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Extraction of nickel from spent catalyst using biodegradable chelating agent EDDS / Garima Chauhan in Industrial & engineering chemistry research, Vol.51 N° 31 (Août 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol.51 N° 31 (Août 2012) . - pp. 10354-10363 Titre : Extraction of nickel from spent catalyst using biodegradable chelating agent EDDS Type de document : texte imprimé Auteurs : Garima Chauhan, Auteur ; Kamal K. Pant, Auteur ; Krishna D. P. Nigam, Auteur Année de publication : 2012 Article en page(s) : pp. 10354-10363 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chelating  agent  Catalyst Résumé : Literature suggests that ethylene-diamine-tetraacetic acid (EDTA) has been proved as a successful chelating agent for the extraction of metals from soils and spent catalysts. EDTA, however, is quite persistent in the environment due to its low biodegradability, thus its use becomes a matter of environmental concern. Therefore, to minimize the potential environmental risks, a new chelating agent [S,S]-ethylene-diamine-disuccinic-acid ([S,S]-EDDS) can be considered as an environmentally benign substitute for EDTA due to its easy biodegradation capability. The present study focuses on the effectiveness of biodegradable chelating agent [S,S]-EDDS for extraction of nickel from the spent catalyst of fertilizer industry. Experiments were carried out in batch mode under reflux conditions and process design parameters were optimized to maximize the extraction efficiency. Ni extraction of 84% was attained at optimum reaction condition in one cycle run. Dechelation of Ni-EDDS complex was performed at pH 5 where more than 96% EDDS was recovered. Results of the present study were compared with the previously studied chelating agent EDTA at optimum reaction conditions reported in literature. It was observed that [S,S]-EDDS requires a narrower pH range as compared to EDTA for chelation-dechelation process. Thus milder reaction conditions were employed for metal extraction using EDDS which is favorable to select the material of construction of equipment, in addition to the added advantage of biodegradability. Kinetic study was also performed for the noncatalyzed extraction process using shrinking core model and the process was found to be diffusion controlled under experimental conditions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26234066 [article] Extraction of nickel from spent catalyst using biodegradable chelating agent EDDS [texte imprimé] / Garima Chauhan, Auteur ; Kamal K. Pant, Auteur ; Krishna D. P. Nigam, Auteur . - 2012 . - pp. 10354-10363. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol.51 N° 31 (Août 2012) . - pp. 10354-10363 Mots-clés : Chelating  agent  Catalyst Résumé : Literature suggests that ethylene-diamine-tetraacetic acid (EDTA) has been proved as a successful chelating agent for the extraction of metals from soils and spent catalysts. EDTA, however, is quite persistent in the environment due to its low biodegradability, thus its use becomes a matter of environmental concern. Therefore, to minimize the potential environmental risks, a new chelating agent [S,S]-ethylene-diamine-disuccinic-acid ([S,S]-EDDS) can be considered as an environmentally benign substitute for EDTA due to its easy biodegradation capability. The present study focuses on the effectiveness of biodegradable chelating agent [S,S]-EDDS for extraction of nickel from the spent catalyst of fertilizer industry. Experiments were carried out in batch mode under reflux conditions and process design parameters were optimized to maximize the extraction efficiency. Ni extraction of 84% was attained at optimum reaction condition in one cycle run. Dechelation of Ni-EDDS complex was performed at pH 5 where more than 96% EDDS was recovered. Results of the present study were compared with the previously studied chelating agent EDTA at optimum reaction conditions reported in literature. It was observed that [S,S]-EDDS requires a narrower pH range as compared to EDTA for chelation-dechelation process. Thus milder reaction conditions were employed for metal extraction using EDDS which is favorable to select the material of construction of equipment, in addition to the added advantage of biodegradability. Kinetic study was also performed for the noncatalyzed extraction process using shrinking core model and the process was found to be diffusion controlled under experimental conditions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26234066

A review on the potential applications of curved geometries in process industry / Subhashini Vashisth in Industrial & engineering chemistry research, Vol. 47 N°10 (Mai 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3291–3337 Titre : A review on the potential applications of curved geometries in process industry Type de document : texte imprimé Auteurs : Subhashini Vashisth, Auteur ; Vimal Kumar, Auteur ; Krishna D. P. Nigam, Auteur Année de publication : 2008 Article en page(s) : p. 3291–3337 Note générale : Bibliogr. p. 3327-3337 Langues : Anglais (eng) Mots-clés : Curved  tubes;  Friction  factor;  Heat  transfer;  Mass  transfer Résumé : The potential industrial applications of curved tubes for single- and two-phase flow are reviewed within the context of physics of flow, trends in the development of technology, and its laboratory to industrial-scale commercialization. Comparison of the performance of curved tube configurations demonstrates its edge over the conventional motionless mixers, heat exchangers, and reactors. Alongside, their respective advantages and limitations are also highlighted. Further, a compendium of the available correlations for single- and two-phase friction factor and heat- and mass-transfer coefficient in curved tubes has also been presented. Key issues regarding the design parameters governing the performance of the curved tubes for mixing and heat- and mass-transfer that impact the research, development, and scale-up or scale-down of such devices are also analyzed. Emerging trends for the development of a new class of curved tubes, namely, inverters and serpentine and chaotic devices are also presented. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701760h [article] A review on the potential applications of curved geometries in process industry [texte imprimé] / Subhashini Vashisth, Auteur ; Vimal Kumar, Auteur ; Krishna D. P. Nigam, Auteur . - 2008 . - p. 3291–3337. Bibliogr. p. 3327-3337 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3291–3337 Mots-clés : Curved  tubes;  Friction  factor;  Heat  transfer;  Mass  transfer Résumé : The potential industrial applications of curved tubes for single- and two-phase flow are reviewed within the context of physics of flow, trends in the development of technology, and its laboratory to industrial-scale commercialization. Comparison of the performance of curved tube configurations demonstrates its edge over the conventional motionless mixers, heat exchangers, and reactors. Alongside, their respective advantages and limitations are also highlighted. Further, a compendium of the available correlations for single- and two-phase friction factor and heat- and mass-transfer coefficient in curved tubes has also been presented. Key issues regarding the design parameters governing the performance of the curved tubes for mixing and heat- and mass-transfer that impact the research, development, and scale-up or scale-down of such devices are also analyzed. Emerging trends for the development of a new class of curved tubes, namely, inverters and serpentine and chaotic devices are also presented. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701760h