Thermodesorption studies of energetic properties of nickel and nickel-molybdenum catalysts based on the statistical rate

摘要

The new heoretical approach to adsorption/desorption kinetics, called the statistical rate theory of interfacial transport, is used to analyze quantitatively spectra of hydrogen thermodesorption from alumina-supported nickel and nickel-molybdenum catalysts. A new more accurate method is developed to calculate the distribution of the chemisorptio energies on the surfaces of these two catalysts. The comparison of their adsorption energy distributions shows that the addition of molybdenum, changes relative mutual proportions of th efour kinds of chemisorption sites existing on these catalysts surfaces. Changing these proportions is related to changing tendencies to coking formation and changing tendencies to coking formation and changing activities for methane steam reforming.