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1.
Hidemitsu Aoki Kazuki Miyano Daisaku Yano Koji Yamanaka Takashi Sugino 《Electrochimica acta》2008,53(22):6657-6661
A biological and chemical sensor with rapid response at the microlevel is required for health and environmental monitoring. To develop a high-performance sensor, we use a porous monolith-type ion exchanger having three-dimensional acceptors to sense chemical substances. This porous monolith-type ion exchanger has an open-cellular structure with 5-50-μm diameter pores. The concentration of amino acids in the solution can be detected by measuring the impedance of the monolith-type ion exchanger. The novel ion exchanger has a high-exchange rate and high-electrical conductivity compared with that of the conventional ion-exchange resins. It is found that the impedance of the porous ion exchanger varies widely, depending on the amino acids such as glycine, asparatic acid, lysine, and phenylalanine. The impedance of anion exchanger had the highest value for phenylalanine with a benzene ring. OH-ion conduction is suppressed possibly due to the phenylalanine molecules stabilized by the hydrophobic interaction with the anion exchanger. In addition, we succeeded in sensing amino acid ions with concentration as low as 10−7 mol. The porous ion exchanger has the potential of a high-performance device for biological and chemical sensing. 相似文献
2.
The aim of this article is to observe anomalous behaviour of strong acid cation (SAC) exchanger in VVER and PWR power plants. This ion exchanger is a part of primary water coolant purification system and shows a non-standard operation in the end of the fuel cycle during high-performance effect. This behaviour consists in process’ changes of potassium cation capture from boric acid solution, which is a major chemical of primary cooling water. The experiments were conducted under laboratory conditions on ion exchanger type DOWEX HCR-S NG and the samples with different concentrations of analytes (K+, NH4+, Li+, H3BO3) were measured. The results confirmed the anomalous behaviour of ion exchanger during high-performance effect when the potassium ions are captured on SAC due to its size and the lack of boric acid in water coolant. Therefore, the potassium hydroxide must be dosed into the primary water to control the content of alkali metals. 相似文献
3.
Polypyrrole Th(IV) phosphate, an electrically conducting ‘organic‐inorganic’ cation‐exchange composite material was prepared by the incorporation of an electrically conducting polymer, i.e., polypyrrole, into the matrix of a fibrous type inorganic cation‐exchanger thorium(IV) phosphate. The composite cation‐exchanger has been of interest because of its good ion‐exchange capacity, higher chemical and thermal stability, and high selectivity for heavy metal ions. The temperature dependence of electrical conductivity of this composite system with increasing temperatures was measured on compressed pellets by using four‐in‐line‐probe dc electrical conductivity measuring instrument. The conductivity values lie in the semiconducting region, i.e., in the order of 10?6 to 10?4 S cm?1 that follow the Arrhenius equation. Nernst–Plank equation has been applied to determine some kinetic parameters such as self‐diffusion coefficient (D0), energy of activation (Ea), and entropy of activation (ΔS*) for Mg(II), Ca(II), Sr(II), Ba(II), Ni(II), Cu(II), Mn(II), and Zn(II) exchange with H+ at different temperatures on this composite material. These results are useful for predicting the ion‐exchange process occurring on the surface of this cation‐exchanger. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
4.
