Development of a Rapid Decontamination System for the Nerve Agents

摘要

Catalysts using Ag+ and Fe2O3 as dopants on sodalite, Y zeolite and MCM-41 supports were investigated in order to develop a more efficient and safe catalyst for the photodecomposition of dangerous nerve agents. Ag-sodalite, Ag/Fe2O3-sodalite, Ag-Y zeolite, Ag-MCM-41 and Ag/Fe2O3-Y zeolite were all synthesized by ion exchange techniques and characterized by X-ray diffraction, solid state luminescence spectroscopy, and atomic absorption spectroscopy. The Y zeolite-based catalysts show significant spectroscopic differences between the Ag-doped and the Ag and Fe2O3-doped varieties. Catalyst performance studies involving each of the synthesized catalysts were conducted using carbaryl as the reactant and varying wavelengths of UV light as photon sources for the experiments. Catalyst performance studies were also carried out use nerve agents as the target molecules at the Edgewood Chemical and Biological Center. While catalysts perform differently depending on the excitation wavelength used, the Ag-sodalite catalyst at 280 nm excitation shows the most promise for its efficiency and stability. Also, the inclusion of Fe2O3 as a dopant does not enhance catalytic activity. Reactions using Ag-sodalite at 280 nm excitation involving either sodium bicarbonate as a hydroxyl radical scavenger or D2O as solvent show that hydroxyl radicals may play a role in the reaction mechanism.