Mesoporous biohybrid epichlorohydrin crosslinked chitosan/carbon-clay adsorbent for effective cationic and anionic dyes adsorption.

Epichlorohydrin crosslinked chitosan/carbon-clay (CSCC) biohybrid adsorbent was prepared for the adsorption of cationic methylene blue (MB) and anionic azo acid blue 29 (AB 29). The 40:60 wt% of chitosan (CS) and carbon-clay (CC) was selected as the best biohybrid adsorbent (CS40CC60) for the adsorption of both dyes. The adsorption of MB and AB 29 on CS40CC60 was carried out in a batch process to investigate the effects of initial dye concentration (25-400 mg/L), initial pH (3-11), contact time and adsorption temperature (30, 40 and 50 °C). The kinetics results of dyes adsorption onto CS40CC60 fit well to the pseudo-second-order model. The isotherms analysis demonstrated that the Freundlich isotherm described the adsorption data, and the qmax (mg/g) were 95.31 for MB and 167.35 for AB29 at 50 °C. These findings reveal the potential and effectiveness of the newly prepared biohybrid adsorbent for the adsorption of both dyes.