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An assessment on the interaction of a hydrophilic ionic liquid with different sorbents / K. Vijayaraghavan in Industrial & engineering chemistry research, Vol. 48 N° 15 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7283–7288 Titre : An assessment on the interaction of a hydrophilic ionic liquid with different sorbents Type de document : texte imprimé Auteurs : K. Vijayaraghavan, Auteur ; Thi Phuong Thuy Pham, Auteur ; Chul-Woong Cho, Auteur Année de publication : 2009 Article en page(s) : pp. 7283–7288 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Ionic  liquids  1-butyl-3-methylimidazolium  chloride  Sorption  media Résumé : Ionic liquids have received an upsurge in interest as green solvents, primarily as replacements for conventional media in chemical processes. This growing interest may soon lead to their presence in the environment. To evaluate the environmental fate of ionic liquids, their sorption onto different media is an essential parameter. This study presents an experimental verification of the sorption of 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) onto different sorption media. The examined sorption media included two activated carbons (SPS-200 and SPC-100), an ion-exchange resin (IER), a fermentation waste (Corynebacterium glutamicum), and a dried activated sludge. Through HPLC and MS/MS analysis, [BMIM][Cl] was found to be stable only in the pH range 3 to 11. The experimental results reveal that removal of [BMIM][Cl] was only possible using IER and the two forms of activated carbon. The equilibrium solution pH was found to have no significant effect on the sorption ability of IER, whereas, both forms of activated carbon exhibited high sorption under strong alkaline conditions. No significant sorption of [BMIM] was observed with both C. glutamicum and the activated sludge. According to the Langmuir model, the IER can sorb as much as 179.4 mg [BMIM]/g, whereas those of SPS-200 and SPC-100 were 20.6 and 19.6 mg [BMIM]/g, respectively. The sorption kinetics was found to be rapid, with only 15 and 60 min required to attain equilibrium for IER and the two forms of activated carbon, respectively. Only IER exhibited significant sorption ability toward chloride ions which are an anionic part of the IL. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801825q [article] An assessment on the interaction of a hydrophilic ionic liquid with different sorbents [texte imprimé] / K. Vijayaraghavan, Auteur ; Thi Phuong Thuy Pham, Auteur ; Chul-Woong Cho, Auteur . - 2009 . - pp. 7283–7288. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7283–7288 Mots-clés : Ionic  liquids  1-butyl-3-methylimidazolium  chloride  Sorption  media Résumé : Ionic liquids have received an upsurge in interest as green solvents, primarily as replacements for conventional media in chemical processes. This growing interest may soon lead to their presence in the environment. To evaluate the environmental fate of ionic liquids, their sorption onto different media is an essential parameter. This study presents an experimental verification of the sorption of 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) onto different sorption media. The examined sorption media included two activated carbons (SPS-200 and SPC-100), an ion-exchange resin (IER), a fermentation waste (Corynebacterium glutamicum), and a dried activated sludge. Through HPLC and MS/MS analysis, [BMIM][Cl] was found to be stable only in the pH range 3 to 11. The experimental results reveal that removal of [BMIM][Cl] was only possible using IER and the two forms of activated carbon. The equilibrium solution pH was found to have no significant effect on the sorption ability of IER, whereas, both forms of activated carbon exhibited high sorption under strong alkaline conditions. No significant sorption of [BMIM] was observed with both C. glutamicum and the activated sludge. According to the Langmuir model, the IER can sorb as much as 179.4 mg [BMIM]/g, whereas those of SPS-200 and SPC-100 were 20.6 and 19.6 mg [BMIM]/g, respectively. The sorption kinetics was found to be rapid, with only 15 and 60 min required to attain equilibrium for IER and the two forms of activated carbon, respectively. Only IER exhibited significant sorption ability toward chloride ions which are an anionic part of the IL. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801825q

