Chitosan-grafted salicylaldehyde/algae composite for methyl violet dye removal: adsorption modeling and optimization

• Published in: International Journal of Phytoremediation
• Main Author: Agha H.M.; Abdulhameed A.S.; Wu R.; Jawad A.H.; ALOthman Z.A.; Algburi S.
• Format: Article
• Language: English
• Published: Taylor and Francis Ltd. 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85187138153&doi=10.1080%2f15226514.2024.2318777&partnerID=40&md5=8b497cea9528f7ef67cc111d4aa437c6

In this study, a hydrothermal approach was employed to graft chitosan (Chit)/algae (ALG) with salicylaldehyde (SA), resulting in the synthesis of a biocomposite named salicylaldehyde-based chitosan Schiff base/algae (Chit-SA/ALG). The main objective of this biocomposite was to effectively remove methyl violet (MV), an organic dye, from aqueous solutions. The adsorption performance of Chit-SA/ALG toward MV was investigated in detail, considering the effects of three factors: (A) Chit-SA/ALG dose (ranging from 0.02 to 0.1 g/100 mL), (B) pH (ranging from 4 to 10), and (C) time (ranging from 10 to 120 min). The Box–Behnken design (BBD) was utilized for experimental design and analysis. The experimental results exhibited a good fit with both the pseudo-second-order kinetic model and the Freundlich isotherm, suggesting their suitability for describing the MV adsorption process on Chit-SA/ALG. The maximum adsorption capacity of Chit-SA/ALG, as calculated by the Langmuir model, was found to be 115.6 mg/g. The remarkable adsorption of MV onto Chit-SA/ALG can be primarily attributed to the electrostatic forces between Chit-SA/ALG and MV as well as the involvement of various interactions such as n–π, π–π, and H-bond interactions. This research demonstrates that Chit-SA/ALG exhibits promising potential as a highly efficient adsorbent for the removal of organic dyes from water systems. © 2024 Taylor & Francis Group, LLC.