Joonwon Bae Gyo Eun Gu Yeon Ju Kwon Jea Uk Lee Jin-Yong Hong 《International journal of molecular sciences》2022,23(9)
As the control over radioactive species becomes critical for the contemporary human life, the development of functional materials for decontamination of radioactive substances has also become important. In this work, a three-dimensional (3D) porous carbon monolith functionalized with Prussian blue particles was prepared through removal of colloidal silica particles from exfoliated graphene/silica composite precursors. The colloidal silica particles with a narrow size distribution were used to act a role of hard template and provide a sufficient surface area that could accommodate potentially hazardous radioactive substances by adsorption. The unique surface and pore structure of the functionalized porous carbon monolith was examined using electron microscopy and energy-dispersive X-ray analysis (EDS). The effective incorporation of PB nanoparticles was confirmed using diverse instrumentations such as X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). A nitrogen adsorption/desorption study showed that surface area and pore volume increased significantly compared with the starting precursor. Adsorption tests were performed with 133Cs ions to examine adsorption isotherms using both Langmuir and Freundlich isotherms. In addition, adsorption kinetics were also investigated and parameters were calculated. The functionalized porous carbon monolith showed a relatively higher adsorption capacity than that of pristine porous carbon monolith and the bulk PB to most radioactive ions such as 133Cs, 85Rb, 138Ba, 88Sr, 140Ce, and 205Tl. This material can be used for decontamination in expanded application fields. 相似文献
5.
A new organic–inorganic cation exchanger EDTA-stannic(IV)iodate was synthesized. The materials possess good chemical and thermal
stability. The exchanger was characterized on the basis of X-ray, TGA, FTIR, UV–Visible spectrophotometery and SEM studies.
ion exchange capacity, pH titration, elution and distribution studies were also carried out to determine the primary ion exchange
properties of the material. The SEM study confirms the fibrous nature of the material. The exchanger behaves as a monofunctional
cation exchanger with ion exchange capacity of 1.30 meq/g for Na+ ions. The material can perform well upto the temperature of 500 °C and retains the 76.4% of ion exchange capacity. The material
is fairly stable in dilute solutions of some common mineral acids, bases and organic solvents. The differential selectivity
of metal ions on EDTA-stannic(IV)iodate has been utilized to perform analytically and industrially important binary separations. 相似文献
6.
Muhammad Talha Mu. Naushad 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(4):822-829
To study the ion exchange kinetics of heavy metal ions on the organic–inorganic composite cation exchanger poly-o-toluidine Zr(IV) tungstate, Nernst–Planck was computer simulated. Simulated numerical results for counter ions (Cu, Zn, Cd and Pb) of equal valence and four different ionic mobilities are presented to understand the ionic diffusion process. These results are based on the fractional attainment of equilibrium U(τ), of the counter ions under study. The forward (M2+–H+) and reverse (H+–M2+) ion exchange processes are justified as the particle diffusion phenomenon. The self-diffusion coefficient (D o ), energy of activation (E a ), and entropy of activation (?S*) have also been estimated to understand the ion exchange process occurring over the surface of this cation exchanger and indicated that the ion exchange process is feasible and spontaneous. It is concluded that the difference in activation energies and entropy of activation may facilitate the separation of metal ions. The regeneration capability of this cation exchanger was also explained. 相似文献
7.
Molecular recognition based Fe3+ imprinted monolith was prepared for selective removal of Fe3+ ions from aqueous solutions. The precomplexation was achieved by the coordination of Fe3+ ions with N‐methacryloyl‐(L )‐cysteine methyl ester (MAC) to form the complex monomer (MAC‐Fe3+). The polymerization step was then carried out in the presence of MAC‐Fe3+ complex and hydroxyethyl methacrylate (HEMA) monomer by bulk polymerization to constitude a Fe3+‐imprinted polymer (PHEMAC‐Fe3+). The specific surface area of PHEMAC‐Fe3+ monolith was found to be 35.2 m2/g, with a swelling ratio of 60.2% after the template was removed from the monolith by 0.1M EDTA solution. The maximum adsorption capacity of PHEMAC‐Fe3+ monolith for Fe3+ ion was 0.76 mg/g. The adsorption behavior of the monolith has been successfully described by the Langmuir isotherm. It was determined that the relative selectivity of PHEMAC‐Fe3+ monolith was 59.7 and 37.0 times greater than that of the nonimprinted PHEMAC monolith as compared with the Cd2+ and Ni2+ ions, respectively. The PHEMAC‐Fe3+ monolith was recovered and reused many times without any significant decrease in its adsorption capacity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
8.
