STUDY ON THERMAL ACTIVATION OF BRAZILIAN SERPENTINE APPLIED IN CO2 SEQUESTRATION PROCESS
Vitor de Oliveira Facio1; Ivonete Ávila1; Gretta Larisa Aurora Arce Ferrufino2; Kely Regina Maximo Vieira1; João Andrade Carvalho Júnior3; Carlos Manuel Romero Luna3; Turibio Gomes Soares Neto2; José Carlos Santos2
1 Faculty of Engineering at Guaratinguetá; 2 National Institute for Space Research; 3 UNESP- Faculty of Engineering at Guaratinguetá
doi:10.20906/CPS/COB-2015-1058
Resumo
Climate change is attributed to the use of fossil fuels for power generation. This is due to large amounts of carbon dioxide (CO2) injected into the atmosphere, product of its combustion. The power generation using fossil fuels is a mature and economically viable technology. Therefore, as long as there is not an increase of renewable energy use in the coming years, fossil fuels will continue to be the basis of global energy matrix. Mineral carbonation (MC) is one of carbon capture and sequestration (CCS) technologies that could allow the continued use of fossil fuels in a sustainable way. MC is a process in which carbon dioxide (CO2) reacts with materials containing high concentration of calcium and magnesium in order to produce carbonates, which are environmentally stable. Brazil has a large availability of silicate minerals, which are materials with a potential use on mineral carbonation processes. Actually, MC research is receiving more attention, still it faces challenges, such as the increase of the carbonation reaction kinetics. This could be achieved using thermal activation as pre-treatment for the material. However, the energy consumption must be evaluated since this technology could be invalidated by its technical and economical aspects. The thermal activation consists in heating the material to reduce the concentration of hidroxyl ions (OH-) on its structure. This process is known as dehydroxylation, which can increase the efficiency of the MC. This study evaluated the thermal behavior of dehydroxylation process of two serpentine (S) rocks named S-GO (from Goiás state) and S-MG (from Minas Gerais state). Thermal analysis techniques (TG/DTA/DSC) results indicate that S-GO have higher amount of OH- this difference is related to the mineralogical structure of S-GO which contains serpentine (Mg3Si2O5(OH)4) and also brucite (Mg(OH)2). The characteristic of brucite is to have drhydroxilation temperatures around 300-500°C. On the other hand, according to the literature around 20% of dehydroxylation of the mat
Palavras-chave: Thermal activation; Mineral carbonation; Thermal analysis; Serpentinite; Carbon dioxide