Application of pollutant direct oxidative transfer process (DOTP) for chemical industrial wastewater treatment

Direct oxidative transfer process (DOTP) / technology based on oxidative polymerization pathway of organic pollutants is a hot topic in wastewater catalytic oxidation research and has attracted widespread attention in the environmental filed. However, its practical feasibility and value remain questionable. Herein, we report the first case study for the application of DOTP technology for real industrial wastewater treatment. With a series of investigations, e.g., industrial-scale catalyst production, real wastewater treatment evaluation in a pilot-scale plant, analyses of reaction behaviors, conditions, and pollutant removing pathways, as well as applied procedure design and cost assessment, the application feasibility of DOTP and its costs and performance advantages over conventional Fenton-based degradation mineralization process were demonstrated. In this case, the pollutants in the wastewater were mainly converted into solid products via coupling and polymerization pathways, reducing the amount of oxidant used close to the limit - only 2.25 times the molar amount of the pollutant under the practical conditions. Taking the catalyst dosage (2.69 kg per ton wastewater, disposable), catalyst cost (∼ $ 694 per ton) and subsequent solid product disposal cost into account, the overall treatment costs for eliminating 1000 mg/L of chemical oxygen demand (COD) could be as low as $ 0.84 per ton of wastewater. This work provides direct evidence to validate the applicability of DOTP and lays a solid foundation for its further development and implementation for real wastewater treatment.