0
Article Tier 2 Nanoplastics Sign in to save

Charge mediated interaction of polystyrene nanoplastic (PSNP) with minerals in aqueous phase

Water Research 2020 177 citations

AI summary Read the abstract

Researchers investigated how polystyrene nanoplastics interact with common soil and sediment minerals, finding that positively charged iron oxide minerals (goethite and magnetite) strongly adsorb nanoplastics via electrostatic attraction and hydrogen bonding, while negatively charged clay minerals do not — providing mechanistic insight into how nanoplastics may accumulate in iron-rich soils and sediments.

Polymers

A large number of plastic products potentially become smaller particles, including nanoplastics, under multiple actions in the environment. The interactions between nanoplastic particles and constituents in the environment, such as minerals, would greatly affect the transport, fate and toxic effects of nanoplastics. In this study, the interactions of polystyrene nanoplastic (PSNP) with four typical minerals, including goethite, magnetite, kaolinite and montmorillonite, in aqueous phase were investigated. The stability of PSNP colloidal suspension decreased in the presence of the positively charged goethite or magnetite, while it was not affected by the negatively charged montmorillonite and kaolinite, suggesting that there was a strong electrostatic attraction between PSNP and the two iron oxides. Incubation of PSNP with other three metal oxides with different surface charges, MnO, AlO and SiO, confirmed the importance of electrostatic interaction in the stability of PSNP suspension. The transmission electron microscopy (TEM) analysis and batch adsorption experiments indicated that PSNP was effectively adsorbed on goethite or magnetite due to the strong electrostatic attraction between them. The Fourier transform infrared spectra (FTIR) and two-dimensional correlation spectroscopy (2D-COS) analyses indicated that there was strong hydrogen bonding between the -OH (γ-FeOOH) of goethite and PSNP, contributing to the higher adsorption of PSNP on goethite than magnetite. These findings shed light on the interactions of PSNP with mineral surfaces, and potential fate of PSNP under natural conditions in the water environment.

More Papers Like This

Article Tier 2

Impact of iron/aluminum (hydr)oxide and clay minerals on heteroaggregation and transport of nanoplastics in aquatic environment

AI summary Read the abstract

Researchers examined how polystyrene nanoplastics interact with nine different minerals in aquatic environments, finding that positively charged iron and aluminum (hydr)oxide minerals readily form aggregates with nanoplastics through electrostatic and hydrophobic forces, while humic acid and shifting pH significantly suppress this aggregation.

Article Tier 2

Polystyrene nanoplastics facilitate the Fe(II)-catalyzed ferrihydrite transformation into goethite and hematite under sedimentary conditions

AI summary Read the abstract

Researchers found that polystyrene nanoplastics significantly accelerate iron mineral transformation in sediments, speeding up the conversion of ferrihydrite into goethite and hematite by reducing surface charges on the mineral and enhancing electron transfer—an overlooked interaction that alters iron geochemistry and influences how nanoplastics behave in aquatic sediments.

Article Tier 2

Crystallinity- dependent heteroaggregation and co-sedimentation between polystyrene nanoplastics and iron (hydro)oxides

AI summary Read the abstract

Researchers found that the crystallinity of iron (hydro)oxide minerals strongly governs their tendency to aggregate with polystyrene nanoplastics in water — higher crystallinity produces more positive surface charges, stronger electrostatic attraction, and greater hydrogen bonding with nanoplastics, ultimately controlling how and where these combined particles settle in aquatic environments.

Article Tier 2

Deposition behaviors of carboxyl-modified polystyrene nanoplastics with goethite in aquatic environment: Effects of solution chemistry and organic macromolecules

AI summary Read the abstract

Researchers systematically measured how pH, ions, and dissolved organic molecules affect the settling of carboxylated nanoplastics onto the iron mineral goethite, finding that higher pH, multivalent anions, and organic macromolecules (especially alginate) strongly inhibit deposition through electrostatic repulsion and steric hindrance.

Article Tier 2

Transport of nanoplastics in porous media with ferrihydrite–humic acid coprecipitation: Effect of solution chemistry, nanoplastic size and aging degree

AI summary Read the abstract

Researchers investigated how ferrihydrite-humic acid coprecipitates in soil affect nanoplastic transport through sand columns, finding that the mineral-organic coating weakens iron oxide retention of polystyrene nanoplastics via steric hindrance and added negative charge, and that UV aging further enhances nanoplastic mobility by increasing surface hydrophilicity and electrostatic repulsion.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper