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In this study, Poly(ethylene glycol dimethacrylate-N-methacryloyl-L-tryptophan methyl ester) [poly(EGDMA-MATrp)] beads (average diameter = 106–300 μm) which were synthesized by copolymerizing of N-methacryloyl-L-tryptophan methyl ester (MATrp) with ethylene glycol dimethacrylate (EGDMA) were used for diethyl phthalate (DEP) adsorption. The various factors affecting the adsorption of DEP from aqueous solutions such as pH, initial concentration, contact time and temperature were analyzed. Adsorption behaviour of DEP on the poly (EGDMA-MATrp) beads was investigated by varying pH values of solution, contact time, initial concentration and temperature. An optimum adsorption capacity of 590.7 mg g−1 for DEP was obtained at 25°C. The present adsorption process obeyed pseudo-second-order kinetic model. All the isotherm data can be fitted with the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. Thermodynamic parameters ΔH = 7.745 kJ mol−1, ΔS = 81.92 J K−1 mol−1, and ΔG = -16.69 kJ mol−1 to -18.31 kJ mol−1 with the rise in temperature from 25°C to 45°C indicated the adsorption process was endothermic and spontaneous.Supplementary material

Ortalama çapı 53-212 μm olan mezogözenekli manyetik-poli(divinilbenzen-ko-vinilimidazol) (mpoli(DVB-VIM)) mikrokürelerinin hazırlanması için modifiye süspansiyon polimerizasyonu kullanıldı. Mikrokürelerin spesifik yüzey alanı 29.47 m2g-1 ve Fe3O4 ilavesiyle birlikte, DVB/VIM mol oranı 4:1 mol/mol olarak belirlendi. Fizikokimyasal çalışmalar m-poli (DVB-VIM) mikroküreleri üzerine pH, başlangıç konsantrasyonu, mikroküre miktarı, temas süresi ve sıcaklık gibi parametrelerle incelendi. m-poli(DVB-VIM) mikrokürelerinin Ni(II) iyonlarına karşı maksimum adsorpsiyon kapasitesi 277 K, 298 K, 318 K ve 338 K’de sırasıyla 13.51, 20.14, 21.00 ve 23.62 mg.g-1 olarak belirlendi. Sistemin dinamik ve denge adsorpsiyon davranışları sırasıyla yalancı ikinci derece model ve Langmuir izoterm modeliyle açıklandı. Gibbs serbest enerji değişimi (ΔG0), standart entalpi değişimi (ΔH0) ve standart entropi değişimi (ΔS0) gibi termodinamik parametreler belirlendi. Ayrıca adsorpsiyonda kullanımdan sonra, paramanyetik özellikli m-poli (DVB-VIM) mikroküreleri uygulanan manyetik kuvvet yardımıyla ayrıldı. Bu sonuçlar, çalışılan malzemenin manyetik alan altında su ve atık sulardan Ni(II) iyonlarının uzaklaştırılması için kullanılabilir olduğunu gösterdi.

This study is aimed at the synthesis and characterization of the mesoporous magnetic-poly(divinylbenzene-1-vinylimidazole)[m-poly(DVB-VIM))microbeads(average diameter = 53-212 mu m); their application as adsorbent in the removal of Cu(II) ions from aqueous solutions was investigated. The mesoporous m-poly(DVB-VIM) microbeads were prepared by copolymerizing of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The mesoporous m-poly(DVB-VIM) microbeads were characterized by N-2 adsorption/desorption isotherms, ESR, elemental analysis, scanning electron microscope (SEM), and swelling studies. At fixed solid/solution ratio the various factors affecting adsorption of Cu(II) ions from aqueous solutions such as pH, initial concentration, amount of mesoporousm-poly(DVB-VIM)) microbeads, contact time, and temperature were analyzed. Langmuir, Freundlich, and Dubinin-Radushkvich isotherms were used the model adsorption equilibrium data. The Langmuir isotherm model was the most adequate. The pseudo first-order, pseudo-second-order, Ritch-second-order, and intraparticle diffusion models were used to describe the adsorption kinetics. The experimental data fitted to pseudo second-order kinetic. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. Morever, after the use in adsorption, the mesoporous m-poly(DVB-VIM) microbeads with paramagnetic property was separated via the applied magnetic force. These features make the mesoporous m-poly(DVB-VIM) microbeads a potential candidate for support of Cu(II) ions removal under magnetic field.