Antimonite removal using marine algal species / K. Vijayaraghavan in Industrial & engineering chemistry research, Vol. 50 N° 17 (Septembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 9864-9869 Titre : Antimonite removal using marine algal species Type de document : texte imprimé Auteurs : K. Vijayaraghavan, Auteur ; R. Balasubramanian, Auteur Année de publication : 2011 Article en page(s) : pp. 9864-9869 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Antimonite  Marine  algal Résumé : Three seaweed species (Turbinaria conoides, Sargassum sp., and Ulva sp.) were examined to assess their ability to sequester antimonite [Sb(III)] ions from aqueous solution. Among these species, both T. conoides and Sargassum sp. showed higher Sb(III) biosorption potential than Ulva sp. The pH-edge experimental results revealed the involvement of negatively charged groups in the biosorption of Sb(III). Biosorption isotherms obtained at pH 6 indicated that T. conoides provided higher uptake of Sb(III) (18.1 mg/g) than Sargassum sp. (14.9 mg/g) according to the Langmuir model. Kinetic studies indicated that the rates of Sb(III) removal by both brown seaweeds were high, with 95% of the process completed within 45 min. A pseudo-first-order model was found to describe the kinetic data satisfactorily with a high correlation coefficient and low percentage errors. Desorption experiments with 0.1 M HCl showed that it is possible to regenerate T. conoides for its continued use as a biosorbent for up to three sorption–desorption cycles without significant loss in sorption capacity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200776m [article] Antimonite removal using marine algal species [texte imprimé] / K. Vijayaraghavan, Auteur ; R. Balasubramanian, Auteur . - 2011 . - pp. 9864-9869. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 9864-9869 Mots-clés : Antimonite  Marine  algal Résumé : Three seaweed species (Turbinaria conoides, Sargassum sp., and Ulva sp.) were examined to assess their ability to sequester antimonite [Sb(III)] ions from aqueous solution. Among these species, both T. conoides and Sargassum sp. showed higher Sb(III) biosorption potential than Ulva sp. The pH-edge experimental results revealed the involvement of negatively charged groups in the biosorption of Sb(III). Biosorption isotherms obtained at pH 6 indicated that T. conoides provided higher uptake of Sb(III) (18.1 mg/g) than Sargassum sp. (14.9 mg/g) according to the Langmuir model. Kinetic studies indicated that the rates of Sb(III) removal by both brown seaweeds were high, with 95% of the process completed within 45 min. A pseudo-first-order model was found to describe the kinetic data satisfactorily with a high correlation coefficient and low percentage errors. Desorption experiments with 0.1 M HCl showed that it is possible to regenerate T. conoides for its continued use as a biosorbent for up to three sorption–desorption cycles without significant loss in sorption capacity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200776m

Biosorption of As(V) onto the shells of the crab (portunus sanguinolentus) / K. Vijayaraghavan in Industrial & engineering chemistry research, Vol. 48 N° 7 (Avril 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 7 (Avril 2009) . - pp. 3589–3594 Titre : Biosorption of As(V) onto the shells of the crab (portunus sanguinolentus) : equilibrium and kinetic studies Type de document : texte imprimé Auteurs : K. Vijayaraghavan, Auteur ; Mahadevan Arun, Auteur ; Umid Man Joshi, Auteur Année de publication : 2009 Article en page(s) : pp. 3589–3594 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Crab  shells  Arsenic(V)  Aqueous  solution  Systematic  equilibrium  Kinetic  studies Résumé : Worldwide concerns over inorganic arsenic in water bodies have prompted much research and policy development focusing on removal of this chronic human carcinogen. In the present study, the potential use of shell particles of crab (Portunus sanguinolentus) for removal of arsenic(V) from aqueous solution was investigated on the basis of systematic equilibrium and kinetic studies. Crab shells favor the removal of arsenate ion, especially under acidic pH conditions, because of the presence of CaCO3 and chitin in the biosorbent. The scanning electron micrographs together with energy dispersive X-ray analysis (EDX) confirmed the presence of arsenic on the crab shells. A series of isotherm experiments conducted at different pH conditions revealed that pH 3 favored arsenic biosorption. Among the four isotherm models (Langmuir, Freundlich, Redlich−Peterson, and Toth) employed in the study, the Toth model provided a better fit with the experimental data than others as revealed by high correlation coefficients, low % error, and root-mean-square error (rmse) values. The arsenic biosorption kinetics was very fast, and the kinetics data were successfully modeled using nonlinear pseudo-second-order model. As the ionic strength increased, arsenic uptake declined to a great extent. Desorption experiments were conducted to explore the feasibility of regenerating the biosorbent for further use. Results indicated that 0.1 M NaOH was sufficiently strong to remove the biosorbed arsenate ions from the crab shell with elution efficiency of 98.2%. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801570v [article] Biosorption of As(V) onto the shells of the crab (portunus sanguinolentus) : equilibrium and kinetic studies [texte imprimé] / K. Vijayaraghavan, Auteur ; Mahadevan Arun, Auteur ; Umid Man Joshi, Auteur . - 2009 . - pp. 3589–3594. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 7 (Avril 2009) . - pp. 3589–3594 Mots-clés : Crab  shells  Arsenic(V)  Aqueous  solution  Systematic  equilibrium  Kinetic  studies Résumé : Worldwide concerns over inorganic arsenic in water bodies have prompted much research and policy development focusing on removal of this chronic human carcinogen. In the present study, the potential use of shell particles of crab (Portunus sanguinolentus) for removal of arsenic(V) from aqueous solution was investigated on the basis of systematic equilibrium and kinetic studies. Crab shells favor the removal of arsenate ion, especially under acidic pH conditions, because of the presence of CaCO3 and chitin in the biosorbent. The scanning electron micrographs together with energy dispersive X-ray analysis (EDX) confirmed the presence of arsenic on the crab shells. A series of isotherm experiments conducted at different pH conditions revealed that pH 3 favored arsenic biosorption. Among the four isotherm models (Langmuir, Freundlich, Redlich−Peterson, and Toth) employed in the study, the Toth model provided a better fit with the experimental data than others as revealed by high correlation coefficients, low % error, and root-mean-square error (rmse) values. The arsenic biosorption kinetics was very fast, and the kinetics data were successfully modeled using nonlinear pseudo-second-order model. As the ionic strength increased, arsenic uptake declined to a great extent. Desorption experiments were conducted to explore the feasibility of regenerating the biosorbent for further use. Results indicated that 0.1 M NaOH was sufficiently strong to remove the biosorbed arsenate ions from the crab shell with elution efficiency of 98.2%. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801570v

