Unveiling the role of transition metal catalysts in low-temperature, liquid-phase isopropanol oxidation

Abstract

Driven by the increasing need to optimize industrial chemical reactions through effective catalysts, this study reports the comprehensive oxidation process of isopropanol under liquid phase conditions at subambient temperatures, investigating the catalytic potential of transition metal oxides. The complete oxidation of isopropanol within the liquid phase at reduced temperatures was investigated, employing transition metal oxides as catalysts (Cr2O3, Fe2O3, NiO, and ZnO). These solids were prepared using the sol–gel method and the precipitation method. The results from structural (FTIR, XRD) and textural (BET) analyses were consistent with those reported in the literature. The employed solid substances exhibited favorable catalytic activity for the full oxidation of isopropanol, maintaining a consistent selectivity of 100 %, regardless of the temperature conditions under examination (40, 60, and 80 °C). These catalytic tests reveal that chromium oxide is a typical catalyst for this type of reaction. Furthermore, a kinetic analysis of the reaction was conducted, revealing that the reaction proceeds according to a sequential A-B-C mechanistic pathway. The low values of apparent activation energy for all the solids align with the high initial reaction rates in the studied temperature range. This study revealed the effective role of transition metal oxides, particularly chromium oxide, as catalysts for the total oxidation of isopropanol under liquid phase conditions at subambient temperatures, offering vital insights to enhance efficiency in chemical industrial processes.