Ebru Çubuk Demiralay Muge Andac Rıdvan Say Guleren Alsancak Adil Denizli 《应用聚合物科学杂志》2010,117(6):3704-3714
Ni2+‐imprinted monolithic column was prepared for the removal of nickel ions from aqueous solutions. N‐Methacryloyl‐L ‐histidine was used as a complexing monomer for Ni2+ ions in the preparation of the Ni2+‐imprinted monolithic column. The Ni2+‐imprinted poly(hydroxyethyl methacrylate‐N‐methacryloyl‐L ‐histidine) (PHEMAH) monolithic column was synthesized by bulk polymerization. The template ion (Ni2+) was removed with a 4‐(2‐pyridylazo) resorcinol (PAR):NH3? NH4Cl solution. The water‐uptake ratio of the PHEMAH–Ni2+ monolith increased compared with PHEMAH because of the formation of nickel‐ion cavities in the polymer structure. The adsorption of Ni2+ ions on both the PHEMAH–Ni2+ and PHEMAH monoliths were studied. The maximum adsorption capacity was 0.211 mg/g for the PHEMAH–Ni2+ monolith. Fe3+, Cu2+, and Zn2+ ions were used as competitive species in the selectivity experiments. The PHEMAH–Ni2+ monolithic column was 268.8, 25.5, and 10.4 times more selective than the PHEMAH monolithic column for the Zn2+, Cu2+, and Fe3+ ions, respectively. The PHEMAH–Ni2+ monolithic column could be used repeatedly without a decrease in the Ni2+ adsorption capacity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
9.
《Polymer Composites》2017,38(5):1005-1013
Single‐walled carbon nanotubes cerium(IV) phosphate composite cation exchanger was synthesized using sol−gel method. The ion‐exchange properties such as elution concentration, elution behavior and effect of temperature on ion exchange capacity were studied. The composite cation exchange material showed an ion‐exchange capacity (IEC) of 1.64 meq dry g−1 of ion exchanger. The distribution studies revealed that the composite cation‐exchanger is highly selective for Cd(II) ions. The material was used as an electroactive component for the construction of a cadmium ion‐selective membrane electrode. The membrane electrode showed a Nernstian response for Cd(II) ions over a wide concentration range of 1 × 10−7−1 × 10−1 M with a sub‐Nernstian slope of 27.429 mV per decade change in concentration of cadmium ions. The limit of detection was found to be 1 × 10−7 M. It possessed a fast response time 10 s and can be utilized for 130 days without any considerable divergence in response potential. The practical utility of membrane electrode was demonstrated by employing as an indicator electrode for the potentiometric titration of Cd(II) with ethylenediamine tetra acetic acid, disodium salt (EDTA). POLYM. COMPOS., 38:1005–1013, 2017. © 2015 Society of Plastics Engineers 相似文献
10.
《大分子材料与工程》2017,302(10)
3D polypyrrole (3D‐PPy) monolith is prepared by a simple chemical oxidation of pyrrole monomer using FeCl3 as an oxidant. The as‐prepared PPy monolith exhibits an abundant porosity and with a mesopore size of about 9.1 nm in diameter. Taking advantage of its mesoprous feature as well as the unique chemical composition, the 3D‐PPy is employed as the porous medium for adsorption and removal of radioactive iodine from environment. A high iodine adsorption capacity of 1.6 g g−1 for 3D‐PPy is obtained which is competing with that of those reported porous organic polymers. Besides, the adsorption kinetics and adsorption thermodynamic experiments show that the adsorption is dominated by the pseudosecond‐order kinetics and Langmuir models. Considering its simple and low cost‐effective preparing method, unique monolithic porous as well as π–π conjugated chemical structure, the resulted 3D‐PPy may be found useful applications for removal of radioactive iodine to address environmental issues. 相似文献
11.
