力于这方面的研究并取得了一定的进展 [1－ 5].　　无机离子交换技术,凭其所特有的优势已经成为核废物处理中较为经济和适宜的手段之一 [6－ 9].聚磷杂多酸盐是一类高性能离子交换剂,近年来发展很快 [10,11].本文合成了六种焦磷杂多酸盐（下文以 ABPP表示,其中 A代表金属离子, B代表杂酸根离子, PP代表…     

Synthesis,characterization and adsorption behaviour of TX-100 based Sn(IV) phosphate,a new hybrid ion exchanger

A new hybrid ion exchanger, Triton X-100 based tin(IV) phosphate (TX-100SnP) has been synthesized and characterized by ion exchange and physico-chemical methods such as ion exchange capacity, elution and concentration behaviour, IR, X-ray, TG/DTA and elemental analysis. Its adsorption behaviour has also been studied for some alkaline earths and heavy metal ions in different acidic media. It has been found generally more selective for metal ions as compared to tin(IV) phosphate prepared earlier. For Pb(II), Hg(II) and Fe(III) its selectivity has been found to be exceptionally good. On this basis, some binary separations have been performed involving these metal ions. Thermal studies show a high thermal stability of the material. It retains 54.54% of its i.e.c. at 200°C and 27.27% at 300°C.     

Equilibrium properties of charged spherical colloidal particles suspended in aqueous electrolytes: finite ion size and effective ion permittivity effects

The adsorption behaviour and mechanism of As(III) and Se(IV) oxyanion uptake using a mixed inorganic adsorbent were studied. The novel adsorbent, based on Fe(III)-Mn(III) hydrous oxides and manganese(II) carbonate, was synthesised using a hydrothermal precipitation approach in the presence of urea. The inorganic ion exchanger exhibited a high selectivity and adsorptive capacity towards As(III) (up to 47.6 mg/g) and Se(IV) (up to 29.0 mg/g), even at low equilibrium concentration. Although pH effects were typical for anionic species (i.e., the adsorption decreased upon pH increase), Se(IV) was more sensitive to pH changes than As(III). The rates of adsorption of both oxyanions were high. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) studies showed that the ion exchange adsorption of both anions took place via OH(-) groups, mainly from Fe(III) but also Mn(III) hydrous oxides. MnCO(3) did not contribute directly to As(III) and Se(IV) removal. A higher adsorptive capacity of the developed material towards As(III) was partly due to partial As(III) oxidation during adsorption.     

Electrical conductivity and cation exchange kinetic studies on poly-o-toluidine Th(IV) phosphate nano-composite cation exchange material

An advanced organic–inorganic cation exchange material poly-o-toluidine Th(IV) phosphate nano-composite was synthesized by a modified sol–gel technique by incorporating Th(IV) phosphate precipitate with the matrix of poly-o-toluidine. The material showed good ion-exchange behavior and used successfully in separation of metal ions. The conductivity of the composite was found within the range of 10⁻² to 10⁻³ S/cm; measured by 4-in-line-probe dc electrical conductivity measuring technique. The conductivity is at the border of metallic and semiconductor region. Ion-exchange kinetics for few divalent metal ions was evaluated by particle diffusion-controlled ion-exchange phenomenon at four different temperatures. The particle diffusion mechanism is confirmed by the linear τ (dimensionless time parameter) versus t (time) plots. The exchange processes thus controlled by the diffusion within the exchanger particle for the systems studies herein. Some physical parameters like self-diffusion coefficient (D₀)_, energy of activation (E_a) and entropy of activation (ΔS⁰) have been evaluated under conditions favoring a particle diffusion-controlled mechanism.     

A polar-copolymerized method to prepare silica-based anion exchanger for ion chromatography

A novel silica-based strong anion exchanger was developed for ion chromatography by copolymerizing methyltrichlorosilane and 3-chloropropyltrichlorosilane. The method allows the column capacity to be easy control simply by adjusting the ratio of silanes. The unwanted residual silanol groups onto the surface of silica gel could also be greatly reduced by this strategy. The effective column capacity of the column used was measured to be 50.8 μequiv/column (2.03 μequiv/cm). The exchanger was characterized by solid state CP/MAS ¹³C NMR and elemental analysis and its separation performance was evaluated for the separation of common inorganic anions. The results showed that the column had good separation efficiency (e.g. the plate number of nitrite is 80,000/m) and the separation mechanism was observed to be dominantly governed by ion exchange mechanism. The utility of the column was demonstrated for the determination of nitrite and nitrate in saliva sample.     

