This Altamira Note gives a basic background on the measurement of BET surface area as applied to catalysts and catalytic supports as well as discusses the flow techniques for measurement of surface area.
Heterogeneous catalytic hydrogenation is a common reaction in many multistep syntheses of pharmaceuticals and fine chemicals. The commercial scale reactions are typically carried out over supported noble metals in liquid-phase batch reactors under mild conditions of temperature and pressure. For this reason, the characteristics required of the catalyst differ somewhat from those of catalysts used in hydrogenation reactions in the petrochemical industry where high-temperature gas-phase conditions predominate. The most important characteristics are outlined below.
In previous issues of Altamira Notes we have discussed the use of pulse chemisorption and temperature-programmed desorption, i.e. dynamic techniques, for catalyst characterization. One question that is often asked is how do results from these techniques compare with results obtained from static volumetric chemisorption methods? This Note compares results for various catalysts obtained by both static and dynamic methods.