Technoeconomic Analysis and Life Cycle Assessment of Soft Drink Industry Wastewater Using a Microwave Photocatalysis System

Abstract Microwave-assisted photocatalysis (MWPC) for treating soft drink industry wastewater is evaluated in this study against microwave oxidation (MWO), photocatalysis (PC), and oxidation. MWPC achieved the highest total organic carbon (TOC) removal (87.09%), outperforming MWO (79.75%), PC (23.36%), and oxidation (23.70%). Total nitrogen and total phosphorus removal by MWPC were 5.71 and 4.14 times higher than oxidation, respectively. MWPC achieved the lowest cost per gram of TOC removal (₹29/g) due to its substantially higher TOC removal efficiency compared with other systems. Catalyst reusability over three cycles reduced operating costs by 65%, while maintaining pollutant removal efficiency. Scaling analysis projected a capital cost of ₹2.84 million for a 1 kL/day system. Life cycle assessment indicated the lowest global warming potential of 181.18 kg CO 2 -eq per kg of TOC removed for MWPC, which was 2% and 65% lower than MWO and PC, respectively. The synergy of microwave irradiation and photocatalysis enabled enhanced degradation, lower costs, and reduced environmental impacts, while aligning with multiple UN Sustainable Development Goals.