Continuous Manufacturing Process Design of Solid-Waste-Based Ozone Catalysts and Their Long-Term Performance Study
The high cost of catalysts is a critical barrier to the upgrading and cost reduction of catalytic ozonation technology. This study developed a low-cost, long-life Fe–Mn-based ozone catalyst (FMG) derived from solid wastes (red mud and blast-furnace slag), leveraging iron and manganese components to construct dual active centers. A continuous manufacturing process was achieved by integrating alkali-activated cementitious reactions with disc pelletization via a cascade spray-coating and multi-stage curing technique. Under optimal conditions (ozone dosage 3.5 mg·L−1), the catalyst achieved 81.81% total organic carbon (TOC) removal of phenol solution within 60 min, retaining 87.27% of its initial activity after 15 reuse cycles. Long-term continuous-flow tests over 60 days demonstrated stable TOC removal between 69.44% and 75.46%. The production cost of FMG was 1,351.44 CNY·t−1, and the unit TOC removal cost was only 0.06 CNY·(g TOC)−1, representing a 78.69%–86.85% reduction compared to commercial catalysts (0.30–0.48 CNY·(g TOC)−1). This work provides a theoretical and technical foundation for cost-effective catalytic ozonation and high-value conversion of bulk solid wastes.