CATALYST DECOMPOSITION DURING TEMPERATURE-PROGRAMMED DESORPTION OF BASES FROM PROMOTED SULFATED ZIRCONIAS

Results from temperature programmed desorption of ammonia, pyridine, a nd benzene from sulfated zirconia catalysts promoted with Fe, Mn, and Ni are compared. Without adsorbates, catalysts are thermally stable be low 900 K. With adsorbates, catalysts decompose partially or completel y between 700 and 900 K. It is shown that previously reported conclusi ons regarding acid strength distributions for promoted sulfated zircon ia catalysts that were based on the results of ammonia and benzene the rmal desorption studies are likely incorrect because the decomposition of adsorbates and the catalyst were not considered.