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Iron and copper recovery/removal from industrial wastes / Archana Agrawal in Industrial & engineering chemistry research, Vol. 48 N° 13 (Juillet 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6145–6161 Titre : Iron and copper recovery/removal from industrial wastes : a review Type de document : texte imprimé Auteurs : Archana Agrawal, Auteur ; S. Kumari, Auteur ; K.K. Sahu, Auteur Année de publication : 2009 Article en page(s) : pp. 6145–6161 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Steel  sheets  Iron  oxide  scale  generates  Waste  sulfate/chloride  pickle  liquor Résumé : Surface finishing of steel sheets and strips for the removal of iron oxide scale generates a huge amount of waste sulfate/chloride pickle liquor. Similarly large quantity of bleed stream is generated in the electrolysis industries due to the build up of acidity and metal impurity. The nature of the waste generated has become complex and hazardous in nature. Their impacts on ecological bodies are noticeable due to their toxic nature which is an alarming issue to the environmentalist. Hence, their treatment before disposal is mandatory. With the increasing demand for metals in industry and the depletion of land based resources, the focus of the research community is on the development of new approaches for the recovery of metal values from waste and recycle the water back to the system or dispose of it safely. This paper is a critical review on the waste streams generated from iron and steel industries and copper electrorefining industries. Various aspects on the metal value recovery from these wastes are being dealt with. The main focus is on iron recovery from waste pickle liquor and copper recovery from copper electroplating/electrorefining units by solvent extraction methods. Various solvents used for metal extraction are discussed here. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900135u [article] Iron and copper recovery/removal from industrial wastes : a review [texte imprimé] / Archana Agrawal, Auteur ; S. Kumari, Auteur ; K.K. Sahu, Auteur . - 2009 . - pp. 6145–6161. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6145–6161 Mots-clés : Steel  sheets  Iron  oxide  scale  generates  Waste  sulfate/chloride  pickle  liquor Résumé : Surface finishing of steel sheets and strips for the removal of iron oxide scale generates a huge amount of waste sulfate/chloride pickle liquor. Similarly large quantity of bleed stream is generated in the electrolysis industries due to the build up of acidity and metal impurity. The nature of the waste generated has become complex and hazardous in nature. Their impacts on ecological bodies are noticeable due to their toxic nature which is an alarming issue to the environmentalist. Hence, their treatment before disposal is mandatory. With the increasing demand for metals in industry and the depletion of land based resources, the focus of the research community is on the development of new approaches for the recovery of metal values from waste and recycle the water back to the system or dispose of it safely. This paper is a critical review on the waste streams generated from iron and steel industries and copper electrorefining industries. Various aspects on the metal value recovery from these wastes are being dealt with. The main focus is on iron recovery from waste pickle liquor and copper recovery from copper electroplating/electrorefining units by solvent extraction methods. Various solvents used for metal extraction are discussed here. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900135u

Phase separation mediated devitrification of Al88Y7Fe5 glasses / K.K. Sahu in Acta materialia, Vol. 58 N° 12 (Juillet 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 12 (Juillet 2010) . - pp. 4199–4206 Titre : Phase separation mediated devitrification of Al88Y7Fe5 glasses Type de document : texte imprimé Auteurs : K.K. Sahu, Auteur ; N.A. Mauro, Auteur ; L. Longstreth-Spoor, Auteur Année de publication : 2011 Article en page(s) : pp. 4199–4206 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Coarsening  Aluminum  alloys  Phase  separation  Nucleation  and  growth  Metallic  glass Résumé : The mechanisms responsible for the nanoscale devitrification of Al-based metallic glasses are unclear. A particularly well-studied case is Al88Y7Fe5, where non-isothermal differential scanning calorimetry (DSC) measurements show an exothermic peak that is consistent with glass devitrification to α-Al, but with no glass transition. Additionally, isothermal DSC studies show a monotonic decrease in enthalpy release with annealing, a feature generally taken to indicate grain coarsening. The results of coordinated DSC, bright field transmission electron microscopy, in situ electrical resistivity and atom probe tomography (APT) studies of Al88Y7Fe5 support a nucleation/growth-based crystallization process. The APT data indicate the presence of sub-nanometer pure Al zones and coarser scale (separation distance ∼74–126 nm) Al-rich regions in the glass. The pure Al zones dispersed in the Al-rich regions appear to catalyze α-Al nucleation, explaining the high nucleation rates. The solute-rich regions between the Al-rich regions inhibit long-range diffusion, explaining the low growth rates. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S135964541000217X [article] Phase separation mediated devitrification of Al88Y7Fe5 glasses [texte imprimé] / K.K. Sahu, Auteur ; N.A. Mauro, Auteur ; L. Longstreth-Spoor, Auteur . - 2011 . - pp. 4199–4206. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 12 (Juillet 2010) . - pp. 4199–4206 Mots-clés : Coarsening  Aluminum  alloys  Phase  separation  Nucleation  and  growth  Metallic  glass Résumé : The mechanisms responsible for the nanoscale devitrification of Al-based metallic glasses are unclear. A particularly well-studied case is Al88Y7Fe5, where non-isothermal differential scanning calorimetry (DSC) measurements show an exothermic peak that is consistent with glass devitrification to α-Al, but with no glass transition. Additionally, isothermal DSC studies show a monotonic decrease in enthalpy release with annealing, a feature generally taken to indicate grain coarsening. The results of coordinated DSC, bright field transmission electron microscopy, in situ electrical resistivity and atom probe tomography (APT) studies of Al88Y7Fe5 support a nucleation/growth-based crystallization process. The APT data indicate the presence of sub-nanometer pure Al zones and coarser scale (separation distance ∼74–126 nm) Al-rich regions in the glass. The pure Al zones dispersed in the Al-rich regions appear to catalyze α-Al nucleation, explaining the high nucleation rates. The solute-rich regions between the Al-rich regions inhibit long-range diffusion, explaining the low growth rates. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S135964541000217X