Magnetic vinylphenyl boronic acid microparticles, poly(ethylene glycol dimethacrylate(EG)-vinylphenyl boronic acid(VPBA)) [m-poly(EG-VPBA)], produced by suspension polymerization and characterized, was found to be an efficient solid polymer for Cr(VI) adsorption. The m-poly(EG-VPBA) microparticles were prepared by copolymerizing of ethylene glycol dimethylacrylate (EG) with 4-vinyl phenyl boronic acid (VPBA). The m-poly(EG-VPBA) microparticles were characterized by N-2 adsorption/desorption isotherms, electron spin resonance (ESR), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), elemental analysis, scanning electron microscope (SEM) and swelling studies. The m-poly(EG-VPBA) microparticles were used at adsorbent/Cr(VI) ion ratios. The influence of pH, Cr(VI) initial concentration, temperature of the removal process was investigated. The maximum removal of Cr(VI) was observed at pH 2. Langmuir isotherm and Dubinin-Radushkvich isotherm were found to better fit the experiment data rather than Fruendlich isotherm. The kinetics of the adsorption process of Cr(VI) on the m-poly(EG-VPBA) microparticles were investigated using the pseudo first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models, results showed that the pseudo-second order equation model provided the best correlation with the experimental results. The thermodynamic parameters (free energy change, Delta G(0) enthalpy change, Delta H-0; and entropy change, Delta S-0) for the adsorption have been evaluated.

In this study, the use of the potentiometric method for the determination of the protonation constant of vinyl imidazole (VIM) and the stability constant of the Cu2+ ion complex of VIM used in the immobilized metal ion affinity chromatography (IMAC) was investigated. For this purpose, poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA–VIM)] microspheres (average diameter 150–200 μm) were prepared. The microspheres were characterized by elemental analysis, N2 adsorption/desorption isotherms, elemental analysis, energy dispersive spectroscopy (EDS). Protonation constants of vinyl imidazole and the metal-ligand stability constant of vinyl imidazole with Cu2+ ions have been determined potentiometrically in 0.1M NaCl aqueous solution at 298, 318, and 338 K, respectively. The corresponding thermodynamic parameters of protonation and complexation processes (ΔG, ΔH, and ΔS) were derived and discussed. The formation kinetics of Cu2+-vinyl imidazole complex were also investigated, and the process obeyed the pseudo-second-order kinetic model. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39751.

Poly(ethylene glycol dimethacrylate-N-methacryloyl-L-tryptophan methyl ester) [poly(EGDMA-MATrp)] beads (average diameter = 106-300 mu m) were synthesized by copolymerizing of N-methacryloyk-L-typtophan methyl ester (MATrp) with ethylene glycol dimethacrylate (EGDMA). The usability of newly synthesized material for the removal of dimethyl phthalate (DMP) from aqueous phase was investigated. The poly (EGDMA-MATrp) beads were characterized by N-2 adsorption/desorption isotherms (BET), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and swelling studies. Initial concentration, pH, contact time and temperature effects on the adsorption of DMP from aqueous solutions were analyzed. An optimum adsorption capacity of 237.3 mg g(-1), for DMP was obtained at 25 degrees C. The present adsorption process obeyed pseudo-second-order kinetic model. All the isotherm data can be fitted with both the Langmuir, and the Dubinin-Radushkevich isotherm models with high correlation coefficients. Thermodynamic parameters Delta N = 2.398 kJ mol(-1), Delta S = 65.76 J K-1 mol(-1), and Delta G = 17.20 kJ mol(-1) to -18.57 kJ mol(-1) with the rise in temperature from 25 degrees C to 45 degrees C indicated the adsorption process was endothermic and spontaneous. The DMP adsorption capacity did not change after 10 batch successive reactions, demonstrating the usefulness of the beads in applications.

