A new method of analysing temperature programmed desorption (t.p.d.) curves measured at different heating rates has been developed. The activation energy for desorption (Ed) and pre-exponential factor (A) have been evaluated at constant coverages by a minimization procedure for ethanol, n-hexane, n-octane, and p-xylene ZSM-5/silicalite-1 pairs. The t.p.d. curves were recorded on a conventional thermogravimetric balance interfaced to a microcomputer, which was used for both data collection and analysis. The Ed values compare favourably with published isoteric and calorimetric heats of adsorption. Advantages of this method are the rapidity of data collection and ease of analysis. The quantitative desorption information obtained could be of valuable assistance to catalyst screening for the characterization of sorbent-sorbate interaction, and in particular to the study of zeolitic acid sites by ammonia desorption.
- Temperature programmed desorption
ASJC Scopus subject areas
- Environmental Science(all)