3D kaolinite/g-C3N4-alginate beads as an affordable and sustainable photocatalyst for wastewater remediation

Akash Balakrishnan; Mahendra Chinthala; Rajesh Kumar Polagani

doi:10.1016/j.carbpol.2023.121420

3D kaolinite/g-C₃N₄-alginate beads as an affordable and sustainable photocatalyst for wastewater remediation

Carbohydr Polym. 2024 Jan 1:323:121420. doi: 10.1016/j.carbpol.2023.121420. Epub 2023 Sep 20.

Authors

Akash Balakrishnan¹, Mahendra Chinthala², Rajesh Kumar Polagani³

Affiliations

¹ Process Intensification Laboratory, Department of Chemical Engineering, National Institute of Technology Rourkela, Rourkela, Odisha 769008, India.
² Process Intensification Laboratory, Department of Chemical Engineering, National Institute of Technology Rourkela, Rourkela, Odisha 769008, India. Electronic address: chinthalam@nitrkl.ac.in.
³ Centre for Fuel Cell Technology (CFCT), International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Chennai, Tamilnadu 600113, India.

PMID: 37940252
DOI: 10.1016/j.carbpol.2023.121420

Abstract

Graphitic carbon nitride (GCN) is an efficient visible-light-driven metal-free semiconductor with superior photocatalytic activity. However, the main drawbacks of GCN include lower adsorption capacity, poor reusability and recoverability. To address these drawbacks, kaolinite/g-C₃N₄-alginate beads were fabricated using a cross-linking method to remove brilliant green dye from wastewater via photocatalysis. The characterization studies proved the alginate's potential capability in altering photocatalyst bandgap (2.78 to 2.55 eV) and minimizing recombination of electron-hole pairs. Kaolinite/g-C₃N₄-alginate photocatalyst removed 97 % of brilliant green (10 mg/L) in 90 min under visible light irradiation. The superior performance of the kaolinite/g-C₃N₄-alginate beads was ascribed to its improved adsorption and effective utilization of visible light. The key advantages of kaolinite/g-C₃N₄-alginate beads were their quick recovery and extended reusability upto ten cycles. The sustainability metrics analysis of kaolinite/g-C₃N₄-alginate beads confirmed the environmental suitability and practicability in wastewater remediation. This study provides new insights into the low-cost and sustainable preparation of highly reusable g-C₃N₄-based photocatalysts for environmental remediation.

Keywords: Adsorption; Beads; Photocatalysis; Wastewater; g-C(3)N(4).