Banca de DEFESA: EDILSON DO VALE JÚNIOR

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : EDILSON DO VALE JÚNIOR
DATE: 10/12/2021
TIME: 09:00
LOCAL: VIDEOCONFERÊNCIA
TITLE:

APPLICATION OF ELECTROCHEMICAL AND ELECTROANALYTICAL METHODS IN THE TREATMENT OF WASTEWATERS

KEY WORDS:

Waste water treatment; dyes; electrochemical oxidation; peroxy-coagulation; differential pulse voltammetry.

PAGES: 105
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Eletroquímica
SUMMARY:

The application of electrochemical technologies in remediation of wastewater has been extensively studied due to the promising results achieved. These technologies are mainly based on the generation of species with high oxidation power, which in turn are responsible for the degradation and mineralization of organic compounds. In this work, the application of some of these methodologies in the treatment of synthetic contaminated water was studied, in addition to the use of electroanalytical technologies in the detection and quantification of these compounds. The results achieved are presented in two distinct chapters. In the first chapter, peroxycoagulation (PC) was used to treat a synthetic effluent of methyl orange (MO), an azo dye, studying the effects of different parameters including initial pH, current density (j), initial concentration of dye and electrolyte support. In addition, PC performance has been compared to other advanced electrochemical processes, under similar experimental conditions. The results indicate that the kinetic decay of the MO increases in the following order: electrocoagulation (EC) < electrochemical oxidation (EO) with electrogenerated H₂O₂ < PC < electro-Fenton (EF). This behavior is attributed to the highly oxidizing character of the homogeneous ●OH radicals generated by the EF and PC processes. Energy consumption was about 0.06 kWh gCOD^-1, 0.09 kWh gCOD^-1, 0.7 kWh gCOD^-1 and 0.1 kWh gCOD^-1 were achieved for PC, EF, EO-H₂O₂ and EC, respectively. PC thus appears as a promising and competitive alternative for the decontamination of wastewater. In the second chapter, the detection and quantification of p-benzoquinone (BQ) was performed using the differential pulse voltammetry (DPV) technique with a diamond film sensor, in addition to BQ degradation by anodic oxidation. A series of electrochemical galvanostatic oxidation experiments with 130 mL of BQ solution was carried out in order to understand the effect of current density, pollutant concentration and initial pH using different electrolytes with similar conductivity. The ideal operating conditions were achieved in 33.3 mA cm^-2, 100 mg L^-1 of BQ at pH 5.0 with 50 mM Na₂SO₄. In addition, the evolution of short-chain carboxylic acids in this test was followed over time to suggest a possible degradation route. Demonstrating the efficiency of electrochemical technology in the degradation and evaluation of treatment.

BANKING MEMBERS:
Presidente - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Externa ao Programa - 2275848 - ELISAMA VIEIRA DOS SANTOS
Externa à Instituição - ALINE MARIA SALES SOLANO - IFRN
Externa à Instituição - DANYELLE MEDEIROS DE ARAUJO - UERN
Externo à Instituição - MARCO ANTONIO QUIROZ ALFARO - udlap