Rajamani Manju, Ganesh Masilamani, Bernaurdshaw Neppolian*

Cite this article: https://doi.org/10.1016/j.cjsc.2025.100845

Publication date:

Keywords: Tetracycline; Zeolitic imidazole framework; Cobalt tungstate; Sonophotocatalytic degradation; Wastewater remediation; Continuous-flow reactor; S-scheme heterojunction.

ABSTRACT

The rapid pace of industrialization has resulted in the alarming discharge of detrimental chemicals into the environment, prompting the scientific community to rethink conventional wastewater treatment technologies. Sonophotocatalysis, a synergistic green approach, harnessing the combined forces of ultrasound and visible light, has emerged as a promising frontier in environmental remediation. Leveraging the exceptional surface area, porosity, and coordination flexibility of Zeolitic Imidazole Frameworks (ZIF-67), a type of Metal-organic framework (MOF), makes it an excellent scaffold for catalyst design. Forming the core of this approach, a CoWO4-decorated ZIF-67 hybrid nanocomposite was developed and utilized as a sonophotocatalyst to degrade tetracycline (TC) under dual-energy exposure. The CoWO4/ZIF-67 catalyst achieved an unprecedented TC degradation efficiency of 98% within 75 minutes, outperforming standalone sonocatalytic and photocatalytic treatment, with excellent reusability. Mechanistic insights, supported by theoretical studies, revealed a strong interaction between the structural and physicochemical properties of the catalyst and energy-induced reactive oxygen species (ROS) generation. A large-scale continuous-flow sonophotocatalytic reactor of 20 L was fabricated to evaluate the performance of the synthesized catalyst on real wastewater samples containing interfering ions. The system achieved an 85% reduction in total organic carbon (TOC), demonstrating excellent scalability and practical applicability, offering a promising approach for treating emerging organic pollutants in an efficient and environmentally friendly manner.