Direct Photolysis of 2-Propanol Vapor

Abstract

The photolysis of 2-propanol vapor in the 1800–2000 Å wavelength range has been investigated. The volatile products of the reaction and their quantum yields at 80 °C and 200 Torr substrate pressure are H2 (0.64), CH3COCH3 (0.34), CH4 (0.39), CH3CHO (0.29), CO (0.15), and C2H6 (0.08). A mechanism is proposed that accounts for the observed rate variations with substrate pressure, exposure time, temperature, and pressure of inert addend. Acetone and acetaldehyde undergo significant secondary decomposition and this is the source of CO, CH4, and C2H6. Acetaldehyde is formed in the unimolecular decomposition of C3H7O radicals produced in the primary process.The effects of CO2 and CF4 as inert addends have been examined and it has been established that the quantum yield enhancement through collision induced predissociation that has been reported to occur in methanol is not a characteristic of the 2-propanol photolysis.