Light‐Addressable Potentiometric Sensor with Nitrogen‐Incorporated Ceramic Sm2O3 Membrane for Chloride Ions Detection
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A light‐addressable potentiometric sensor (LAPS) with ceramic samarium oxide (Sm2O3)‐sensing membrane treated by nitrogen plasma immersion ion implantation (PIII) has been proposed for chloride ion detection. For the pure Sm2O3‐LAPS, a potassium ion sensitivity of 39.21 mV/pK is obtained. With the nitrogen PIII treatment on Sm2O3‐sensing membrane, the N–O peak is observed by X‐ray photoelectron spectroscopy, implying the formation of positive charges, (N‐O)+ and (N‐O‐N)+, within the Sm2O3 film. The positive charges can attract the chloride ions to react with the surface sites of OH2+, achieving a superior chloride ion sensitivity of 36.17 mV/pCl for the Sm2O3‐LAPS with nitrogen PIII treatment. The LAPS structure with ceramic Sm2O3‐sensing membrane can be used for future biosensing applications, especially for the potassium and chloride ions detection in serum. 相似文献
12.
Poly(N‐isopropylacrylamide) gel‐based macroporous monolith for continuous‐flow recovery of palladium(II) ions
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Hirokazu Seto Hikaru Matsumoto Makoto Shibuya Takanori Akiyoshi Yu Hoshino Yoshiko Miura 《应用聚合物科学杂志》2017,134(4)
Macroporous monoliths, composed of thermoresponsive, tertiary‐aminated, and crosslinking monomers, were prepared for continuous‐flow separation of palladium(II) ions. N ‐Isopropylacrylamide was required to form the porous structure in the monoliths, indicating that the mechanism of porous structure formation involved polymerization‐induced phase separation of the poly(N ‐isopropylacrylamide) gel. Tertiary‐aminated monoliths showed adsorption selectivity for palladium(II) ions in hydrochloric media, compared with copper(II) ions. The maximum capacities of the monoliths with tertiary amine contents of 10, 20, 30, and 70 mol % for palladium(II) ions were 0.6, 1.1, 1.3, and 2.3 mmol/g, respectively. Darcy's permeabilities of water through the macroporous monolith were 10?14 to 10?13 m2, and those were comparable to that through a commercially available membrane filter with a pore size of several micrometers. In the continuous‐flow process, the macroporous monolith with tertiary amine selectively adsorbed palladium(II) ions in the coexistence of copper(II) ions with 10 times higher concentration than the palladium(II) ions. The palladium(II) ions were eluted from the macroporous monolith, and the concentration of palladium(II) ions in the eluate was up to 45 times of that in the feed solution. The average enrichment factor and total recovery percentage of palladium(II) ions were 8.7 times and 95%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44385. 相似文献
13.
《分离科学与技术》2012,47(2):256-261
A selective and reliable method has been developed for the extraction and separation of mercuric ion with cross-linked graft copolymer of acrylic acid based on sorption-desorption studies. The graft copolymer acts as an ion exchanger. The physico-chemical properties of the exchanger, and optimum pH, time, and temperature for Hg2+ adsorption were determined. Metal ion adsorption kinetics, isotherms, and thermodynamics have been studied. A plausible mechanism for mercury ion extraction has been suggested. Mercuric ion has been separated quantitatively from various synthetic mixtures containing metal ions (Ni2+, Cd2+, Pb2+, and Zn2+). 相似文献
14.
