Green synthesis of chitosan-ZIF67 composite beads for efficient removal of Malachite Green and Tetracycline

• Published in: Chemical engineering science 2025-02, Vol.304, p.121017, Article 121017
• Main Authors: Shahmansoori, Maryam, Yaghmaei, Soheila, Mahmoodi, Niyaz Mohammad
• Format: Article
• Language: English
• Subjects: Chitosan-ZIF-67 biocomposite; Efficient and easily separable; Hierarchically green synthesis; Pollutant adsorption; Room temperature
• ISSN: 0009-2509
• DOI: 10.1016/j.ces.2024.121017

•Novel chitosan and ZIF-67 biocomposites were green synthesized for dye and tetracycline removal.•Dye removal and adsorption capacity of biocomposite are 96 %and 476 mg/g.•The π-π stacking and electrostatic interactions are the dominant dye adsorption mechanisms.•Dye removal followed the Freundlich isotherm and pseudo-second-order kinetic model. To address the challenges posed by conventional water treatment technologies, it is essential to develop non-toxic adsorbents that are highly effective in removing pollutants. Herein, innovative, environmentally friendly chitosan-zeolitic imidazolate framework 67 (CSZ67) biocomposite beads were synthesized. They were used to remove the MG dye and Tetracycline. The Co2+ ions within the chitosan/Co2+ matrix serve as nucleation sites for the in-situ growth of ZIF-67. CSZ67 biocomposite beads with different [CS]:[Co] molar ratios named CSZ67-1 (1:0.5), CSZ67-2 (1:0.34), and CSZ67-3 (1:0.17) were synthesized. CSZ67-1 biocomposite exhibited the highest removal efficiency (96 %), and adsorption capacity (476 mg/g). The electrostatic interactions and π-π stacking are the dominant adsorption mechanisms. Dye removal follows the pseudo-second-order kinetic and Freundlich isotherm. The findings indicated that the biocomposite CSZ67-1, demonstrating a 75 % removal efficiency for tetracycline, not only exhibits high efficacy in adsorbing malachite green cationic dye but also performs effectively in the adsorption of tetracycline.