Banca de QUALIFICAÇÃO: DENER DA SILVA ALBUQUERQUE

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : DENER DA SILVA ALBUQUERQUE
DATA : 19/07/2019
HORA: 10:00
LOCAL: Auditório do NUPPRAR
TÍTULO:

Copper Titanates and Ferro as Solid Oxygen Conveyors for Use in Combustion Processes with Chemical Recirculation

PALAVRAS-CHAVES:

Oxygen Carriers, CO2 capture, Chemical Looping Combustion (CLC), Iron Titanates and Copper Titanates

PÁGINAS: 90
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Cerâmicos
RESUMO:

The emission of CO2 from the combustion of fossil fuels associated with the growing global demand for energy is a factor that contributes directly to global warming. In the desire to reduce emissions, as well as the severe consequences of this gas, several researchers around the world have developed technologies that minimize these emissions and produce a cleaner CO2, facilitating the process of CO2 capture and storage (CAC). Among the technologies, the Chemical Looping Combustion (CLC) combustion by chemical recirculation process, which promotes the indirect combustion of the fuel through oxygen carriers, produces a free combustion of N2, which avoids the formation of compounds such as NOx and facilitates the capture of CO2 without additional separation costs. Thus, this doctoral thesis aims to synthesize, characterize and test oxygen carriers based on titanates copper and iron for use in combustion processes with chemical looping. Oxygen transporters (TO) were synthesized from stoichiometric calculations by the polymer precursor method (Pechini). The techniques and methodologies used were: X-Ray Fluorescence (XFR), X-Ray Diffraction (XRD), Mössbauer Spectroscopy (EM), Scanning Electron Microscopy (EDS) with EDS, Programmed Temperature Reduction ), reactivity by thermogravimetry, oxygen transport capacity (Roc) and the index rate of the reduction and oxidation cycles. The chemical composition of each iron and copper titanate was obtained by XFR. Through XDR with Rietveld and EM refinement, the main reactive phases were identified as Fe2TiO5 and Fe2O3 for iron titanates and CuO for copper titanate. Through MVE-FEG with EDS analyzed the morphology of the (TO) and the distribution of the active phases by the surface of each one. During the TPR analysis, these active phases were submitted, respectively, to the atmosphere of H2 and later to synthetic air and presented good capacity of reduction and oxidation. Through the consumption of H2 used to reduce each phase, the experimental Roc of the oxygen transporters was calculated. The reactivity of the samples was evaluated by thermogravimetry with methane gas (CH4) for cycles of reduction and oxidation. Due to the structural characteristics and reactivity tests of these materials, it is concluded that both copper titanate has the necessary requirements to be used in chemical looping (CLC) combustion processes.

MEMBROS DA BANCA:
Presidente - 349770 - DULCE MARIA DE ARAUJO MELO
Externa ao Programa - 1979301 - RENATA MARTINS BRAGA
Externo à Instituição - RODOLFO LUIZ BEZERRA DE ARAÚJO MEDEIROS - UFRN
Externo à Instituição - RODRIGO CÉSAR SANTIAGO - UFERSA