《分离科学与技术》2012,47(14):3695-3711
Abstract A crystalline sample of organic-inorganic cation exchanger acrylamide aluminumtungstate has been synthesized. The material behaves as a mono-functional cation-exchanger with an ion–exchange capacity 1.25 meq/g for Na+ ions. The material has been characterized on the basis of thermal stability, chemical stability, FTIR, TGA-DTA, X-ray, and SEM studies. The effect of time and temperature on the distribution coefficient of metal ion was studied. It was concluded that 30°C appeared to be the most favorable temperature. Sorption behavior of the metal ions was studied in different solvent systems. On the basis of distribution studies, the material was found to be selective for Pb2+ ions. Its selectivity was examined by achieving some important binary separations like Mg2+-Pb2+, Hg2+-Pb2+, Ca2+-Pb2+ Zn2+-Pb2+, Ni2+-Pb2+, and Al3+-Pb2+. The practical applicability of the cation-exchanger was demonstrated in the separation of Pb2+ ions from a synthetic mixture. 相似文献
15.
A novel monolithic material was developed to obtain efficient and cost‐effective purification of IgG from human plasma. The porous monolith was obtained by bulk polymerization in a glass tube of 2‐hydroxyethyl methacrylate (HEMA) and N‐methacryloyl‐(L )‐histidine methyl ester (MAH). The poly(HEMA‐MAH) monolith had a specific surface area of 214.6 m2/g and was characterized by swelling studies, porosity measurement, FTIR, scanning electron microscopy, and elemental analysis. Then the monolith was loaded with Cu2+ ions to form the metal chelate. Poly(HEMA‐MAH) monolith with a swelling ratio of 74% and containing 20.9 μmol MAH/g was used in the adsorption/desorption of IgG from aqueous solutions and human plasma. The maximum adsorption of IgG from an aqueous solution in phosphate buffer was 10.8 mg/g at pH 7.0. Higher adsorption was obtained from human plasma (up to 104.2 mg/g), with a purity of 94.1%. It was observed that IgG could be repeatedly adsorbed and desorbed with the poly(HEMA‐MAH) monolith without significant loss of adsorption capacity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 395–404, 2006 相似文献
16.
《分离科学与技术》2012,47(1):164-178
Abstract The adsorption of different metal ions on acrylamidezirconium (IV) arsenate has been studied. The effect of surfactant concentration (Tween 80‐R and Tritron X‐100) on sorption of different metal ions acrylamidezirconium (IV) arsenate was explored. The effect of experimental parameters such as contact time, temperature, and pH on adsorption of Pb2+ions was studied. The promising feature of the material is its specificity for Pb2+ ions. A new PVC based Pb2+ ion‐selective electrode using acrylamidezirconium (IV) arsenate as electro‐active material has been fabricated. The electrode works well over a wide range of concentration 1×10?1 M–1×10?7 M with a Nerstian slope of 30±1 mV per decade. The sensor shows the short response time of 20 seconds and can operate in the pH range of 2–7. The sensor can be used for the period of over 4 months with out deviation in response characteristics. The electrode has been successfully used as an indicator electrode for potentiometric titration of Pb2+ ions in solution against EDTA solution. 相似文献
17.
To improve the electrical conductivity of polyacrylonitrile (PAN) film, metallic sulfides and PAN composite film were prepared by the chelating method. Dense PAN film and porous PAN film were prepared by dry process and wet process, respectively. These PAN films were treated to NH2OH solution to introduce the amidoxime group coordinated with metallic ion. Cu+2 and Cd+2 ions were adsorbed to amidoximated PAN films, the sulfur ion was treated with metal-adsorbed PAN films, and thus CuS—and CdS–PAN composite films were prepared. The adsorptive capacity of amidoximated PAN film for the Cu+2 ion was independent of the morphology of the PAN film, but the adsorptive capacity of the Cd+2 ion on amidoximated PAN film was dependent on porosity of the polymer. Adsorptive capacity of amidoximated porous PAN film for Cd+2 was improved about four times than that of amidoximated dense PAN film. The electrical conductivities of CuS–dense and porous PAN composite film were both 10?1 S/cm in optimum condition, but because of the difference in adsorptive capacity, the electrical conductivities of CdS–dense and CdS–porous PAN composite films were 10?9 S/cm and 10?4 S/cm, respectively. Additionally, because CdS was known as a photoconductive material, the photoconductive properties of CdS–porous PAN composite film were investigated. 相似文献
18.
