Influence of pH and ozone dose on sulfaquinoxaline ozonation

Autor(es)

Urbano, Vanessa Ribeiro ; Maniero, Milena Guedes ; Perez-Moya, Montserrat ; Guimaraes, Jose Roberto

• Tipo de documento: Artigo Científico
• Fonte: Journal of Environmental Management; v. 195, p. 8-pg., 2017-06-15.

Resumo

Sulfaquinoxaline (SQX) is an antimicrobial of the sulfonamides class. Usually employed in veterinary medicine, this contaminant of emerging concern has been found in superficial and groundwater and its consequences for the environment and human health are not completely known. In this study, SQX (C-0 = 500 mu g L-1,1 L) degradation by an ozonation process at pH 3, 7, and 11 was evaluated. Ozonation was effective in degrading SQX: efficiency exceeding 99% was obtained applying an ozone dose of 2.8 mg L-1 at pH 3. Assays were performed according to a 22 design of experiments (DOE) with star points and three central points for statistical validity. Minimum and maximum levels were set at 3 and 11 for pH, and 0 and 11.5 mg L-1 for applied ozone dose. There was no significant interaction between these variables, and the pH value played the most important role in terms of contaminant degradation. In relation to toxicity, samples ozonated at pH 3 did not inhibit the luminescence of the bacteria, even though different intermediates were formed and identified by mass spectra. At pH 7, inhibition of luminescence remained almost constant (at around 30%) according to ozonation time or ozone dose. However, the hydroxyl radical, the major oxidant at pH 11, was responsible for the formation of toxic intermediates. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 14/06064-3 - EMU concedido no processo 2013/09543-7: cromatógrafo líquido de ultraeficiência com detetores de arranjo de fotodiodos e fluorescência (UPLC-DAD-FLD)
• Beneficiário: Susanne Rath
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 13/04656-8 - Degradação de fármacos por peroxidação assistida por radiação ultravioleta e ozonização: atividade antimicrobiana e toxicidade
• Beneficiário: José Roberto Guimarães
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/09543-7 - Resíduos de medicamentos veterinários no ambiente
• Beneficiário: Susanne Rath
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/06201-0 - EMU concedido no processo 2013/09543-7- cromatógrafo líquido de ultraeficiência acoplado a detetores de arranjo de fotodiodos e espectrômetro de massas sequencial (UPLC-DAD-MS/MS)
• Beneficiário: Susanne Rath
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 13/07817-2 - Degradação de sulfonamidas e tetraciclinas por UV/H2O2 e O3: avaliação da atividade antimicrobiana e da toxicidade
• Beneficiário: Milena Guedes Maniero Ferreira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado