Nanoparticle Adsorption and Removal Techniques in Environmental Applications

Nanoparticle adsorption and removal strategies constitute a critical component of contemporary environmental remediation, addressing the persistent release of engineered and incidental nanoparticles into water bodies. A variety of adsorbent materials—ranging from activated carbons and metal–organic frameworks to polymeric cryogels and magnetic composites—have been engineered to capture metal and metal‐oxide nanoparticles through mechanisms such as electrostatic interaction, surface complexation and van der Waals forces. Key design parameters include specific surface area, pore size distribution and surface functionalisation, which together determine adsorption capacity, selectivity and regenerability. In parallel, separation techniques such as magnetic recovery and membrane filtration facilitate the practical deployment of nanoparticle‐laden adsorbents, allowing reuse or safe disposal. Mathematical modelling of equilibrium isotherms and kinetic uptake profiles underpins process optimisation, while coupling adsorption with catalytic degradation or antimicrobial activity broadens the scope of treatment technologies. Collectively, these advances underscore the global significance of nanoscale pollutant management for water security and ecosystem health.

Research from Nature Portfolio

Recent studies have demonstrated the exceptional performance of biomass‐derived activated carbons in removing silver nanoparticles from natural and treated waters. By deriving activated carbon from agricultural waste, researchers have achieved removal efficiencies exceeding 99 %, attributing the high affinity to electrostatic binding of Ag+ ions to oxygenated surface groups. A mixed first‐ and second‐order kinetic model was formulated to describe the adsorption dynamics across varying concentrations and ionic strengths.

Investigations into mussel-inspired magnetic nanocomposites have yielded core–shell microspheres comprising Fe₃O₄ and polydopamine. These composites combine strong magnetic responsiveness with abundant catechol functional groups to capture silver nanoparticles selectively. The adsorption follows a pseudo-second-order kinetic profile and fits a Langmuir isotherm, indicating monolayer coverage. Subsequent magnetic separation permits recovery of both the adsorbent and bound nanoparticles, which retain catalytic activity for pollutant reduction.

Nanoparticle Adsorption and Removal Techniques in Environmental Applications publication trend

The graph below shows the total number of articles in nanoparticle adsorption and removal techniques in environmental applications across all publications each year (not limited to Nature Index journals).

Technical terms

Adsorption isotherm: Relationship between the concentration of nanoparticles in solution and the amount adsorbed at equilibrium.

Pseudo-second-order kinetics: Model assuming the rate of adsorption is proportional to the square of the number of unoccupied sites.

Langmuir model: Isotherm describing monolayer adsorption on a homogeneous surface with a finite number of identical sites.

Metal–organic framework (MOF): Porous crystalline material composed of metal ions coordinated to organic ligands, offering high surface area and tunable pores.

Cryogel: Macroporous polymeric network formed under cryogenic conditions, used as an adsorbent support for rapid fluid transport and nanoparticle capture.

References

1. Removal of silver nanoparticles by mussel-inspired Fe3O4@ polydopamine core-shell microspheres and its use as efficient catalyst for methylene blue reduction. Scientific Reports (2017).
2. Chitosan Glutaraldegyde Cryogels for Wastewater Treatment and Extraction of Silver Nanoparticles. Processes (2023).
3. Adsorption of Silver Nanoparticles from Aqueous Solution by Multiwalled Carbon Nanotubes. Advances in Nanoparticles (2017).