EAJ - Artigos publicados em periódicos

URI Permanente para esta coleçãohttps://repositorio.ufrn.br/handle/1/2966

Navegar

Agora exibindo 1 - 2 de 2

Catalytic upgrading of Elephant grass (Pennisetum purpureum Schum) pyrolysis vapor using WO3 supported on RHA and RHA-MCM-41
(Elsevier, 2017-01-01) Melo, Marcus Antônio de Freitas; Braga, Renata Martins; Melo, Dulce Maria de Araújo; Vitor Sobrinho, Eledir; Barros, Joana Maria de Farias; Carvalho, Alexandre Fontes Melo de; Fontes, Maria do Socorro Braga; Freitas, Júlio César de Oliveira
Recently, zeolites have been widely applied in catalytic pyrolysis to improve physical and chemical properties of bio-oil to produce energy or to selectively produce chemicals for industry. This study aims to analyze the catalytic pyrolysis products of Elephant Grass (EG) using WO3 catalysts supported on rice husk ash (RHA) silica and RHA-MCM-41, being low cost materials derived from agro industrial waste, and evaluate the catalysts activity in the formation of deoxygenated compounds. Elephant Grass has been shown as a potential energy crop that has fast growth and is easy to cultivate in different countries, including Brazil. Its energetic characterization was evaluated by proximate and ultimate analysis, High Heat Value (HHV), cellulose, hemicellulose and lignin content, chemical ash composition by FRX and bulk density. Pyrolysis analysis was performed at 500 ◦C in a Py-5200 HP-R connected to a GC–MS, and pyrolysis vapors were carried by N2 to a catalytic bed at 400 and 600 ◦C. It was noticed that increasing catalyst temperature promotes cracking reactions leading to increased aromatic content. The main oxygenated pyrolysis products of EG such as phenols, furans, ketones and acetic acid were converted at 600 ◦C using WO3/RHA catalyst into aromatics (benzene, toluene, xylene, styrene), being of high added value for chemical industry. The main influence on aromatics yields could be related to catalytic activity of WO3 promoted by its redox ability and the rise in temperature which favors cracking reactions
Characterization and pyrolysis of Chlorella vulgaris and Arthrospira platensis: potential of bio-oil and chemical production by Py-GC/MS analysis
(Springer Nature, 2017-04-17) Melo, Marcus Antônio de Freitas; Almeida, Hanna Nóbrega; Calixto, Guilherme Quintela; Chagas, Bruna M. E.; Melo, Dulce Maria de Araújo; Resende, Fabio M.; Braga, Renata Martins
Biofuels have been seen as potential sources to meet future energy demand as a renewable and sustainable energy source. Despite the fact that the production technology of first-generation biofuels is consolidated, these biofuels are produced from foods crops such as grains, sugar cane, and vegetable oils competing with food for crop use and agricultural land. In recent years, it was found that microalgae have the potential to provide a viable alternative to fossil fuels as source of biofuels without compromising food supplies or arable land. On this scenario, this paper aims to demonstrate the energetic potential to produce bio-oil and chemicals from microalgae Chlorella vulgaris and Arthrospira platensis. The potential of these biomasses was evaluated in terms of physical-chemical characterization, thermogravimetric analysis, and analytical pyrolysis interfaced with gas chromatograph (Py-GC/MS). The results show that C. vulgaris and A. platensis are biomasses with a high heating value (24.60 and 22.43 MJ/kg) and low ash content, showing a high percentage of volatile matter (72.49 and 79.42%). These characteristics confirm their energetic potential for conversion process through pyrolysis, whereby some important aromatic compounds such as toluene, styrene, and phenol were identified as pyrolysis products, which could turn these microalgae a potential for biofuels and bioproduct production through the pyrolysis

SIGAA

Navegar

Navegando EAJ - Artigos publicados em periódicos por Assunto "Biomass"