Banca de DEFESA: FERNANDO VELCIC MAZIVIERO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : FERNANDO VELCIC MAZIVIERO
DATE: 05/01/2021
TIME: 15:00
LOCAL: Remotamente pelo Google Meet
TITLE:

INFLUENCE OF PROMOTERS ON Ni-X/Al₂O₃ (X= Mn, Mg, Ce and P) CATALYSTS APPLIED IN DRY REFORMING OF METHANE PROCESS.

KEY WORDS:

Dry reforming of methane, syngas, catalytic promoters, Ni/Al₂O₄

PAGES: 81
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SPECIALTY: Físico Química Inorgânica
SUMMARY:

The dry reforming of methane process (RSM) is a technology that uses two of the main greenhouse gases (CH₄ and CO₂) for the production of syngas (H₂ and CO), which has several industrial applications in addition to hydrogen be considered a source of clean and highly efficient energy, giving it high commercial value. Nickel-based catalysts based on alumina were prepared containing the Mg, Mn, Ce and P promoters, chosen due to their different chemical properties. The synthesis method used for the support was microwave assisted combustion where urea was used as fuel for the process in quantities below the stoichiometric point in order to obtain lower crystallinity Al₂O₃ in the gamma phase. The promoters and the active phase were incorporated into the support using the sequential impregnation method via incipient wetness, ending the synthesis stage with heat treatment at a temperature of 550 ° C for three hours. The obtained materials were characterized by X-Ray Diffraction (XRD) to elucidate the phases obtained in each catalyst and to evaluate the influence of the promoters on the material structure, spectroscopy in the infrared region with Fourier transform (FTIR) to prove the presence of phosphorus in the catalyst and evaluate the species it is in, Temperature Programmed  Reduction (TPR) to identify the reducible species present and the reduction profile of the catalysts and in-situ X-Ray Diffraction using a synchrotron radiation source to analyze the variation of the structure during the activation step. The catalytic test was carried out at a temperature of 700 °C with GHSV = 100 L.g^-1.h^-1 for 20 hours and the carbon formed was quantified through thermogravimetric analysis. The results indicated that successive steps of solubilization and calcination resulting from the sequential impregnation method cause structural changes, altering the degree of crystallinity of the Al₂O₃ support in the catalyst with the promoters. In the catalytic stability test, the materials containing Mn promoter obtained the best conversion value due to the presence of MnO₂, which favors parallel reactions of methane decomposition during the RSM process. The catalysts containing phosphorus and cerium produced smaller amounts of coke compared to the standard catalyst due to the interaction of promoters with carbon on the surface of the catalytic sites, in addition to acting on the particle size obtained for the active phase.

BANKING MEMBERS:
Presidente - 349770 - DULCE MARIA DE ARAUJO MELO
Externo à Instituição - GILVAN PEREIRA DE FIGUEREDO - IFMA
Externo à Instituição - RODOLFO LUIZ BEZERRA DE ARAÚJO MEDEIROS - UFRN
Interna - 1308577 - SIBELE BERENICE CASTELLA PERGHER