Anoxic degradation of chlorpyrifos by zerovalent monometallic and bimetallic particles in solution

Autor(es)

Graca, Catia A. L. ^[1] ; Mendes, Maria Anita ^[2] ; Teixeira, Antonio Carlos S. C. ^[2] ; de Velosa, Adriana Correia ^[3]

Afiliação do(s) autor(es)

^[1] Univ Porto, Fac Engn, Lab Separat & React Engn, Lab Catalysis & Mat LSRE LCM, Rua Dr Roberto Frias, P-4200465 Porto - Portugal

^[2] Univ Sao Paulo, Dept Chem Engn, Escola Politecn, Av Prof Luciano Gualberto, Tr 3, BR-05508010 Sao Paulo - Brazil

^[3] Carnegie Mellon Univ, Dept Civil & Environm Engn, Pittsburgh, PA 15213 - USA

• Tipo de documento: Artigo Científico
• Fonte: Chemosphere; v. 244, APR 2020.
• Citações Web of Science: 0

Resumo

The degradation of highly toxic and persistent chlorinated organic compounds by zerovalent metals (ZVMs) has received considerable attention for in situ groundwater remediation. Due to its abundance and low toxicity, iron has been mostly applied for such purposes, despite several limitations, such as rapid surface passivation and little efficacy towards certain contaminants. Given that, we evaluated monometallic zerovalent iron (ZVI), copper (ZVC) and zinc (ZVZ), and bimetallic copper-coated ZVI (ZVI/Cu) and ZVZ (ZVZ/Cu) for anoxic reductive degradation of chlorpyrifos (CP). Two approaches to enhance metal reactivity were investigated: the synthesis of bimetallic particles with copper and the comparison between micro and nanoparticles. All of the tested monometallic and bimetallic particles dechlorinated the target molecule, although complete chlorine removal was not achieved by any metal during the 30d treatment period. Coating the zerovalent monometallic particles with copper enhanced reactivity. Reactivity was ZVC > ZVZ > ZVI for monometallic particles and ZVZ/Cu > ZVI/Cu for bimetallic microparticles. The analysis of the degradation products indicated the presence of dechlorinated compounds as well as 3,5,6-trichloro-2-pyridinol, a hydrolysis product. (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 13/50218-2 - CEPEMA - Centro Cooperativo em Engenharia Ambiental
• Beneficiário: Claudio Augusto Oller do Nascimento
• Modalidade de apoio: Auxílio à Pesquisa - Temático