Investigation of the pore blockage of a Brazilian dolomite during the sulfation reaction

Autor(es)

Avila, Ivonete ^{[1, 2]} ; Crnkovic, Paula M. ^{[1, 3]} ; Milioli, Fernando E. ^[1] ; Luo, Kai H. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Grp Thermal & Fluids Engn, Sch Engn Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Southampton, Energy Technol Res Grp, Sch Engn Sci, Southampton SO17 1BJ, Hants - England

^[3] Sao Paulo State Univ, Inst Chem, BR-14800900 Araraquara - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Applied Surface Science; v. 258, n. 8, p. 3532-3539, FEB 1 2012.
• Citações Web of Science: 6

Resumo

The influence of the temperature and reaction time on the sulfation process of a dolomite is investigated in this paper. The sulfation effectiveness was evaluated and correlated with changes in the physical characteristics of a Brazilian dolomite during the reactive process. Calcination and sulfation experiments were performed under isothermal conditions for dolomite samples with average particle sizes of 545 mu m at temperatures of 750 degrees C, 850 degrees C and 950 degrees C at different times of sulfation. Thermogravimetric tests were applied to establish the reactivity variation of the dolomite in function of the time in the sulfation reaction and evaluate the methodology of the samples preparation. Porosimetry tests were performed to study the pore blockage of dolomite during the sulfation reaction. The highest values of BET surface area were 25.55 m(2)/g, 29.55 m(2)/g and 12.62 m(2)/g for calcined samples and after their sulfation processes, conversions of 51.5%, 61.9% and 42.8% were obtained at 750 degrees C, 850 degrees C and 950 degrees C, respectively. Considering the process as a whole, the best fit was provided by a first-order exponential decay equation. Moreover, the results have shown that it is possible to quantify the decreasing in the dolomite reactivity for sulfur dioxide sorption and understand the changes in the behavior of the sulfation process of limestones when applied to technologies, as fluidized bed combustor, in which sulfur dioxide is present. (C) 2011 Elsevier B. V. All rights reserved. (AU)

• Processo FAPESP: 08/54062-9 - Correlação da efetividade de reação com a evolução da estrutura física de calcários na sulfatação
• Beneficiário: Ivonete Ávila
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/11321-7 - Estudo do Comportamento do Decaimento da Capacidade de Sorção de CO2 por Calcários aplicado à Tecnologia de Sequestro de Carbono
• Beneficiário: Ivonete Ávila
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado