Trends in recent advances of chitosan and alginate-based composite beads for wastewater remediation

Industrial wastewater pollution necessitates the urgent development of sustainable remediation technologies. While biopolymer-based adsorption offers a promising alternative, conventional adsorbents are costly and have regeneration limitations. This review systematically evaluates recent advances in composite beads formulated from chitosan and sodium alginate matrices, addressing current gaps in structure-property-performance (SPP) and techno-economic analyses. We highlight how integrating functional additives, specifically activated carbon (AC), graphene oxide (GO), and magnetite ( Fe 3 O 4 ), effectively mitigates pure biopolymer constraints. These specific hybrid architectures synergistically expand active surface areas (e.g., up to 22.6 m 2 /g in LDH-integrated systems), optimize thermodynamic binding, and facilitate rapid magnetic phase separation. Economically, leveraging biowaste precursors ensures highly competitive production costs with sustained efficiency over 5 to 10 regeneration cycles. Finally, we provide a strategic roadmap charting the evolution of these advanced composites into stimuli-responsive smart materials, extending their application beyond water purification into the broader circular bioeconomy, precision medicine, and smart agriculture.