chapter  17
44 Pages

The Effects of Finishing and Operating Conditions on Pt Supported Catalysts during CO Oxidation

WithEduardo E. Wolf

Working Surface ......................................................................... 442 Acknowledgments.................................................................................................. 443 References.............................................................................................................. 443

One of the least discussed catalyst preparation variables in the literature is the effect of pretreatment and the reaction environment on the resulting catalyst. Such operations, known in industry as catalyst finishing, are in many cases the key to activity and selectivity. This information is often not disclosed along with bulk compositions in the patent literature and is subject to secrecy agreements between catalyst manufacturers and users. In the open literature, catalyst pretreatment is often copied from existing recipes without major investigation of its effect in the final activity. For this reason, it is not uncommon to encounter widely different results on the activity of catalysts that are apparently similar. In addition, a less known effect in catalysts’ performance is the effect of the reaction environment, which often modifies the surface to conditions quite different than that of the fresh catalyst. This is known in the industry as the lining up of the catalyst’s activity. Interestingly, it is not uncommon for researchers to quote studies conducted under quite different conditions in terms of the type of material and the pressure and temperature used, to compare them with their results obtained under a completely different environment.