Biosorption of lanthanum, cerium, europium, and ytterbium by a brown marine alga, turbinaria conoides / K. Vijayaraghavan in Industrial & engineering chemistry research, Vol. 49 N° 9 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp 4405–4411 Titre : Biosorption of lanthanum, cerium, europium, and ytterbium by a brown marine alga, turbinaria conoides Type de document : texte imprimé Auteurs : K. Vijayaraghavan, Auteur ; M. Sathishkumar, Auteur ; R. Balasubramanian, Auteur Année de publication : 2010 Article en page(s) : pp 4405–4411 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Biosorption Résumé : The ability of a brown marine alga, Turbinaria conoides, to remove four rare-earth elements (REEs; lanthanum, cerium, europium, and ytterbium) was evaluated. Results showed that T. conoides was an excellent biosorbent for all four REEs. The equilibrium pH was found to severely affect the biosorption performance; pH 4.9 ± 0.2 was found to be an optimum pH for favorable biosorption of REEs. The biosorption mechanism was found to proceed mainly by ion-exchange reactions between the lanthanide ions and the carboxyl groups present on the algal surface, confirmed by the pH edge, desorption, and scanning electron microscopy/energy-dispersive X-ray results. Biosorption isotherms were modeled using the Langmuir, Freundlich, and Toth isotherms, with the latter-described REE isotherms with very high correlation coefficients and lower error values. Maximum biosorption uptakes, according to the Langmuir model, were recorded as 154.7, 152.8, 138.2, and 121.2 mg/g for La, Ce, Eu, and Yb, respectively. Biosorption kinetics of REEs was found to be rapid, achieving 90% of total biosorption within 50 min. Desorption was successful with 0.05 M HCl, and the biomass was regenerated and reused for three sorption−desorption cycles without a significant loss in the biosorption capacity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000373 [article] Biosorption of lanthanum, cerium, europium, and ytterbium by a brown marine alga, turbinaria conoides [texte imprimé] / K. Vijayaraghavan, Auteur ; M. Sathishkumar, Auteur ; R. Balasubramanian, Auteur . - 2010 . - pp 4405–4411. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp 4405–4411 Mots-clés : Biosorption Résumé : The ability of a brown marine alga, Turbinaria conoides, to remove four rare-earth elements (REEs; lanthanum, cerium, europium, and ytterbium) was evaluated. Results showed that T. conoides was an excellent biosorbent for all four REEs. The equilibrium pH was found to severely affect the biosorption performance; pH 4.9 ± 0.2 was found to be an optimum pH for favorable biosorption of REEs. The biosorption mechanism was found to proceed mainly by ion-exchange reactions between the lanthanide ions and the carboxyl groups present on the algal surface, confirmed by the pH edge, desorption, and scanning electron microscopy/energy-dispersive X-ray results. Biosorption isotherms were modeled using the Langmuir, Freundlich, and Toth isotherms, with the latter-described REE isotherms with very high correlation coefficients and lower error values. Maximum biosorption uptakes, according to the Langmuir model, were recorded as 154.7, 152.8, 138.2, and 121.2 mg/g for La, Ce, Eu, and Yb, respectively. Biosorption kinetics of REEs was found to be rapid, achieving 90% of total biosorption within 50 min. Desorption was successful with 0.05 M HCl, and the biomass was regenerated and reused for three sorption−desorption cycles without a significant loss in the biosorption capacity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000373

