Engineering Innovations in Photocatalytic Systems for Treating Liquid Effluents: A Case Study on ZnO:Co Thin Films

Photocatalytic systems have gained significant attention as a sustainable and efficient technique for treating liquid effluents, thanks to advanced materials and novel technical solutions. Many studies illustrate the practical application of these technologies in the degradation of persistent organic pollutants such as pharmaceuticals, insecticides, and dyes, with high removal efficiencies. In a case study, cobalt-doped zinc oxide (ZnO) films that were prepared using the spray pyrolysis method showed improved photocatalytic activity for rhodamine B (RhB) degradation in the presence of visible light. This case study further validated the potential of cobalt-doped ZnO films for practical wastewater treatment by highlighting the significance of pilot-scale reactor design and modeling, and optimizing the process for large-scale applications using Aspen Plus simulations. Pilot-scale installations highlight the viability of photocatalytic systems for practical uses, emphasizing their energy efficiency and versatility in handling different types of liquid effluents. Continued research in reactor engineering and materials science is necessary to overcome challenges related to long-term stability and operational costs.