Preparation of new MOF-808/chitosan composite for Cr(VI) adsorption from aqueous solution: Experimental and DFT study. (15th July 2022)

• Record Type: Journal Article
• Authors: Valadi, Farshad Mirzaee; Shahsavari, Shayan; Akbarzadeh, Elham; Gholami, Mohammad Reza
• Is Part Of: Carbohydrate polymers. Volume 288(2022)
• Publication Date: 2022-07-15
• Subjects: Adsorption -- MOF-808 -- Chitosan -- Cr(VI) -- DFT; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2022.119383
• Languages: English
• ISSNs: 0144-8617

Abstract

Abstract: In this study, a series of Zirconium-based MOF and chitosan composites (MOF-808/chitosan) were synthesized as efficient adsorbent for Cr(VI) ions elimination from aqueous solution. MOF-808/chitosan structure and morphology was characterized by FE-SEM, EDX, XRD, BET, zeta potential analysis, FT-IR, XPS techniques. The kinetic studies ascertained that Cr(VI) adsorption over MOF-808/chitosan followed pseudo-second-order kinetic model. The adsorption isotherms fitted the Langmuir isotherm model, implying on homogeneously adsorption of Cr(VI) on the surface of MOF-808/chitosan. According to the Langmuir model, the maximum capacity was obtained to be 320.0 mg/g at pH 5. Thermodynamic investigation proposed spontaneous (ΔG° < 0), disordered (ΔS° > 0) and endothermic (ΔH° > 0) for adsorption process. Besides, MOF-808/chitosan displayed an appropriate reusability for the elimination of Cr(VI) ions from their aqueous solutions for six successive cycles. DFT study of the adsorption process displayed and confirmed the role of hydrogen bonding and electrostatic attraction simultaneously. Graphical abstract: Unlabelled Image Highlights: A series of Zirconium-based MOF and chitosan composites was synthesized. MOF-808/chitosan indicated promising potential for Cr(VI) adsorption. The maximum capacity was obtained to be 320.0 mg g −1 at pH = 5. DFT was applied to study the possible interaction between adsorbent and Cr(VI).