Tackling limitations of future relevant thermo-chemical reactions by exploiting the dynamic surface behaviour of complex mixed metal oxides

ongoing

For a sustainable future highly active, selective andFor a sustainable future highly active, selective and stable catalyst are of utmost importance for the chemical industry. The conventional steady-state operation of catalytic reactors reaches its limit. This project opens up new perspectives on the opportunities of tailored oxide surfaces. We aim to develop a dynamic responsive catalysts (DRC) that change their surface structure dependent on the oxidizing or reductive character of the reactant mixture. Combined with oscillation between reducing and oxidizing atmosphere in forced periodic operation (FPO) our concept opens unprecedented opportunities for surface engineering: At low reduction degree, the DRC-FPO concept allows activation and net stabilization of active/selective metastable sites that are thermodynamically not accessible under conventional steady-state operation. Furthermore, at high reduction degrees, the DRC-FPO concept enables reversible formation of highly dispersed active nanoparticles out of the mixed metal oxide host structure. Upon oxidative treatment, the atoms of nanoparticles can reintegrate into the host structure at ultimate dispersion. This is a unique way to overcome irreversible catalyst deactivation by nanoparticle sintering. With our expertize on mixed metal oxides based like spinels and perovskites we will enable the DRC functionality by compositional tailoring and resolve general trends. To leverage the full potential of this approach, we aim to explore all relevant effects in four future relevant demonstrator reactions at low and high temperatures as well as oxidizing and reductive environment by a combination of synthetic, analytic, reaction engineering and operando characterization methodologies. The acquired basic knowledge and proven feasibility of the DRC-FPO concept opens a paradigm-shift in the operation of catalysts. It generates ground-breaking ways to create defined active surface sites and avoid catalyst deactivation.