Zirconium vanadophosphate as an inorganic ion exchanger

Zirconium vanadophosphate was characterized as a stable inorganic ion exchager. The ion-exchange capacity was measured as 1.75 meq. H⁺ g^?1 at room temperature and it is stable up to 300°C. The exchanger is selective for devalent cations and the order of sorption of cations was found to be M²⁺ > M⁺ > M³⁺ M⁴⁺. Separations of Co²⁺?Ni²⁺, Cu²⁺?Hg²⁺ and Cr(VI)?Cr³⁺ were achieved on a column containing the ion exchanger. Copper could be separated from other base metals in geochemical samples. Differential thermal analysis showed an endothermic peak in the range of 65–420°C due to the dehydration of the ion exchanger with a low activation energy of 7.79 kcal mol^?1, which follows first-order kinetics. The ion exchanger did not show any further decomposition up to 1000°C. Infrared studies confirmed the presence of

groups which act as exchange sites for the cations. X-ray diffraction studies revealed that the compound is crystalline, with a crystal structure resembling that of the mineral muscovite.     

基于季铵化烯丙基缩水甘油醚改性的阴离子交换固定相的制备北大核心CSCD

制备了一种季铵化烯丙基缩水甘油醚(allyl glycidyl ether,AGE)改性聚合物基质的阴离子固定相应用于离子色谱系统。它是利用AGE与水解的聚甲基丙烯酸缩水甘油酯-二乙烯基苯poly(glycidylmethacrylate-divinylbenzene,GMA-DVB)微球表面残留双键通过表面自由基共聚,再通过N,N-二甲基乙醇胺(一种叔胺)进行开环反应制备得到的。通过考察有机叔胺类型、微球水解、单体和引发剂用量、反应温度和时间对7种阴离子分离性能的影响,优化了制备条件。采用扫描电镜、元素分析对所得阴离子固定相进行了表征。结果表明,采用预先水解的GMA-DVB微球(水解过程中微球表面丰富的环氧基团转化为羟基)相对于直接采用GMA-DVB微球有助于降低固定相的交换容量和微球自身的非离子吸附作用;通过淋洗液浓度和目标离子保留因子的拟合结果证实了该固定相保留机理为典型的离子交换作用。使用碳酸根淋洗液,在优化的色谱条件下,该固定相可在13 min内实现常见7种无机阴离子的基线分离,并表现出较高的柱效(Cl-理论塔板数为49000块/m)。该色谱柱实用性通过分析自来水实际样品进行了验证。     

Zirconium arsenophosphate as an ion exchanger

Zirconium arsenophosphate (ZAP) a new inorganic ion exchanger has been synthesized under varying conditions of precipitation. The material possesses good chemical and thermal stabilities and regeneration power. It shows no breakdown on irradiation with a gamma dose of ～10⁹ rad. ZAP shows high affinity for univalent ions like Rb⁺, Ag⁺ and Tl⁺. The Kd-values have been determined for a number of metal ions from acid media. The stoichiometry of metal ion uptake was checked using almost carrier-free radiotracers. Sixteen binary/ternary separations of metal ions are reported on a ZAP column.     

球形复合无机离子交换剂水合氧化钛-硅钛酸钠的制备及性能研究

用溶胶-凝胶法制备了球形除铯复合无机离子交换剂水合氧化钛-硅钛酸钠(HTO-NaTS),研究了在酸性条件下其对铯离子的交换性能,并对其结构、稳定性作了初步研究.结果表明,此种球形交换剂在强酸性条件下机械稳定性好,适合装柱,在1mol/L HNO3水溶液中,对铯离子具有较高的交换容量.     

Pyridine based thorium(IV) phosphate hybrid fibrous ion exchanger

Pyridine based thorium(IV) phosphate (PyThP) has been synthesized by drop-wise addition of the thorium(IV) nitrate with constant stirring into a mixture of pyridine and phosphoric acid. This material has been characterized using X-ray, IR spectra, TG, DTG and SEM studies in addition to its ion exchange capacity, elution and pH titrations. The material has been found amorphous and fibrous in nature on the basis of X-ray diffraction and SEM studies. TG has revealed the changes incurred in the material on thermal treatment and IR spectral studies have shown the presence of various groups in its structure.     

