The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform
Rodrigo Navia - One of the best experts on this subject based on the ideXlab platform.
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Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production
Bioresource technology, 2015Co-Authors: C Urrutia, Naiane Sangaletti-gerhard, M. Cea, A Suazo, A Aliberti, Rodrigo NaviaAbstract:Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and Enzymatic Catalysts. The results indicate that both Catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid Catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while Enzymatic Catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and Enzymatic Catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid Catalyst.
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In situ biodiesel production from greasy sewage sludge using acid and Enzymatic Catalysts
Bioresource technology, 2014Co-Authors: Naiane Sangaletti-gerhard, M. Cea, Vicky Risco, Rodrigo NaviaAbstract:This study proposes to select the most appropriate sewage sludge (greasy, primary and secondary) for in situ transesterification and to compare the technical, economic and energetic performance of an Enzymatic Catalyst (Novozym®435) with sulfuric acid. Greasy sludge was selected as feedstock for biodiesel production due to its high lipid content (44.4%) and low unsaponifiable matter. Maximum methyl esters yield (61%) was reached when processing the wet sludge using sulfuric acid as Catalyst and n-hexane, followed by dried-greasy sludge catalyzed by Novozym®435 (57% methyl esters). Considering the economic point of view, the process using acid Catalyst was more favorable compared to Novozym®435 Catalyst due to the high cost of lipase. In general, greasy sludge (wet or dried) showed high potential to produce biodiesel. However, further technical adjustments are needed to make biodiesel production by in situ transesterification using acid and Enzymatic Catalyst feasible.
Naiane Sangaletti-gerhard - One of the best experts on this subject based on the ideXlab platform.
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Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production
Bioresource technology, 2015Co-Authors: C Urrutia, Naiane Sangaletti-gerhard, M. Cea, A Suazo, A Aliberti, Rodrigo NaviaAbstract:Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and Enzymatic Catalysts. The results indicate that both Catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid Catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while Enzymatic Catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and Enzymatic Catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid Catalyst.
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In situ biodiesel production from greasy sewage sludge using acid and Enzymatic Catalysts
Bioresource technology, 2014Co-Authors: Naiane Sangaletti-gerhard, M. Cea, Vicky Risco, Rodrigo NaviaAbstract:This study proposes to select the most appropriate sewage sludge (greasy, primary and secondary) for in situ transesterification and to compare the technical, economic and energetic performance of an Enzymatic Catalyst (Novozym®435) with sulfuric acid. Greasy sludge was selected as feedstock for biodiesel production due to its high lipid content (44.4%) and low unsaponifiable matter. Maximum methyl esters yield (61%) was reached when processing the wet sludge using sulfuric acid as Catalyst and n-hexane, followed by dried-greasy sludge catalyzed by Novozym®435 (57% methyl esters). Considering the economic point of view, the process using acid Catalyst was more favorable compared to Novozym®435 Catalyst due to the high cost of lipase. In general, greasy sludge (wet or dried) showed high potential to produce biodiesel. However, further technical adjustments are needed to make biodiesel production by in situ transesterification using acid and Enzymatic Catalyst feasible.
M. Cea - One of the best experts on this subject based on the ideXlab platform.
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Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production
Bioresource technology, 2015Co-Authors: C Urrutia, Naiane Sangaletti-gerhard, M. Cea, A Suazo, A Aliberti, Rodrigo NaviaAbstract:Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and Enzymatic Catalysts. The results indicate that both Catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid Catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while Enzymatic Catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and Enzymatic Catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid Catalyst.
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In situ biodiesel production from greasy sewage sludge using acid and Enzymatic Catalysts
Bioresource technology, 2014Co-Authors: Naiane Sangaletti-gerhard, M. Cea, Vicky Risco, Rodrigo NaviaAbstract:This study proposes to select the most appropriate sewage sludge (greasy, primary and secondary) for in situ transesterification and to compare the technical, economic and energetic performance of an Enzymatic Catalyst (Novozym®435) with sulfuric acid. Greasy sludge was selected as feedstock for biodiesel production due to its high lipid content (44.4%) and low unsaponifiable matter. Maximum methyl esters yield (61%) was reached when processing the wet sludge using sulfuric acid as Catalyst and n-hexane, followed by dried-greasy sludge catalyzed by Novozym®435 (57% methyl esters). Considering the economic point of view, the process using acid Catalyst was more favorable compared to Novozym®435 Catalyst due to the high cost of lipase. In general, greasy sludge (wet or dried) showed high potential to produce biodiesel. However, further technical adjustments are needed to make biodiesel production by in situ transesterification using acid and Enzymatic Catalyst feasible.
C Urrutia - One of the best experts on this subject based on the ideXlab platform.
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Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production
Bioresource technology, 2015Co-Authors: C Urrutia, Naiane Sangaletti-gerhard, M. Cea, A Suazo, A Aliberti, Rodrigo NaviaAbstract:Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and Enzymatic Catalysts. The results indicate that both Catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid Catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while Enzymatic Catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and Enzymatic Catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid Catalyst.
Georg Fieg - One of the best experts on this subject based on the ideXlab platform.
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scale and causes of Catalyst activity loss in Enzymatic catalyzed reactive distillation
Chemical Engineering Science, 2018Co-Authors: Torben Egger, Lisa S Egger, Georg FiegAbstract:Abstract Continuous Enzymatic catalyzed reactive distillation (eRD) is a new process that can reduce product inhibition and the need for additional purification steps. However, the Enzymatic Catalyst is exposed to markedly different conditions than in conventional processes. The enzyme stability, a crucial cost factor, has not been investigated for the application in an eRD and the underlying mechanisms for Catalyst deactivation are still unknown. This article presents for the first time a comprehensive study on the scale and causes of enzyme activity reduction in eRD processes. Pilot plant experiments with the transesterification of butyl acetate with hexanol catalyzed by Novozyme 435 confirm the existence of a process window with high reaction rates and low activity loss. The remaining activity after 320 h of operation is investigated in each reactive packing, leading to a new found cause of activity reduction that has so far not been considered for Enzymatic catalyzed reactive distillation. The results allow for a better design and operation of eRD processes and the development of enzyme immobilisates that cater to the specific needs of integrated operation.