Adsorption Mechanisms and Techniques for Aqueous Contaminant Removal

Adsorption has emerged as a versatile and cost-effective route for eliminating a wide spectrum of pollutants—from heavy metals and dyes to pharmaceuticals and radionuclides—from aqueous media. Fundamentally, adsorption involves the accumulation of solute species at the interface of a solid adsorbent and a liquid phase, governed by physisorption via van der Waals forces or chemisorption through the formation of chemical bonds. Key materials span traditional activated carbons and clays, novel biochars derived from agricultural residues, engineered metal–organic frameworks and two-dimensional nanosheets, as well as magnetic and polymer-based composites. Adsorption performance is characterised by isotherms, which describe equilibrium capacities, and kinetic models that reveal rate-limiting steps such as film diffusion or intra-particle transport. Recent advances have focused on tuning surface chemistry through functionalisation, enhancing porosity at the micro- and mesopore levels, and integrating intelligent features for in situ monitoring of contaminant uptake. Practical considerations include regeneration of spent adsorbents by thermal, chemical or supercritical methods, and life-cycle management to ensure sustainability. This integrated approach is driving forward scalable solutions for global water security and pollution mitigation.

Research from Nature Portfolio

Recent studies have demonstrated that controlled denaturation of collagen in fish scale waste can engender defect-rich structures that serve as highly effective adsorbents. Heating-induced defects not only introduce abundant binding sites but also impart fluorescence properties that enable simultaneous contaminant removal and optical tracking. In tests with rhodamine B dye, these upcycled biosorbents achieved over 90 percent removal within ten minutes, exemplifying how multifunctional natural materials can be transformed into sustainable, high-performance sorbents.

Adsorption Mechanisms and Techniques for Aqueous Contaminant Removal publication trend

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

Technical terms

Adsorption isotherm: A curve describing the equilibrium relationship between solute concentration in solution and the amount adsorbed per unit mass of adsorbent at constant temperature.

Biosorbent: A sorbent derived from biological materials (e.g. agricultural waste, algae or microbial biomass) used for the removal of pollutants from water.

Biochar: A carbon-rich material produced by pyrolysis of biomass, characterised by high surface area and porosity for contaminant uptake.

Functionalisation: Chemical modification of an adsorbent’s surface to introduce specific reactive groups or binding sites for target pollutants.

Regeneration: Processes (thermal, chemical or supercritical) applied to restore or enhance the adsorption capacity of spent adsorbents for repeated use.

References

1. Methods to prepare biosorbents and magnetic sorbents for water treatment: a review. Environmental Chemistry Letters (2023).
2. Electrospun polymeric nanohybrids with outstanding pollutants adsorption and electroactivity for water treatment and sensing devices. Advanced Composites and Hybrid Materials (2024).
3. Upcycling fish scales through heating for steganography and Rhodamine B adsorption application. Nature Communications (2023).
4. Modelling and Interpretation of Adsorption Isotherms. Journal of Chemistry (2017).