The Effects of Solar Irradiation on Copper Speciation and Organic Complexation

Autor(es)

Tonietto, Alessandra E. ^[1] ; Lombardi, Ana Teresa ^{[2, 1]} ; Vieira, Armando A. H. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, PPGQ, Dept Quim, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Bot, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 22, n. 9, p. 1695-1700, SEP 2011.
• Citações Web of Science: 6

Resumo

The aims of this research were to evaluate the effects of solar irradiation on copper speciation in water samples obtained in eutrophic and metal contaminated reservoir. Anodic stripping voltammetry and ion selective electrode were used for metal determinations of solar irradiated and non-irradiated samples. The results showed that after 7 h of solar irradiation, dissolved organic matter (DOM) was degraded promoting the increase of labile, free Cu(2+) ions and dissolved inorganic carbon (DIC). Decreases of ligand concentration (C(L)) and dissolved organic carbon (DOC) were also observed. Conditional stability constant (logK') values varied for two sampling sites, but remained unchanged for the others. The present results demonstrated that photochemical reactions affected copper speciation and Cu-DOM interactions. This research is a contribution to the understanding of biogeochemical cycle of copper and highlights some ecological implications of photooxidation in freshwater ecosystems, such as the increase of copper bioavailability. (AU)

• Processo FAPESP: 08/03487-0 - Cultivo de microalgas em fotobiorreator como ferramenta para o sequestro do CO2 atmosférico
• Beneficiário: Ana Teresa Lombardi
• Linha de fomento: Auxílio à Pesquisa - Programa BIOEN - PITE
• Processo FAPESP: 05/51263-5 - Destino da matéria orgânica dissolvida liberada por Cyanobacteria em um reservatório eutrofizado do Rio Tietê: estudo de processos
• Beneficiário: Armando Augusto Henriques Vieira
• Linha de fomento: Auxílio à Pesquisa - Temático