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Methyl ester production from sunflower and waste cooking oils using alkali - doped metal oxide catalysts / Georgios Karavalakis in Industrial & engineering chemistry research, Vol. 49 N° 23 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp.12168–12172 Titre : Methyl ester production from sunflower and waste cooking oils using alkali - doped metal oxide catalysts Type de document : texte imprimé Auteurs : Georgios Karavalakis, Auteur ; Georgios Anastopoulos, Auteur ; Stamos Stournas, Auteur Année de publication : 2011 Article en page(s) : pp.12168–12172 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Methyl  ester  Metal  oxide  catalysts Résumé : The purpose of this study was to investigate a series of alkali-doped metal oxide catalysts for their activity in the transesterification of sunflower oil and waste cooking oil with methanol. The metal oxides used as supports were Al2O3 and ZnO loaded with KHCO3 and KNO3, respectively, at various concentrations and calcined at different temperatures. These catalysts appeared to be promising candidates to replace homogeneous catalysts for biodiesel production as the reaction times and catalyst amount are low enough in order to achieve high ester yields. In most cases, the increase in loading concentration favorably influenced oil conversion. On the other hand, at calcination temperatures above 750 °C, a noticeable drop in biodiesel yield was observed which may be ascribed to decomposition effects of the active sites. In general, the use of sunflower oil resulted in higher ester yields when compared to waste cooking oil which was characterized by a high amount of free fatty acids and moisture. Biodiesel ester content was also strongly related with catalyst amount, methanol to oil molar ratio, reaction time, and catalyst reusability. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101270e [article] Methyl ester production from sunflower and waste cooking oils using alkali - doped metal oxide catalysts [texte imprimé] / Georgios Karavalakis, Auteur ; Georgios Anastopoulos, Auteur ; Stamos Stournas, Auteur . - 2011 . - pp.12168–12172. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp.12168–12172 Mots-clés : Methyl  ester  Metal  oxide  catalysts Résumé : The purpose of this study was to investigate a series of alkali-doped metal oxide catalysts for their activity in the transesterification of sunflower oil and waste cooking oil with methanol. The metal oxides used as supports were Al2O3 and ZnO loaded with KHCO3 and KNO3, respectively, at various concentrations and calcined at different temperatures. These catalysts appeared to be promising candidates to replace homogeneous catalysts for biodiesel production as the reaction times and catalyst amount are low enough in order to achieve high ester yields. In most cases, the increase in loading concentration favorably influenced oil conversion. On the other hand, at calcination temperatures above 750 °C, a noticeable drop in biodiesel yield was observed which may be ascribed to decomposition effects of the active sites. In general, the use of sunflower oil resulted in higher ester yields when compared to waste cooking oil which was characterized by a high amount of free fatty acids and moisture. Biodiesel ester content was also strongly related with catalyst amount, methanol to oil molar ratio, reaction time, and catalyst reusability. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101270e