Equilibrium isotherm studies for the multicomponent adsorption of lead, zinc, and cadmium onto Indonesian peat / R. Balasubramanian in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - p. 2093–2099 Titre : Equilibrium isotherm studies for the multicomponent adsorption of lead, zinc, and cadmium onto Indonesian peat Type de document : texte imprimé Auteurs : R. Balasubramanian, Auteur ; S. V. Perumal, Auteur ; K. Vijayaraghavan, Auteur Année de publication : 2009 Article en page(s) : p. 2093–2099 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Indonesian  peat  Pb  Cadmium  Zinc  Langmuir  two-site  model Résumé : This study evaluates the potential of Indonesian peat to sequester Pb, Cd, and Zn in single-, double-, and triple-solute systems. The adsorption isotherms of Pb, Cd, and Zn onto peat in single-solute and multisolute systems were simulated using the Langmuir two-site model satisfactorily. The model and experimental data of binary and ternary systems demonstrated that the presence of the secondary metal ions in the system resulted in a decrease in the sorption capacity of the primary metal, mainly because of the competitive effects of metals for adsorption sites. The metal adsorption follows the order of sequence Pb > Cd > Zn for both single-solute and multisolute systems. A three-dimensional representation of the total metal uptake in binary systems showed a good agreement with the corresponding experimental data. In addition to ion exchange, a surface adsorption−complexation mechanism must be involved in the sorption mechanism of metal ions. Fourier transform IR results confirm that the carboxyl functional groups participated in metal binding. Desorption experiments revealed that greater than 90% of Pb, Cd, and Zn can be eluted from the peat. In addition, results suggested that the desorption efficiency decreased with an increase in the adsorbed metal concentration. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801022p [article] Equilibrium isotherm studies for the multicomponent adsorption of lead, zinc, and cadmium onto Indonesian peat [texte imprimé] / R. Balasubramanian, Auteur ; S. V. Perumal, Auteur ; K. Vijayaraghavan, Auteur . - 2009 . - p. 2093–2099. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - p. 2093–2099 Mots-clés : Indonesian  peat  Pb  Cadmium  Zinc  Langmuir  two-site  model Résumé : This study evaluates the potential of Indonesian peat to sequester Pb, Cd, and Zn in single-, double-, and triple-solute systems. The adsorption isotherms of Pb, Cd, and Zn onto peat in single-solute and multisolute systems were simulated using the Langmuir two-site model satisfactorily. The model and experimental data of binary and ternary systems demonstrated that the presence of the secondary metal ions in the system resulted in a decrease in the sorption capacity of the primary metal, mainly because of the competitive effects of metals for adsorption sites. The metal adsorption follows the order of sequence Pb > Cd > Zn for both single-solute and multisolute systems. A three-dimensional representation of the total metal uptake in binary systems showed a good agreement with the corresponding experimental data. In addition to ion exchange, a surface adsorption−complexation mechanism must be involved in the sorption mechanism of metal ions. Fourier transform IR results confirm that the carboxyl functional groups participated in metal binding. Desorption experiments revealed that greater than 90% of Pb, Cd, and Zn can be eluted from the peat. In addition, results suggested that the desorption efficiency decreased with an increase in the adsorbed metal concentration. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801022p

Green recovery of gold through biosorption, biocrystallization, and pyro - crystallization / M. Sathishkumar in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

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Removal of Cr(VI) ions by spent tea and coffee dusts / Syam K. Prabhakaran in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

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