We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Surface change of microplastics in aquatic environment and the removal by froth flotation assisted with cationic and anionic surfactants
AI summary Read the abstract
This study found that microplastics become less water-repellent after months of sitting in natural river water due to surface weathering and mineral buildup, which makes them harder to remove by flotation methods. The researchers then showed that adding surfactants (soap-like chemicals) could restore the microplastics' water-repellent properties and make flotation effective again. This work advances practical methods for cleaning microplastics out of contaminated water.
Microplastics (MPs) are increasingly released into the environment due to the widespread usage and improper management of plastics. Considerable research efforts have been devoted to the remediation of MPs. Froth flotation has been demonstrated as an effective method to remove MPs in water and sediment. However, there is a lack of knowledge on the regulation of the hydrophobicity/hydrophilicity of MPs surfaces. We found that exposure to the natural environment resulted in the increased hydrophilicity of MPs. The flotation efficiencies of polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), and polyethylene glycol terephthalate (PET) MPs decreased to zero after six months of natural incubation in rivers. According to various characterizations, the hydrophilization mechanism is mainly correlated with surface oxidation and the deposition of clay minerals. Inspired by surface wettability conversion, we applied surfactants (collectors) to enhance MPs hydrophobicity and flotation efficiency. Anionic sodium oleate (NaOL) and cationic dodecyl trimethyl ammonium chloride (DTAC) were used to regulate surface hydrophobicity. The effects of collector concentration, pH, conditioning time, and metal ions on MPs flotation were thoroughly elucidated. Characterizations and adsorption experiments were performed to describe the heterogeneous adsorption of surfactants on MPs surfaces. The interaction between surfactants and MPs was explained through density functional theory (DFT) simulations. The dispersion energy between hydrophobic hydrocarbon chains attracts collectors on the MPs surface, and the collector molecules wrap and laminate to MPs surfaces. Flotation using NaOL exhibited a higher removal efficiency, and NaOL was environmentally friendly. Subsequently, we investigated the activation of Ca, Fe, and Al to further improve the collecting efficiency of NaOL. Under the optimized conditions, MPs in natural rivers could be removed by froth flotation. This study shows the great promise of froth flotation for the application of MPs removal.
More Papers Like This
Effects and applications of surfactants on the release, removal, fate, and transport of microplastics in aquatic ecosystem: a review
AI summary Read the abstract
Researchers reviewed how surfactants interact with microplastics in aquatic environments, finding that surfactants can modify microplastic surface properties and influence their removal during wastewater treatment processes like filtration, flotation, and coagulation. The study suggests that surfactant concentration is a crucial factor affecting both the transport and the pollutant-carrying capacity of microplastics in water systems.
Is froth flotation a potential scheme for microplastics removal? Analysis on flotation kinetics and surface characteristics
AI summary Read the abstract
This study evaluated froth flotation as a method for removing microplastics from water, finding that surface hydrophobicity governs flotation efficiency and that the technique shows promise as a scalable treatment option for certain polymer types.
The effects of ultraviolet irradiation treatment on the surface properties of microplastics
AI summary Read the abstract
UV irradiation was used to modify microplastic surface properties, making them more hydrophilic, which improved flotation efficiency — a water treatment technique that relies on particle hydrophobicity — demonstrating a pretreatment approach to enhance MP removal from water.
A review of microplastic surface interactions in water and potential capturing methods
AI summary Read the abstract
This review examines how microplastics behave as colloidal particles in water, generating surface charges that drive interactions with other contaminants and environmental constituents. The study explains that classical colloidal theory can help predict microplastic behavior, and that surface modifications from environmental exposure influence how these particles interact in water systems. Several removal techniques including coagulation, filtration, and air flotation are discussed as potential methods for capturing microplastics in water treatment.
Microplastics in river water: occurrence, weathering, and adsorption behaviour
AI summary Read the abstract
Researchers examined microplastics in river water, characterizing their occurrence, degree of weathering, and capacity to adsorb co-contaminants. The study highlights microplastics as vectors that can transport and re-release other pollutants in freshwater systems.
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.