The selection of experimental conditions in temperature-programmed reduction experiments

Abstract

The effect of experimental conditions on temperature-programmed reduction (t.p.r.) profiles has been studied. In the case of t.p.r. curves that include several reduction steps an inadequate selection of these parameters leads to distorted profiles; these distortions may produce a complete loss of resolution for the different reduction steps. A criterion to select appropriate experimental conditions through a simple parameter that relates heating rate (β), sample size (S₀) and hydrogen feed to the reactor (FC₀), is given. Finally, the conditions required to obtain reliable activation energies for the reduction processes from the variation in temperature of the t.p.r. maxima with β, without making any previous assumptions about the reduction kinetics, are discussed.