Abstract:

In the investigation of the catalytic oxidation of volatile organic compounds （VOCs） using in-situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） , the existence of water greatly influences the recognition of surface species and restrains the catalytic behavior of catalysts. In order to solve this problem, the dehydration effects of concentrated H2SO4, anhydrous CaC1₂ and anhydrous CuSO₄, silica gel, and 5A molecular sieves were compared, and the influence of vacuuming on the removal of gaseous water in the in-situ cell was analyzed. The results show that   temperature and the chosen drier greatly affect the removal of gaseous water;   the dehydration becomes easier at a higher temperature;   different from other driers, 5A molecular sieves exhibit the most excellent dehydration effect and improves the catalytic oxidation to a certain degree; and   vacuuming is feasible in the removal or reduction of gaseous water.

Key words: in-situ diffuse reflectance infrared Fourier transform spectroscopy, water, dehydration, molecular sieve