Separation and Recovery of Some Metal Ions Using Pan Sorbed Zinc Silicate as Chelating Ion Exchanger

Abstract

A new inorganic ion exchanger zinc silicate has been synthesized. Its properties such as ion exchange capacity, heat effect and stability etc. have been studied. Sorption of PAN over zinc silicate formed a chelate ion exchanger which showed greater selectivity for some metal ions especially for Cu²⁺, Ni²⁺, Co²⁺, Fe³⁺, Ag⁺, Ag³⁺ and Pt⁴⁺. Selectivity has been determined on the basis of distribution coefficients of these metal ions. Separations of Pt(IV) from Fe(III), Au(III) from Fe(III), Ag(I) from Cu(II) and Au(III) from Cu(II) have been reported. The recovery of Pt(IV) and Au(III) from dilute solutions has also been studied.     

Thermal characterization of hydrous tungsten oxides and their behavior as ion exchanger

The preparation, and thermal characterization and ion exchanger behavior of hydrous tungsten oxides obtained from purified tungsten trioxide, by processing of a Brazilian scheelite ore were described. By an alkaline fusion of tungsten trioxide with an excess of sodium carbonate at 900°C an intermediate tungstate product is obtained. Acid lixiviation of the tungstate intermediary in different experimental conditions produces two different hydrous tungsten oxides I and II respectively. A third material was produced by thermal treatment of II, yielding the material IIA, a monohydrate species. The materials prepared were characterized by TG/DTG, X-ray diffractometry and by surface area measurements. Their ion exchange behavior was studied too, using Na⁺ and K⁺ ions as the exchanged species. The inorganic exchanger materials were partially regenerated and may be used consecutively. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis and characterization of zirconium(IV) iodovanadate and its use as electron exchanger

Samples of zirconium(IV) iodovanadate have been synthesized under varying mixing ratios by adding a mixture of aqueous solution of 0.1 M potassium iodate and 0.1 M sodium metavanadate to aqueous solution of 0.1 M zirconium oxychloride at pH 1. The ion exchange capacity of the material for Na⁺ ion was found to be 2.20 meq g⁻¹ of dry exchanger. The material has been characterized on the basis of chemical composition, FTIR and TGA. The chemical stability of the product has been checked in neutral, acidic and basic media. The product has been used as electron exchanger. The oxidation of Fe(II), Sn(II), ascorbic acid and thioglycolic acid was achieved by batch-equilibrium technique successfully. The maximum redox capacity of the exchanger has been found to be 4.20 meq g⁻¹ of exchanger by column process.     

Synthesis of Quaternized poly(4-Vinyl Pyridine) and the Study of its Ion Exchange Property

Lightly cross-linked poly(4-vinyl pyridine) has been synthesized from 4-vinyl pyridine and a small amount of ethylene glycol dimethacrylate (EGDMA) in aqueous medium through micelle technique. The polymer is then quaternized with 1,4-dibromobutane to develop an anion exchange resin with high selectivity and ion exchange capacity at a wide range of pH and temperature. The material exhibits high ion exchange capacity and reverse anion selectivity order compared to commercially available anion exchanger. A method has been designed to separate chromate and sulfate using the synthesized material.     

STUDIES ON SYNTHESIS AND CHARACTER OF INORGANIC ION EXCHANGER TITANIUM PHOSPHATE-AMMONIUM TUNGSTOPHOSPHATE

Since1980s,Phosphates--AmmoniumMolybdophosphate[1--5]ascomplexinorganicionexchangershavebeendeeplystudiedinproducingandcharacterfortheseparationofradio--nuclidesandtreatmentofradioactivewastewater.Whosedevelopmentprovideanewthoughtforthesynthesisandcreationofnewtypeofinorganicionexchangers.Complexinorganicionexchangerssurmounteddefectsofrelativeuncomplexedmaterialswhileinpracticalapplication,andexhibitedtobemuchbetteroverhydrauliccharacter.elutionanduptaking.AmmoniumTungstophosphate(AWP)asa…