(242f) Catalytic Decomposition of Dimp on Metal Oxide Surfaces Formed from the Decomposition of Composite Crystals

Catalysts are an essential part of most industrial reactions and as such there is a demand to meet many niches. One niche is the in-situ catalyst formation and reactivity for decomposing chemical warfare agents. This work demonstrates the synthesis of different coordination compounds formed from various metal salts and fuels, that will react to form a metal oxide catalyst. This work focuses on the formation of MgO and Al₂O₃. The synthesized catalysts have relatively high specific surface areas compared to materials also reacted using the self-sustained high-temperature synthesis method. The formed catalysts have also been examined using XRD, FTIR, and SEM providing a comprehensive characterization. Then the reactivity against a chemical warfare agent surrogate diisopropyl methyl phosphonate (DIMP) was considered, which is used for its similar structure and behavior to different phosphate-based weapons. Using UV-VIS, the chemical concentrations over 24 hours were monitored and decomposition rates were determined for the different catalysts. The decomposition of DIMP was consistent across synthesized and commercial alumina at 9.8 x 10^-6 g/m²/minute . Magnesium oxide demonstrated a reaction rate 2.8x faster than alumina per m² catalyst with the overall reaction rate favoring alumina due to surface areas over 3.5x greater than that of magnesium oxide. The reactions appear to cleave the isopropyl groups forming propanol which then continues to react on the metal oxide surface forming propene that then leaves in the gas phase. This conclusion is supported by examining wetted MgO versus unwetted MgO where the wetted material had an accelerated reaction rate 2.3x faster than the unwetted MgO, demonstrating some effect from the increased hydroxyl groups present on the surface. This work serves to provide both a route for in-situ catalyst formation along with advancing the understanding of the reaction occurring for the decomposition of chemical warfare agents.