Preparation and Application of Tussah Sericin-Modified Chitosan Adsorbent

Abstract

This study presents a novel tussah sericin-modified chitosan composite (S-CS) with exceptional efficiency for carmine dye removal synthesized via glutaraldehyde crosslinking. The sericin used for the preparation of the adsorbent was recycled from tussah cocoon wastewater, implying its alignment with the “waste-to-wealth” principle. Further, the structural characterization of this adsorbent via SEM, FTIR, and BET analyses confirmed the formation of a porous architecture following modification with sericin, and this porous architecture enhanced adsorption efficacy as evidenced by the high BET surface area (13.3142 m² g⁻¹) and average pore size (22.78 nm) obtained for the material. Under optimal conditions (0.1000 g S-CS, 30 °C, and 150 rpm), the adsorbent showed a carmine adsorption capacity of 98.5 mg g⁻¹ and its carmine removal efficacy reached 98.37% within 40 min. Via FTIR spectroscopy, we identified hydrogen bonding interactions between S-CS and carmine dye as the key adsorption mechanism. Additionally, the adsorbent retained >90% efficiency after five regeneration cycles, highlighting its reusability. These findings not only advance the valorization of sericin waste but also provide a cost-effective option for textile effluent treatment. In future, it would be necessary to investigate the scalability and industrial integration of this adsorbent to support circular economy initiatives.