Detailed reaction kinetics of thermo-catalytic direct hydrogen peroxide synthesis using a CSTR for scale-up and process evaluation

• Applicant: Professor Dr.-Ing. Jörg Sauer
• Subject Area: Chemical and Thermal Process Engineering
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 525028514

H2O2 is a specialty chemical with a wide range of applications in water treatment, cleaning, bleaching, disinfection, and the chemical industry. Customer applications vary widely in terms of the amount consumed at the point of use, from household applications to use as an intermediate in large-scale chemical processes. Although the classical anthraquinone autoxidation (AO) process is technically very complex and can only be realized in cost-intensive production plants, it has the advantage that the hydrogen and oxygen feed streams are spatially separated and only connected by the working solution in which the anthraquinone is dissolved. This leads to a very high hydrogen-specific H2O2 yield (> 95%). The thermo-catalytic direct synthesis (t-HP) offers the potential that the industrial implementation is much less complex than the AO process, but feeding H2 and O2 into a single reactor is highly demanding in terms of process safety, design of catalyst, and reactor technology. An in-depth understanding of the spatially resolved reaction kinetics under steady-state and transient conditions is necessary for the targeted development of the catalyst and reactor. This information can be obtained in a continuously operated ideally mixed laboratory reactor (CSTR). For this purpose, a CSTR test rig planned at the IKFT will be used for the investigation of t-HP. Based on the experimental results obtained in the CSTR, approaches for the kinetics of the t-HP reaction will be developed and experimentally parameterized in cooperation with the Studt group. This work will serve as a basis for comparing the micro kinetics of thermo-catalytic and electro-catalytic processes. In addition to the influence of solvent and ion content, the stability of the catalysts under different reaction conditions will be investigated. The reaction kinetics will be used to scale up the t-HP process to an industrial scale. The modeled plant operation data will provide the basis for techno-economic analysis (TEA) as well as life cycle analysis (LCA) in comparison to the conventional AO process. This research will be conducted by Dr. Amit Kumar's group at the University of Alberta in collaboration with my group. The differences in costs of raw materials, investment, and logistics as a function of location factors are interesting applications of LCA and TEA. This research will provide an important basis for guiding fundamental research on catalysts and reactor technology for direct H2O2 synthesis.

• DFG Programme: Research Units
• Subproject of: FOR 5715: Bridging Concepts in Thermo- and Electro-Hydrogen Peroxide Catalysis (HyPerCat)
• International Connection: Canada
• Co-Investigators: Dr. Karla Herrera Delgado; Dr. Stephan Pitter
• Cooperation Partner: Professor Amit Kumar, Ph.D.