Facile Synthesis of Cross-Linked Chitosan-Genipin/Algae Composite Adsorbent for Cationic Methyl Violet Dye Removal: Robust Modeling of Adsorption Using the Box-Behnken Design

• Published in: JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS
• Main Authors: Agha, Hasan M.; Abdulhameed, Ahmed Saud; Jawad, Ali H.; Khadiran, Tumirah; Alothman, Zeid A.; Wilson, Lee D.
• Format: Article; Early Access
• Language: English
• Published: SPRINGER 2024
• Subjects: Polymer Science
• Online Access: https://www-webofscience-com.uitm.idm.oclc.org/wos/woscc/full-record/WOS:001296998300001
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-024-03327-6

A biopolymer matrix of chitosan (CTS) and algae (AGA) was chemically modified with a natural genipin (GEN) cross-linker agent via hydrothermal process. The resulting green adsorbent (CTS-GEN/AGA) was evaluated for removal of the cationic dye (methyl violet, MV) from aqueous media. The optimization of MV adsorption onto CTS-GEN/AGA was performed using the Box-Behnken design (BBD), considering the variables of adsorbent dose (0.02-0.1 g/100 mL), pH (4-10), and time (20-300 min). The CTS-GEN/AGA demonstrated the highest MV removal (76.49%) for optimal operational parameters: CTS-GEN/AGA dosage (0.0938 g/100 mL), pH (8.4), and contact time (215.3 min). The adsorption isotherm analysis revealed a close fit between the experimental data of MV adsorption and the Temkin model. Furthermore, the adsorption kinetics are well-described by the pseudo-second-order model. The maximum adsorption capacity of CTS-GEN/AGA was 71.9 mg/g at 25 degrees C. The probable adsorption mechanism can be assigned to H-bonding, electrostatic forces, and n-pi stacking interactions. These findings highlight the potential of CTS-GEN/AGA as an effective adsorbent for treatment of wastewater for the removal of organic dyes.