The drawbacks of using inorganic coagulants in water and wastewater treatment are the generation of large volumes of sludge, alkalinity requirements, and high concentrations of residual metals in the treated water. In accordance with the adoption of a circular economy in the wastewater sector, our systems are being reinvented to ensure water resources are enhanced and environmental impact is minimized.

This reclamation and reuse of wastewater techniques, combined with the regeneration of natural systems, is in line with sustainable development goals (SDG) aiming to increase water use efficiency while ensuring a sustainable supply of freshwater. Shifting to natural coagulants derived from plants and combined with proven adsorption processes will ensure excellent effluent quality as well as the ability to separate a wide range of pollutants. Activated carbon as an efficient adsorbent has shown good technical feasibility for the removal of many types of pollutants on an industrial scale. Faced with the challenges of creating a sustainable industry, particularly in water and wastewater treatment, there is a need to share current research and developments on advanced coagulation-adsorption processes, including advanced materials for coagulant-adsorption, treatments, and process optimization, as well as adsorbent disposal.

The objectives of this Special Issue are to contribute to the growth of the environment management industry in the field of water and wastewater treatment, as well as to share and understand the current knowledge on research into coagulation and adsorption processes and technology. We welcome high-quality research contributions describing conceptual, constructive, empirical, experimental, or theoretical work in the areas of advanced coagulants and adsorption material processes. Both original research and review articles are welcome.

Potential topics include but are not limited to the following:

• Sustainable materials for the production of coagulants/adsorbents, including natural and new materials, recovered materials, or combinations of these
• The performance or characterization of new sustainable materials for water and wastewater applications
• Coagulation/adsorption processes, including optimization processes, pre-treatment, post-treatment, and hybrid processes
• Sludge and adsorbent disposal
• Coagulants/adsorbents in industrial and domestic applications, including potential applications of materials and processes, and process control
• Performance verification and characterization for coagulants and adsorbents
• Phytotoxicity studies covering toxicity characteristics and assessment of treated water and produced sludge
• Economic feasibility and life cycle analysis, including environmental impacts and economic assessment of products or processes