Banca de DEFESA: LUCAS RODRIGUES DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LUCAS RODRIGUES DE OLIVEIRA
DATE: 14/02/2023
TIME: 09:00
LOCAL: Programa de Pós-Graduação em Ciência de Materiais
TITLE:

SYNTHESIS OF PALLADIUM NANOCATALYST SUPPORTED ON GRAPHENE DERIVATIVES FOR HYDROGEN PRODUCTION VIA FORMIC ACID DECOMPOSITION

KEY WORDS:

Hydrogen production; Graphene oxide; Palladium nanoparticles; catalysts; Amino acids.

PAGES: 97
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

Hydrogen is considered by many to be the energy vector of the future, capable of playing a significant role in the decarbonization of the world's energy matrix. However, its use still needs to be improved due to the unavailability of more effective and secure storage technologies than commercially available ones. Among the new hydrogen storage and transport technologies under development, organic liquids as molecular hydrogen containers have gained prominence in recent years. In this context, this work aims to develop nanocatalysts based on palladium supported by graphene derivatives and their use in the formic acid (FA) dehydrogenation reaction for hydrogen production. Thus, graphene oxide was previously prepared using the modified Hummers method, followed by functionalization with arginine (GO-ARG) and (3- aminopropyl)triethoxysilane (GO-APTES). These samples were used as supports for palladium nanoparticles originating three catalytic systems, Pd/rGO, Pd/ARG-rGO, and Pd/APTES-rGO, characterized by XRD, FTIR, SEM, and EDS. The results confirmed the obtainment of graphene oxide and the success of the functionalization with arginine and APTES, also indicating that the functionalization provided a better dispersion and control of the size of the palladium nanoparticles later deposited on these supports. Furthermore, according to the data obtained by gas chromatography, the two modified catalysts are 100% selective and completely inhibited the formation of CO. In contrast, the Pd/rGO catalyst showed a larger metallic nanoparticle size, which significantly affected the performance of this system. Thus, among the three evaluated systems, the catalyst modified with arginine presented the best result, producing a total of 78 mL of gas at 45°C (60 minutes of reaction), with an apparent activation energy value of 19.93 Kj.mol-1 and hydrogen production rate equivalent to 65 mL.H2.min-1 .g-1 . In recycling tests, the catalyst showed activity up to the fourth reaction cycle.

COMMITTEE MEMBERS:
Presidente - 1754300 - BRAULIO SILVA BARROS
Interno - 2457389 - EDUARDO PADRON HERNANDEZ
Externo ao Programa - 1810494 - KLEBER GONCALVES BEZERRA ALVES - null