Preparation and application of SiO-FeO and SiO-FeO-Fe for soot oxidation: A step toward decarbonization by reducing soot particle emissions.

The article presents a method for obtaining catalytic systems: SiO-FeO, SiO-FeO-Fe and verification of their catalytic properties in the oxidation process of technical soot N550. The process of immobilization of Fe ions on microsilica-SiO was investigated in the batch system (equilibrium, kinetics, thermodynamics). The process was aimed at obtaining a system with a developed surface and using less iron while maintaining the same catalysis active surface. In the next stages, the SiO-Fe systems were modified to obtain SiO-FeO and SiO-FeO-Fe materials, which exhibited catalytic properties. To obtain catalytic systems, the processes of Fe ions sorption, iron oxide precipitation - FeO and Fe reduction using a plant extract were used. Catalytic systems were applied in the N550 technical soot oxidation process to reduce the conversion temperature and increase its efficiency. The soot oxidation process was carried out in a muffle furnace using variable process parameters, i.e. temperature (450, 475, 500, 525 and 550C), time (1, 2 and 3h), type of catalytic system (SiO-FeO, SiO-FeO-Fe) and its % content relative to the constant mass of soot (0, 10, 20 and 30%). The greatest increase in the conversion efficiency of soot particles was obtained using the SiO-FeO system with a content of 20% at a temperature of 550C and for 3 h.