Adsorption and reactions of CHCl3 on powdered TiO2

摘要

The adsorption and reactions of CHCl3 on three commercially available TiO2 powders have been investigated by Fourier transform infrared spectroscopy in a gas-solid reaction system. Probably, owing to the difference in surface morphology, CHCl3 is weakly adsorbed on two of the three TiO2 samples at 35 degrees C. But, as the more reactive TiO2 is exposed to CHCl3 at 35 degrees C, the surface is found to be covered with CHCl3, HCOO, H2O, and CO. In addition to these surface species, gaseous HCl and CO are generated at higher temperatures. Photoirradiation of CHCl3 on TiO2 in the absence or presence of O-2 causes the decomposition of CHCl3. This photoprocess is enhanced in O-2.