We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Investigating transport kinetics of polystyrene nanoplastics in saturated porous media
Summary
Researchers investigated how ionic strength, pH, and organic matter influence the transport of polystyrene nanoplastics through saturated porous media using column experiments and DLVO modeling, finding that increasing sodium ion concentrations promote nanoplastic aggregation and reduce mobility in soil and groundwater systems.
Understanding the fate and transport of polystyrene nanoparticles (PSNPs) in porous media under various conditions is necessary for evaluating and predicting environmental risks caused by microplastics. The transport kinetics of PSNPs are investigated by column experiment and numerical model. The surface of DLVO interaction energy is calculated to analyze and predict the adsorption and aggregation of PSNPs in porous media, which the critical ionic strength of PSNPs can be accurately investigated. The results of the DLVO energy surface suggest that when the concentration of Na+ increases from 1 mM to 50 mM, the DLVO energy barrier of PSNPs-silica sand (SS) decreases from 78.37 kT to 5.46 kT. As a result, PSNPs are easily adsorbed on the surface of SS and the mobility of PSNPs is reduced under the condition of a high concentration of Na+ (PSNPs recovery rate decreases from 62.16% to 3.65%). When the concentration of Ca2+ increases from 0.1 mM to 5 mM, the DLVO energy barrier of PSNPs-SS decreases from 12.10 kT to 1.90 kT, and PSNPs recovery rate decreases from 82.46% to 4.27%. Experimental and model results showed that PSNPs mobility is enhanced by increasing initial concentration, flow velocity and grain size of SS, while the mobility of PSNPs with larger particle diameter is lower. Regression analysis suggests that kinetic parameters related to PSNPs mobility are correlated with DLVO energy barriers. The environmental behavior and mechanism of PSNPs transport in porous media are further investigated in this study, which provides a scientific basis for the systematic and comprehensive evaluation of the environmental risk and ecological safety of nano-plastic particles in the groundwater system.
Sign in to start a discussion.
More Papers Like This
Co-transport of polystyrene nanoplastics and soil colloids in saturated porous media: influence of pH and ionic strength
Researchers examined the co-transport of polystyrene nanoplastics and soil colloids in saturated porous media, finding that solution pH and ionic strength significantly influenced their combined transport behavior through mechanisms explained by DLVO theory and adsorption tests.
Transport of polystyrene nanoplastics in natural soils: Effect of soil properties, ionic strength and cation type
Researchers used column experiments across three soil types to show that polystyrene nanoplastic transport is governed by soil iron and aluminum oxide content and pH — with high-pH, low-oxide soils allowing up to 97% nanoplastic passage — and that calcium ions and higher ionic strength significantly increase retention, revealing that soil chemistry strongly controls nanoplastic mobility toward groundwater.
Influence of natural organic matters on fate of polystyrene nanoplastics in porous media
Researchers investigated how natural organic matter (NOM) affects the transport of polystyrene nanoplastics through porous media, finding that NOM facilitates nanoplastic movement by increasing energy barriers, while metal ions reduce transport by promoting nanoplastic aggregation.
Vertical transport of polystyrene nanoplastics in natural soils under unsaturated conditions: influence of particle size and texture
Laboratory experiments showed that polystyrene nanoplastics can travel downward through unsaturated soils, but larger particles and clay-rich soils retain them more effectively than smaller particles in sandy soils. Understanding how nanoplastics move through soil is important for predicting whether they will reach groundwater and contaminate drinking water sources.
Effect of low-molecular-weight organic acids on the transport of polystyrene nanoplastics in saturated porous media
Researchers studied how low-molecular-weight organic acids (common in soil and groundwater) affect the movement of polystyrene nanoplastics through saturated porous media, finding that low concentrations promote transport while high concentrations increase particle deposition, with the effect scaling with the number of functional groups on the organic acid.