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Dive into the research topics where Valter José Fernandes Junior is active.

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Featured researches published by Valter José Fernandes Junior.


Química Nova | 2012

Iodeto de potássio suportado em peneiras moleculares mesoporosas (SBA-15 e MCM-41) como catalisador básico para síntese de biodiesel

Luzia P. F. C. Galvão; Marcela N. Barbosa; Antonio S. Araujo; Valter José Fernandes Junior; Anne Gabriela Dias Santos; Geraldo E. Luz

Iodide potassium incorporated on mesoporous molecular sieves (SBA-15 and MCM-41) was used as heterogeneous catalysts in the transesterification of sunflower oil under different conditions of reaction time and ratio catalyst/oil (w/w). The results have showed that the system supported in SBA-15 has been more active than the supported in MCM-41, promoting a conversion to methyl esters of 84.98%.


Química Nova | 2012

Caracterização de resíduo sólido formado em biodiesel de sebo bovino

Valter José Fernandes Junior; Antônio de S. Araújo; Fábio da Silva Vinhado; Paulo Roberto Pivesso

The nature of the solid residue formed in beef tallow biodiesel from two commercial producers in Brazil was determined by comparative analytical techniques, namely, gas chromatography with flame ionization detector (GC-FID) and thermogravimetry (TG). Pure monopalmitin and monostearin were used as reference standards for both methodologies. Analyses were carried out before and after filtration of the solids formed, which allowed the observation that the formation of precipitate reduced the levels of monoglycerides in the beef tallow biodiesel. The chromatographic and thermogravimetric results confirmed the nature of the residue as saturated monoglycerides, predominantly monostearin and monopalmitin.


Petroleum Science and Technology | 2017

Kinetic study on the thermal degradation of heavy oil in presence of SBA-15 containing aluminum and cerium

Larissa Cicianny Luz Ferreira de Araújo; Taisa Cristine de Moura Dantas; Aruzza Mabel de Morais Araújo; Amanda Duarte Gondim; Valter José Fernandes Junior; Antonio S. Araujo

ABSTRACT In research for materials that can be applied in processing heavy oil (petroleum), this work proposes to synthesize mesoporous heterogeneous catalysts, type SBA-15, with the addition of cerium metal and aluminum. These catalysts were characterized by X-ray diffraction, scanning electron micrographs coupled to energy dispersive spectrometry, spectroscopy in the infrared region by Fourier transform, N2 adsorption and desorption and thermal analysis-thermogravimetry. Thermal tests were performed to evaluate the thermal and catalytic degradation process with a sample of heavy oil (°API = 14). Through the non-isothermal kinetic model of Ozawa Flynn Wall (OFW) some parameters for determining the apparent activation energy of decomposition were obtained. The petroleum with 12% of Ce5Al50SBA-15 showed a catalytic activity for this material. It has been seen that there was a decrease in the Ea in model free of the order from 89.0 to 104.9 kJ mol−1 in α = 50% ± 10%, and it was repeated from the first percentage until the last showing performance of Ce5Al50SBA-15 as a catalyst.


Revista Virtual de Química | 2015

Tertiary Recycling of Poly(ethylene terephthalate) Aimed at Obtaining Chemicals and Fuels: A Review

Aneliése Lunguinho Figueiredo; Ana Paula de Melo Alves; Valter José Fernandes Junior; Antonio S. Araujo

Plastics have been an indispensable material in the life of humanity. However, these polymers have a slow degradation process that can lead to contamination of soil, air and water when they are not properly allocated. Since the poly (ethylene terephthalate) PET is one of the most commonly consumed thermoplastic resins in Brazil and with a short time of use, it is normal to find it being discarded in landfills, streets, lakes and garbage dumps. Consequently, the recycling of plastic waste is an alternative for avoiding environmental and social problems. In this paper we describe the recycling methods for reuse of plastic waste, mainly the tertiary recycling of PET using the pyrolysis process. Tertiary recycling pyrolysis – of PET is important because it reduces costs of pre-treatment, collection and selection, and allows the obtaining of both a combustible substance and chemicals used for the obtaining of the polymer which gave it origin or even a new polymer, thus eliminating the risk of using recycled PET for packaging foods, beverages and pharmaceuticals.


Journal of Thermal Analysis and Calorimetry | 2011

Comparative study of oxidative stability of sunflower and cotton biodiesel through P-DSC

Luzia P. F. C. Galvão; Anne G. D. Santos; Amanda Duarte Gondim; Marcela N. Barbosa; Antonio S. Araujo; Luiz Di Souza; Valter José Fernandes Junior


Revista Virtual de Química | 2015

Reciclagem Terciária do Poli(etileno tereftalato) Visando a Obtenção de Produtos Químicos e Combustível: Uma Revisão

Aneliése Lunguinho Figueiredo; Ana P. M. Alves; Valter José Fernandes Junior; Antonio S. Araujo


Thermochimica Acta | 2018

Catalytic pyrolysis of glycerol in the presence of Nickel (II) Schiff base complex supported in SBA-15: Kinetic and products (TG-FTIR and PY-CG/MS)

Danielle de OliveiraMaia; Alanna Martinna de SouzaChagas; Aruzza Mabel de Morais Araújo; Antonio Vicente de Mendonça Júnior; Isabelle Mariane de Lima Ferreira; Francisco das Chagas Dantas de Lemos; Antonio S. Araujo; Valter José Fernandes Junior; Amanda Duarte Gondim


UNOPAR Científica Ciências Exatas e Tecnológicas | 2015

Formação e Caracterização de Goma Gasolina Brasileira

Marcílio dos Santos Tavares; Thiago Chellappa; Antonio S. Araujo; Valter José Fernandes Junior


Archive | 2014

STUDY OF OXIDATIVE STABILITY OF BIODIESEL OF THE BLENDS SUNFLOWER/CASTOR OIL OBTAINED BY ETHYLIC ROUTE THROUGH PDSC

Amanda Duarte Gondim; Patrícia F. Carvalho Galvão; Raul Rosenhaim; Valter José Fernandes Junior


Anais do Congresso Brasileiro de Engenharia Química | 2014

Estudo cinético de decomposição térmica do óleo de girassol suportado em material mesoporoso.

Aruzza Mabel de Morais Araújo; Antonio S. Araujo; Valter José Fernandes Junior; Luiz Di Souza

Collaboration


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Antonio S. Araujo

Federal University of Rio Grande do Norte

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Amanda Duarte Gondim

Federal University of Rio Grande do Norte

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Aruzza Mabel de Morais Araújo

Federal University of Rio Grande do Norte

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Aneliése Lunguinho Figueiredo

Federal University of Rio Grande do Norte

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Luzia P. F. C. Galvão

Federal University of Rio Grande do Norte

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Marcela N. Barbosa

Federal University of Rio Grande do Norte

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Luiz Di Souza

University of Rio Grande

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Ana Catarina Fernandes Coriolano

Federal University of Rio Grande do Norte

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Ana P. M. Alves

Federal University of Rio Grande do Norte

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Ana Paula de Melo Alves

Federal University of Paraíba

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