Banca de DEFESA: PATRICIA RACHEL FERNANDES DA COSTA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : PATRICIA RACHEL FERNANDES DA COSTA
DATA : 23/11/2018
HORA: 09:00
LOCAL: Auditório do CCET
TÍTULO:

TREATMENT OF REAL EFFLUENTS USING ELECTROCOAGULATION AND ELECTROCHEMICAL OXIDATION

PALAVRAS-CHAVES:

Real effluent, phytotoxicity, cashew nuts, Electrochemistry

PÁGINAS: 150
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Analítica
ESPECIALIDADE: Eletroanalítica
RESUMO:

Industrial growth is a major cause of the excessive pollution and release of chemical waste in water, atmosphere and landfills. Toxic waste, such as lead, chromium and phenols, are considered very aggressive to nature and man and can even lead to death and permanent contamination. The industrial solid waste is distinguished by the large amount generated, where among these residues, a large part is classified as dangerous, that is, class I waste, because they have characteristics such as: flammability, corrosivity, reactivity, toxicity and pathogenicity. The cashew nut processing industry (IBCC) generates a residue rich in phenolic compounds from the process of obtaining cashew nut (ACC) and cashew nut (LCC) liquid. The disposal or reuse of these effluents, without adequate treatment, can cause serious environmental and health problems, as these residues are mostly toxic and refractory to commonly used treatments, requiring the use of more efficient treatment technologies. During the electrochemical oxidation process OH and • Cl are produced which are responsible for the degradation of recalcitrant organic compounds, besides having the advantage of not using chemical agents. The proposal of this thesis was divided into two articles where the first deals with a recirculated BDD-batch reactor is presented, for the first time, to the electrochemical treatment of a real cashew effluent. The results clearly indicated that the addition of external electrolyte and the initial pH change are two factors that do not lead to a significant improvement in the degradation of organic matter when compared to the treatment of the effluent received. On the other hand, an increase in current density promoted a COD removal of up to 89%, after 150 min of oxidation, due to the increase in the generation of strong oxidants. The low production of carboxylic acids was also detected over time. The second article deals with a pioneering sequential process involving electrocoagulation (EC) and electrochemical oxidation (EO) approaches. The performance of the system was analyzed in terms of removal of chemical oxygen demand, by-product evolution, toxicity and energy consumption. Sequential experiments, using EC at 8.33 or 100 mA cm-2 plus EO, enhanced COD removal to 51% and 80%. Phytotoxicity analyzes were performed to evaluate the water quality for reuse in irrigation activities. Based on these results, the sequential experiment with EC by the application of 8.33 mA cm-2 plus EO (0.11 A) was considered the most efficient and feasible to purify the actual effluent from the cashew nut processing.

 

MEMBROS DA BANCA:
Presidente - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Externo ao Programa - 2524058 - DOUGLAS DO NASCIMENTO SILVA
Externo à Instituição - JULIANA PATRICIA SOUZA DUARTE PONTES - IFRN
Externo à Instituição - SUELY SOUZA LEAL DE CASTRO - UERN