Silicon carbide ( SiC ) reinforced crosslinked chitosan polymer–adipic acid biocomposite for efficient anionic dye adsorption: characterization and adsorption enhancement

In this study, a silicon‐carbide‐reinforced crosslinked chitosan polymer–adipic acid biocomposite was synthesized and evaluated for its potential in removing eosin Y, a widely used industrial anionic dye, from aqueous solutions. The physicochemical properties of the chitosan–adipic acid/silicon carbide (CTS‐AA/SiC) composite—including surface porosity, crystallinity, morphology, functional groups, surface charge and elemental composition—were comprehensively characterized using Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller (BET) analysis, SEM, point of zero charge, XRD and energy‐dispersive X‐ray spectroscopy. The CTS‐AA/SiC composite exhibited a Langmuir surface area of 36.73 m 2 g –1 , a BET surface area of 24.85 m 2 g –1 , a total pore volume of 0.08638 cm 3 g –1 and an average pore diameter of 13.91 nm. Optimization of key operational parameters affecting dye removal was carried out using response surface methodology based on Box–Behnken design. Adsorption equilibrium data were best described by the Freundlich isotherm model, indicating multilayer adsorption onto a heterogeneous surface, with a maximum adsorption capacity of 172.25 mg g –1 . Kinetic analysis revealed that the adsorption process followed a pseudo‐second‐order model, suggesting chemisorption as the dominant mechanism. These results demonstrate that the CTS‐AA/SiC polymer composite is an efficient adsorbent with strong potential for application in industrial wastewater treatment.