Surplus of glycerol production from the biodiesel industry has led to the search for glycerol conversion routes, the most common of which are dehydration and oxidative dehydration. Vanadium and molybdenum oxides were supported on γ-Al 2 O 3 and their properties were analyzed through several characterization techniques, showing that the acidity increases after addition of oxides and that in the catalyst with vanadium and molybdenum there is decrease in the band referring to V 5+ , responsible for sequential oxidation to CO 2 . The effect of the metal oxides on catalytic activity and stability during oxidative dehydration of glycerol to acrolein was investigated and correlated with chemical composition, acidity, and textural properties. Moreover, the global reaction, turnover frequency (TOF), and activation energy were determined. Catalyst performance and stability were found to depend on acidity and the supported metal with larger residence times (W/F) favored acrolein formation over CO x . In addition, metal oxides decreased catalyst deactivation via coke oxidation.

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The convective drying process of cherry and grape tomatoes for dried tomato production was studied taking into account operational and sensorial aspects. The tomatoes were physicochemical characterized and dried at three air temperatures in a drying chamber. Thus, it was possible to the determinate the physicochemical characteristics, drying kinetics, thickness shrinkage, effective moisture diffusivity and activation energy. The effects of tomato type (cherry and grape), air temperature (60°C and 80°C), and final moisture (25% and 35% w.b.) were sensory evaluated utilizing a factorial experiment. The drying kinetics demonstrated that the drying processes occurred preferably in the falling rate-drying periods. The grape tomato showed a faster drying process, which was attributed to its higher surface area and also its internal structure. The sensory evaluation demonstrated that the cherry tomato, dried at lower air temperatures, resulted in better sensorial characteristics and higher purchasing intention, whereas the final moisture had no effect.

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Elaborado por Maurício Amormino Júnior-CRB6/2422 O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. 2019 Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.