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(Reference retrieved automatically from Google Scholar through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Determination of the activation energies of beef tallow and crude glycerin combustion using thermogravimetry

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Author(s):
Crnkovic, Paula Manoel [1, 2] ; Koch, Christoph [3] ; Avila, Ivonete [1] ; Mortari, Daniela Andresa [1] ; Cordoba, Aymer Maturana [1] ; dos Santos, Antonio Moreira [1]
Total Authors: 6
Affiliation:
[1] Univ Sao Paulo, Sao Carlos, SP - Brazil
[2] Paulista State Univ Unesp, Inst Chem, Araraquara - Brazil
[3] Leibniz Univ Hannover, Hannover - Germany
Total Affiliations: 3
Document type: Journal article
Source: BIOMASS & BIOENERGY; v. 44, p. 8-16, 2012.
Web of Science Citations: 26
Abstract

The present study deals with the determination of the activation energy for the thermal decomposition of two renewable fuels crude glycerin and beef tallow. The activation energies were investigated by using a thermogravimetric analyzer (TGA) in the temperature range of 25-600 degrees C in atmosphere of synthetic air. The TG curves of the thermal decomposition process of both samples were divided into several phases and the second, called PH2, was chosen for the kinetic study because it is associated with the combustion ignition. Differential Thermal Analysis (DTA) showed an endothermic event at the PH2 region for the crude glycerin corresponding to devolatilization, while for beef tallow, this step presented an exothermic event, called LTO (low-temperature oxidation), which is correlated with devolatilization followed by combustion. For the entire PH2, activation energy values for crude glycerin were between 90 kJ mol(-1) and 42 kJ mol(-1), while for the beef tallow they ranged from 50 kJ mol(-1) to 113 kJ mol (1). The activation energy values obtained at the pre-ignition stage - conversion between 0 and 0.45 - showed that the crude glycerin with higher values requires an additional energetic support at the start of combustion processes and the beef tallow ignites more easily, presenting lower values. According to the Wolfer's equation, a direct relation between the activation energy and the ignition delay is established and the results of this study provides useful data for the development and design of new combustion chambers and engines when non-traditional fuels are used as feedstock. (C) 2012 Elsevier Ltd. All rights reserved. (AU)

FAPESP's process: 11/00183-2 - Use of thermal analysis and drop tube furnace (DTF) to evaluate the thermal efficiency of mineral coal, sugarcane bagasse and their blends
Grantee:Daniela Andresa Mortari
Support Opportunities: Scholarships in Brazil - Doctorate
FAPESP's process: 11/11321-7 - Study of Decay Behavior of the CO2 Sorption by Limestones applied to the Carbon Sequestration Technology
Grantee:Ivonete Ávila
Support Opportunities: Scholarships in Brazil - Post-Doctoral