This Account describes recent work in the development and applications of sol-gel sensors for concentrated strong acids and bases and metal ions. The use of sol-gel films doped with organic indicators for the optical sensing of concentrated strong acids (HCl, 1-10 M) and bases (NaOH, 1-10 M) has been explored, and the development of dual optical sensor approaches for ternary systems (HCl-salt-H 2O and NaOH-alcohol-H 2O) to give acid and salt, as well as base and alcohol, concentrations is discussed. The preparation of transparent, ligand-grafted sol-gel monoliths is also described, and their use in the analysis of both metal cations (Cu (2+)) and metal anions [Cr(VI)] is presented. A new model using both metal ion diffusion and immobilization by the ligands in such monoliths has been developed to give metal concentrations using the optical monolith sensors. In addition to optical sensing, a method utilizing ligand-grafted sol-gel films for analyte preconcentration in the electrochemical determination of Cr(VI) has been explored and is discussed. 相似文献
19.
Sequestration and removal of heavy metal ions from aqueous solutions pose multiple challenges. Ease of synthesis, high adsorption capacity and ease of regeneration are important considerations in the design of polymeric adsorbent materials developed for this purpose. To meet this objective, a new approach was used to design and synthesize a highly porous polystyrene-based resin (IDASR15) bearing iminodiacetate functional groups in every repeat unit by free radical polymerization with N, N'-methylenebisacrylamide as crosslinker followed by base hydrolysis. The physiochemical chemical properties of the resin were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, equilibrium swelling value (ESV) and thermogravimetric analysis. Metal uptake capacity of IDASR15 towards low concentrations of various toxic heavy metal ions such as Cu2+, Cd2+, Mn2+, Zn2+, Pb2+, Ni2+, Co2+, Co3+, Cr3+, Fe2+, Fe3+, and Al3+ were investigated from their aqueous solution by batch method and found to be 0.943–2.802 mmol/g. The maximum capacity was 2.802 mmol/g obtained for Cu2+ ion at pH 5. The potential for regeneration and reuse has been demonstrated with Cu2+ ion by batch and column methods. The reported results suggest that IDASR15 is a highly efficient and porous complexing agent for commonly found toxic metal ions in aqueous streams with a high ESV of 68.55 g of water/1.0 g of IDASR15. It could also be reused ~99.5% of adsorption efficiency which is very promising and holds significant potential for waste-water treatment applications. 相似文献
20.
Nazia Iqbal Mohammad Mobin M.Z.A. Rafiquee Hamad A. Al-Lohedan 《Chemical Engineering Research and Design》2012
A new cationic exchange material, sodium bis(2-ethylhexyl) sulfosuccinate (AOT) with cerium (IV) phosphate (AOT–CeP) has been synthesized. The characterization of the ion exchanger was performed by using infra red spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermo gravimetric analysis/differential thermo gravimetric analysis (TGA/DTA/DTG) and elemental analysis. The ion exchange properties like ion exchange capacity, elution and concentration behavior of AOT–CeP were determined by taking the material into a column and elution of H+ was done by NaNO3. The thermal stability of the ion exchanger was studied by determining ion exchange capacity after heating to different temperatures for one hour. The adsorption studies on AOT–CeP demonstrated that the material is selective for Cu2+, Pb2+, Cd2+, Zn2+ and Hg2+ ions. AOT–CeP was found to be effective for the separation of Cu2+, Pb2+, Cd2+, Zn2+ and Hg2+ ions in the presence of alkali metals/alkaline earth metals. This cationic exchanger was also effective for the removal of Cu2+, Pb2+, Cd2+, Zn2+ and Hg2+ ions in the presence of acid and other transition metal ions. Thus, AOT–CeP can be used for the removal of these ions from the waste water during its treatment. 相似文献