Chitosan-Schiff base nano silica hybrid system for azo acid dye removal: Multivariable optimization, desirability function, and adsorption mechanism

• Published in: Inorganic Chemistry Communications
• Main Author: Wu R.; Saud Abdulhameed A.; ALOthman Z.A.; Yong S.K.; Wilson L.D.; Jawad A.H.; Algburi S.
• Format: Article
• Language: English
• Published: Elsevier B.V. 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85187997300&doi=10.1016%2fj.inoche.2024.112237&partnerID=40&md5=dc7886329090862656f271345ecb4869

The facile synthesis of cross-linked chitosan-glutaraldehyde/nano silica (CHS-GLA/n-Silica) nanocomposite was accomplished in two steps including the functionalization of a natural biopolymer (CHS) with an inorganic nanomaterial (n-Silica), followed by a cross-linking process with glutaraldehyde (GLA). The ability of CHS-GLA/n-Silica to remove acid red 88 (AR88) dye from an aqueous system was optimized by the Box–Behnken design (BBD), taking into consideration the factors affecting adsorption (CHS-GLA/n-Silica dose (0.02–0.1 g/100 mL); time (10–60 min); and pH (4–10). The equilibrium behavior of AR88 by CHS-GLA/n-Silica is clearly illustrated by the Langmuir and Temkin isotherms. The kinetics of AR88 adsorption by CHS-GLA/n-Silica were appropriately described by a pseudo-second-order model. CHS-GLA/n-Silica displays an adsorption capacity of 115.9 mg/g. The electrostatic forces between the positively charged CHS-GLA/n-Silica and the AR88 anions, as along with n-π, and H-bond interactions, which accounts for the efficient adsorption of AR88 onto the CHS-GLA/n-Silica. This study demonstrates that CHS-GLA/n-Silica has promising potential as an adsorbent for the effective removal of synthetic dyes from wastewater. © 2024 Elsevier B.V.