Characterization of acid-base catalysts by calorimetric titration: II. Effect of poisoning on titration curves and alcohol dehydration activity

doi:10.1016/0021-9517(75)90094-9

Journal of Catalysis

Volume 38, Issues 1–3, 23 June 1975, Pages 326-334

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Abstract

Several commercial aluminas, silica-aluminas and clays have been subjected to poisoning by ammonia and organic bases and subsequently characterized (1) by calorimetry, yielding the heat of adsorption of bases and acids as a function of coverage (2) activity in ethanol and methanol dehydration reactions. A correlation developed in the previous paper [Bakshi, K. R., and Gavalas, G. R., J. Catal. 38, 312 (1975)] describing the activity of fresh catalysts in terms of their acidity and basicity distributions has been used to describe the activity of the poisoned catalysts. Certain rather subtle selectivity changes caused by poisoning have been explained by the corresponding changes in the acidity and basicity distributions.

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