Preparation of novel clay/chitosan/ZnO bio-composite as an efficient adsorbent for tannery wastewater treatment

Niloy Chandra Das; Mohammed Mizanur Rahman; Sumaya F Kabir

doi:10.1016/j.ijbiomac.2023.126136

Preparation of novel clay/chitosan/ZnO bio-composite as an efficient adsorbent for tannery wastewater treatment

Int J Biol Macromol. 2023 Sep 30:249:126136. doi: 10.1016/j.ijbiomac.2023.126136. Epub 2023 Aug 4.

Authors

Niloy Chandra Das¹, Mohammed Mizanur Rahman², Sumaya F Kabir³

Affiliations

¹ Department of Footwear Engineering, Institute of Leather Engineering and Technology, University of Dhaka, Dhaka 1209, Bangladesh.
² Department of Footwear Engineering, Institute of Leather Engineering and Technology, University of Dhaka, Dhaka 1209, Bangladesh; Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering and Technology, University of Dhaka, Dhaka 1000, Bangladesh.
³ Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering and Technology, University of Dhaka, Dhaka 1000, Bangladesh. Electronic address: sumaya.kabir@du.ac.bd.

PMID: 37543262
DOI: 10.1016/j.ijbiomac.2023.126136

Abstract

This study focuses on the preparation of an activated clay/chitosan/ZnO bio-composite using solvent casting method. Clay was activated through microwave radiation using 1 M H₂SO₄ at a minimum liquid to solid ratio (L/S). Chitosan was extracted from waste prawn shell and ZnO nanoparticles (ZnO-NPs) were synthesized from zinc acetate di-hydrate (Zn (CH₃CO₂)₂·2H₂O) using the sol-gel method. The produced bio-composite were characterized using FT-IR, TGA, XRD and SEM. Response surface methodology (RSM) was used for experimental design to find out the optimum conditions, e.g., pH of the solution, dosage of adsorbent and contact time for the removal of methylene blue (MB) and Cr (VI) using MINITAB 18.1 software. The optimum conditions obtained for the highest removal of MB were pH 9.57, dosage 55.44 mg and contact time 114.09 min. Similarly, for the highest removal of Cr (VI) the optimum conditions were pH 3.75, dosage 67.42 mg and contact time 111.27 min. Applying these optimum conditions, the highest removal efficiency for MB and Cr (VI) was obtained at 84.21 % and 82.67 % with 9.57 mg g^-1 and 10.45 mg g^-1 of adsorption capacity respectively. The adsorption data were studied for both Langmuir and Freundlich isotherm. The value of maximum Langmuir sorption was (q_m) 17.346 mg g^-1 and 17.621 mg g^-1 for MB and Cr (VI) respectively.

Keywords: Bio-composite; Chitosan; MB; RSM; ZnO.

MeSH terms

Adsorption
Chitosan* / chemistry
Clay
Hydrogen-Ion Concentration
Kinetics
Methylene Blue / chemistry
Spectroscopy, Fourier Transform Infrared
Water Pollutants, Chemical* / chemistry
Water Purification* / methods
Zinc Oxide* / chemistry

Substances

Chitosan
Clay
Zinc Oxide
Water Pollutants, Chemical
Methylene Blue