Mobility of polivinylpyrrolidone coated silver nanoparticles in tropical soils.
Chemosphere
; 194: 543-552, 2018 Mar.
Article
em En
| MEDLINE
| ID: mdl-29241128
Experiments in saturated soil columns were performed to investigate the transport and retention of 25 nm and 75 nm silver nanoparticles stabilized with polyvinylpyrrolidone (PVP-AgNPs) in two Brazilian soils (sandy and sandy-clay). The normalized concentration of the PVP-AgNPs was obtained through a flow injection analysis method based on the surface plasmon ressonance effect of the metallic nanoparticles. The use of the ultraviolet-visible spectroscopy (UV-Vis) allows a rapid and low-cost analysis. The obtained breakthrough curves (BCs) were modeled with a deterministic model of solute transport in steady conditions of water flow and considering two regions of non-physical equilibrium; this model allowed the determination of the hydrodynamic parameters. It was found that the process occurs in condition of non-equilibrium, with a low mass transfer for larger NP, and that the process is predominantly advective and affected by the pore size of the soil packed in the columns. The BCs for PVP-AgNPs obtained by UV-Vis spectroscopy were compared with the BCs obtained by ICP-MS and with BCs of the bromide anion, confirming that the nanoparticles have a low retention and few modifications when transported through the soil column. These PVP-AgNPs are highly mobile and can be transported through the studied tropical soils, representing a potential environmental problem, due to the possibility of these materials reaching groundwater. On the contrary, the conservative behavior of PVP-AgNPs in the studied tropical soils, indicates its potential use as tracers, substituting the bromide anion which has been demonstrated to be not a good tracer in the same conditions.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prata
/
Solo
/
Povidona
/
Nanopartículas Metálicas
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
America do sul
/
Brasil
Idioma:
En
Revista:
Chemosphere
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido