Banca de DEFESA: HERBET LIMA OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : HERBET LIMA OLIVEIRA
DATE: 26/02/2024
TIME: 09:00
LOCAL: Auditório do NUPPRAR
TITLE:

Hydrogen fuel generation from electrochemical wastewater treatment: a new arising concept for energy source

KEY WORDS:

Green hydrogen, electro-refinery, washing machine effluents, high value-added products, circular economy.

PAGES: 125
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Tecnologia Química
SPECIALTY: Tratamentos e Aproveitamento de Rejeitos
SUMMARY:

With the increase in population, we see new challenges emerging in different sectors of society. This changing scenario gave rise to the 2030 Agenda, which addresses the objectives of sustainable development. Issues such as the increase in domestic effluents, growing food demands and the consequent increase in industrial waste, including various biomasses, as well as the use of fossil fuels, stand out as important environmental challenges that require more sustainable solutions for the future. In this context, the electrorefinery appears as an attractive proposal to face these problems. By employing clean energy, it makes it possible to convert materials considered waste into value-added products. Therefore, this work aims to transform a real domestic effluent, in this case, the washing water from a washing machine, and an industrial residue, the liquid from the shell of cashew nuts, into value-added products, such as acids carboxylic acids, while simultaneously cogenerating green hydrogen. Cells divided by polymeric electrolytic membranes, types PEM and AEM, were used, with BDD/Nb electrodes as anode and Ni-Fe stainless steel mesh as cathode. In the treatment of washing machine effluent, two different electrolytes were tested (H2SO4 0.1 mol L-1 and Na2SO4 0.1 mol L-1), also varying the current densities. The results reveal the production of products with added value, especially carboxylic acids, with emphasis on selectivity to acetic acid, reaching 45.7 mg L-1. Furthermore, we observed the generation of green H2, with volumes of approximately 0.8 L. When using the liquid from cashew nut shells, different conditions were explored, such as current density, concentration and nature of the electrolyte (NaOH 0.125, 1.0 and 2.0 mol L-1 and Na2SO4 0.05 mol L-1), and substrate concentration. It was found that all variables influence the production of carboxylic acids and the energy efficiency of green H2, with the substrate concentration being the most significant variable in the production of acids and current density in that of green H2. As the substrate concentration increases, it was possible to achieve acetic acid production rates of 565.4 mg L-1, and at higher current densities, green H2 volumes of 1.8 L were observed. , the viability of technology based on electrorefinery is evidenced by the selective electrochemical transformation of organic pollutants from waste into value-added products, such as green H2 and carboxylic acids. This advance represents a promising step towards the circular economy, contributing to environmental sustainability.

COMMITTEE MEMBERS:
Presidente - 2275848 - ELISAMA VIEIRA DOS SANTOS
Externo ao Programa - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE - UFRNExterno à Instituição - JOSÉ EUDES LIMA SANTOS - UFRN
Externo à Instituição - MARCO ANTONIO QUIROZ ALFARO - udlap
Externo à Instituição - SALVADOR COTILLAS SORIANO - UCMADRID