A green approach to DDT degradation and metabolite monitoring in water comparing the hydrodechlorination efficiency of Pd, Au-on-Pd and Cu-on-Pd nanoparticle catalysis

Leila Dorácio Mendes; Gabrieli Bernardi; Welman Curi Elias; Daniela C de Oliveira; Josiel Barbosa Domingos; Eduardo Carasek

doi:10.1016/j.scitotenv.2020.143403

A green approach to DDT degradation and metabolite monitoring in water comparing the hydrodechlorination efficiency of Pd, Au-on-Pd and Cu-on-Pd nanoparticle catalysis

Sci Total Environ. 2021 Mar 15:760:143403. doi: 10.1016/j.scitotenv.2020.143403. Epub 2020 Nov 6.

Authors

Leila Dorácio Mendes¹, Gabrieli Bernardi¹, Welman Curi Elias¹, Daniela C de Oliveira², Josiel Barbosa Domingos¹, Eduardo Carasek³

Affiliations

¹ Universidade Federal de Santa Catarina, Departamento de Química, Florianópolis, Santa Catarina 88040-900, Brazil.
² Laboratório Nacional de Luz Síncrotron, C.P. 6192, Campinas, São Paulo 13083-970, Brazil.
³ Universidade Federal de Santa Catarina, Departamento de Química, Florianópolis, Santa Catarina 88040-900, Brazil. Electronic address: eduardo.carasek@ufsc.br.

PMID: 33190896
DOI: 10.1016/j.scitotenv.2020.143403

Abstract

DDT (1,1,1-trichloro-2,2-bi(p-chlorophenyl)-ethane) and its metabolites (DDD, 1,1-dichloro-2,2-bis-(4'-chlorophenyl)ethane, and DDE, 1,1-dichloro-2,2-bis-(4'-chlorophenyl)ethylene) are persistent organic pollutants that can be catalytically degraded into a less toxic and less persistent compound. In this work, ecofriendly methodologies for catalyst synthesis, catalytic degradation of DDT and reaction monitoring have been proposed. Three types of Pd-based nanoparticles, NPs, (Pd, Au-on-Pd and Cu-on-Pd) were synthesized and used for catalytic hydrodechlorination of DDT and its metabolites. The structural and electronic properties of NPs were investigated using TEM and XAS spectroscopy. Au-on-Pd showed the highest hydrodechlorination efficiency within 1 h of reaction. To obtain the best reaction conditions, the effects of H₂ flow and base addition Au-on-Pd NPs activity were investigated. To study the effectiveness of the different NPs, a solvent-free analytical method was optimized to detect and measure DDT and its by-products. The SPME-GC-MS method provided low detection limits (0.03 μg L^-1) and high recovery (≥88.75%) and was a valuable tool for the NP degradation study. In this way, a green method for degradation and monitoring of DDT and its by-products in water was achieved.

Keywords: Catalytic hydrodechlorination (HDC); DDT; Metabolites; Nanoparticles; Water.