Estimation of heat of adsorption from energy distribution on heterogeneous surfaces by a theoretical analysis of adsorption process

Abstract

An attempt was made to calculate theq—θ function (experimental heat function) from theε—θ function (energy level function) of a heterogeneous surface. In order to obtain the heat of adsorption, adsorption was assumed to take place on each energy level of theε—θ function. In reversible adsorption, Langmuir's monolayer model was extended to determine the occupation of energy levels by molecules. On this basis, the heat of adsorption could be calculated. Irreversible adsorption was also examined on the basis of chemical kinetics. Molecules were supposed to be held on sites to which they first collided. These calculations were useful for estimating the extent of deviation of theq—θ function from theε—θ function.