We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Coupled Influence of Magnetic Biochar and Solution Chemistries on Retention and Release of Nanoplastics in Porous Media
Summary
This study examined how magnetic biochar — a carbon-based material used in soil and groundwater remediation — affects the movement and retention of nanoplastics in porous soil-like media under varying water chemistry conditions. Magnetic biochar significantly increased nanoplastic retention and reduced their mobility through the porous medium, and the effect depended on the nanoplastics' surface chemistry, ionic strength, and the presence of organic matter. The findings suggest that adding biochar to contaminated soils could be a practical strategy to reduce the spread of nanoplastics through groundwater systems.
Magnetic biochar (MBC), as an environmentally friendly material, has been extensively used for the remediation of soil and groundwater contamination. The retention and release of nanoplastics (NPs) with carboxyl (NPs-COOH) or amino functionalization (NPs- NH2) in saturated porous media were investigated under varying conditions of ionic strength (IS), MBC addition, humic acid (HA) concentration, and cation types. The reversible and irreversible retention of NPs was examined by altering the IS, increasing the solution pH, and inducing cation exchange. The results revealed that MBC enhanced the surface roughness of the media, thereby inhibiting NPs' transport. The HA promoted NPs-NH2 transport more effectively than NPs-COOH due to electrostatic repulsion, steric hindrance, and competition for deposition sites. Under a reduced IS and increased pH, a portion of the retained NPs was released, with NPs-NH2 showing a greater release than NPs-COOH, indicating reversible retention. Additionally, the stronger charge-shielding and cation-bridging effects of Ca2+ significantly enhanced the retention of NPs. Cation exchange resulted in less NPs being released, as most were irreversibly retained in deeper primary minima. However, a small number of retained NPs were remobilized by electrical double layer expansion, surface deprotonation, and cation exchange, indicating reversible retention. These findings provide valuable insights into the fate of NPs in the environment.
Sign in to start a discussion.
More Papers Like This
Transport characteristics of polystyrene microplastics in saturated porous media with biochar/Fe3O4-biochar under various chemical conditions
Biochar and iron oxide-modified biochar (Fe3O4-biochar) reduced the transport of polystyrene microplastics through sandy porous media by increasing surface attachment, with the effect modulated by humic acid concentration and ionic conditions. The findings suggest that biochar soil amendments could help immobilize MPs in contaminated agricultural soils and reduce their leaching to groundwater.
Polyvinyl chloride nanoplastics transport inhibited in natural sandy soil by iron-modified biochar
Researchers tested iron-modified biochar amendments in sandy soil columns and found that both magnetic corncob and walnut shell biochars significantly slowed the transport of polyvinyl chloride nanoplastics, reducing breakthrough from 85% toward near-complete retention, with the effect strengthened by higher ionic strength and divalent cations like calcium.
The individual transport, cotransport and immobilization with solar pyrolysis biochar of microplastics and plasticizer in sandy soil
Researchers tracked the individual transport, co-transport, and immobilization of microplastics in porous media, finding that plastic particle behavior differs significantly depending on surface charge and pore structure interactions. The results improve predictions of where microplastics migrate and accumulate in soils and aquifers.
Recent advances and factors affecting the adsorption of nano/microplastics by magnetic biochar
This review examines recent advances in using magnetic biochar to adsorb nano- and microplastics from aquatic environments. Researchers found that magnetic biochar offers advantages over traditional biochar by enabling easy separation from water using magnets, avoiding secondary pollution from filtration. The study identifies key factors affecting adsorption efficiency and highlights magnetic biochar as a promising tool for microplastic remediation in contaminated water.
Adsorptive behavior of micro(nano)plastics through biochar: Co-existence, consequences, and challenges in contaminated ecosystems
This review examines how biochar can adsorb micro- and nanoplastics with over 90% removal efficiency in aqueous systems, while also discussing their combined effects on soil properties, microbial communities, and plant growth.