We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Impact of diatomit on the transport behavior of unmodified and carboxyl-modified nanoplastics in saturated porous media
Summary
This study examined how diatomite affects the transport of carboxyl-modified microplastics through porous media, finding that diatomite addition alters the surface interactions governing plastic mobility in soil and aquifer environments.
Due to the extensive use of plastic products and unreasonable disposal, nanoplastics contamination has become one of the important environmental problems that mankind must face. The composition and structure of porous media can determine the complexity and diversity of the transport behavior of nanoplastics. In this study, the influence of diatomite (DIA) on the nanoplastics transport in porous media is investigated by column experiments combined with XDLVO interaction energy and transport model. Results suggest that the recovery rates of unmodified polystyrene nanoparticles (PSNPs) and carboxyl-modified polystyrene nanoparticles (PSNPs-COOH) in the porous media containing DIA decreases compared with that in the pure quartz sand (QS), and the BTCs showed a "blocking" pattern. The presence of DIA inhibits the transport of both PSNPs and PSNPs-COOH, but the inhibition is not significant. This may be because the presence of DIA provides more favorable deposition sites for PSNPs and PSNPs-COOH to some extent. However, since DIA itself carries a certain negative charge, this can only play a role in compressing the double electric layer for PSNPs and PSNPs-COOH with the same negative charge, and cannot destabilize them. The migration capacity of PSNPs and PSNPs-COOH is strongest in the DIA-QS porous media at pH = 7, and is weak at pH = 9 and pH = 5. The inhibition of migration at pH = 9 can be attributed to the dissolution of the DIA surface under alkaline conditions and the formation of pore and defect structures, which provide more deposition sites for PSNPs and PSNPs-COOH. The presence of humic acid (HA) leads to an increase in the mobility of PSNPs and PSNPs-COOH, and the mobility is enhanced with HA concentration. The mobility of PSNPs and PSNPs-COOH in DIA-QS decreases with ionic valence and ionic strength, and PSNPs-COOH is more significantly inhibited compared to PSNPs.
Sign in to start a discussion.
More Papers Like This
Transport of different microplastics in porous media: Effect of the adhesion of surfactants on microplastics
Researchers investigated how surfactant adhesion on different microplastic surfaces affects their transport through porous media, finding that surfactant interactions vary with microplastic type and significantly alter their mobility in subsurface environments.
Effect of biosurfactants on the transport of polyethylene microplastics in saturated porous media
This study examined how biosurfactants -- surface-active compounds produced by microorganisms -- affect the transport of polyethylene microplastics through saturated porous media. Biosurfactants altered microplastic surface charge and mobility, generally enhancing transport through soil-like media, with implications for assessing the risk of microplastic groundwater contamination following soil remediation treatments.
Behaviour and transport of microplastics under saturated flow conditions in sediments and soils
Researchers investigated the behavior and transport of microplastics under saturated flow conditions in sediments and soils, examining how physical and chemical properties of microplastic particles influence their mobility through porous geological media. The study addressed knowledge gaps in understanding subsurface microplastic transport relevant to groundwater contamination and the fate of microplastics deposited in terrestrial environments.
Transport and deposition of microplastic particles in saturated porous media: Co-effects of clay particles and natural organic matter
Researchers performed column experiments to study how clay particles and natural organic matter affect microplastic transport through saturated porous media, finding that both colloids reduced MP mobility through heteroaggregation and that their combined presence produced the greatest reduction in transport.
Nanoplastics as carriers of organic pollutants in seawater-saturated porous media: a quantitative comparison of transport pathways
Researchers quantitatively compared transport pathways of non-polar organic pollutants carried by nanoplastics through seawater-saturated porous media, demonstrating that the carrier effect of nanoplastics is the primary mechanism inhibiting pollutant migration and enabling their co-transport in coastal and marine subsurface environments.