Removal of Pb(II) ions from electroplating wastewater of Bursa, an industrial city in Turkey, was investigated in fixed-bed column. The experiments were conducted to study the effect of important design parameters such as column bed height and flow rate. The breakthrough profiles were obtained in these studies. At a bed height of 14 cm and flow rate of 6 mL/min, the metal-uptake capacity of poly(ethylene glycol dimethacrylate-1-vinylimidazole) [poly(EGDMA-VIM)] beads for Pb(II) ions was found to be 90 mg/g. Bed Depth Service Time (BDST) model was used to analyse the experimental data and evaluate the performance of adsorption column. For various flow rates, adsorption capacity per unit bed volume (N0) and adsorption rate constant (ka) are in the range of 2370–3560 mg/mL and 0.0225–0.0616 L/mg h, respectively. The saturated column was easily regenerated by 0.1 M HNO3and the poly(EGDMA-VIM) beads in fixed-bed column could be reused for Pb(II) ions removal.

The magnetic-poly(divinylbenzene-1-vinylimidazole) [m-poly(DVB-VIM)] microbeads (average diameter 53-212 mu m) were synthesized and characterized; their use as adsorbent in removal of Cr(VI) ions from aqueous solutions was investigated. The m-poly(DVB-VIM) microbeads were prepared by copolymerizing of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The m-poly(DVB-VIM) microbeads were characterized by N-2 adsorption/desorption isotherms, ESR, elemental analysis, scanning electron microscope (SEM) and swelling studies. At fixed solid/solution ratio the various factors affecting adsorption of Cr(VI) ions from aqueous solutions such as pH, initial concentration, contact time and temperature were analyzed. Langmuir, Freundlich and Dubinin-Radushkvich isotherms were used as the model adsorption equilibrium data. Langmuir isotherm model was the most adequate. The pseudo-first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models were used to describe the adsorption kinetics. The apparent activation energy was found to be 5.024 kJ mol(-1), which is characteristic of a chemically controlled reaction. The experimental data fitted to pseudo-second-order kinetic. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes. The thermodynamic parameters obtained indicated the endothermic nature of adsorption of Cr(VI) ions. Morever, after the use in adsorption, the m-poly(DVB-VIM) microbeads with paramagnetic property were separeted via the applied magnetic force. The magnetic beads could be desorbed up to about 97% by treating with 1.0 M NaOH. These features make the m-poly(DVB-VIM) microbeads a potential candidate for support of Cr(VI) ions removal under magnetic field.

Designing an immobilised metal ion affinity process on large-scale demands that a thorough understanding be developed regarding the adsorption behaviour of proteins on metal-loaded gels and the characteristic adsorption parameters to be evaluated. In view of this requirement, interaction of alpha-amylase as a model protein with newly synthesised magnetic-poly(divinylbenzene-1-vinylimidazole) [m-poly(DVB-VIM)] microbeads (average diameter, 53-212 mu m) was investigated. The m-poly(DVB-VIM) microbeads were prepared by copolymerising of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The m-poly(DVB-VIM) microbeads were characterised by N-2 adsorption/desorption isotherms, electron spin resonance, elemental analysis, scanning electron microscope and swelling studies. Cu2+ ions were chelated on the m-poly(DVB-VIM) beads and used in adsorption of alpha-amylase in a batch system. The maximum alpha-amylase adsorption capacity of the m-poly(DVB-VIM)-Cu2+ beads was determined as 10.84 mg/g at pH 6.0, 25 A degrees C. The adsorption data were analyzed using three isotherm models, which are the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The pseudo-first-order, pseudo-second-order, modified Ritchie's-second-order and intraparticle diffusion models were used to test dynamic experimental data. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes.