Banca de QUALIFICAÇÃO: HERBET LIMA OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : HERBET LIMA OLIVEIRA
DATE: 09/05/2023
TIME: 14:00
LOCAL: VIRTUAL
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: 75
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Tecnologia Química
SPECIALTY: Tratamentos e Aproveitamento de Rejeitos
SUMMARY:

For green hydrogen production, electrochemical oxidation (EO) was performed on a Nb/BDD anode at four current densities (7.5, 15, 45, and 60 mA cm^-2), while a stainless steel (SS) cathode was utilized. For 150 min, the tests were carried out in a flow reactor with a mass transfer coefficient of 5.11×10^-5 (m s^-1). EO of washing machine effluent can occur at lower overpotentials than those required for O₂ evolution, which leads to potentially lower-voltage electrolyze operations that could lower the energy requirements for electrolytic production of H₂. In addition, the effect of the supporting electrolyte (0.1 mol L^-1 Na₂SO₄ and 0.1 mol L^-1 H₂SO₄) was studied to determine the best conditions for being electrolyzed with the target to produce high-value products (carboxylic acids and green hydrogen). The production of carboxylic acids was monitored over time for the different conditions tested, and it was observed that a selective production of carboxylic acid was occurring, reaching yields in the production of acetic acid and oxalic acid as high as 11.7%, which opens the possibility of further studies about the application of the electro-refinery concept for other wastes. An important advantage of hybrid electrolysis is the more favorable thermodynamic cost of OOR vs. OER when using organic substrates. The technology proposed here uses a photovoltaic array as an energy source to drive the operation of the designed PEM-type cell, establishing a promising, efficient, and sustainable alternative to produce green hydrogen.

COMMITTEE MEMBERS:
Interna - 2275848 - ELISAMA VIEIRA DOS SANTOS
Externo ao Programa - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE - UFRNExterno à Instituição - JOSÉ EUDES LIMA SANTOS - UNESP