Effect of H2 reduction on the catalytic properties of molybdenum oxides for the conversions of heptane and 2-propanol

Conversions of heptane and 2-propanol were carried out using MoO3 reduced with Hz at 623 K. The parent MoO3 was inactive for the isomerization of heptane. Hp reduction, however, enhanced the isomerization activity, which became almost constant after reduction for 2.4h. The reduced MoO3 exhibited a higher isomerization activity than 0.5 wt.% Pt/USY zeolite, while there was no appreciable difference in product distribution between these two catalysts. The catalytic activities of MoO3 for dehydration and dehydrogenation of 2-propanol also increased for longer periods of Hz reduction. NH3-TPD studies showed that the acidity of MoO3 was strongly affected by H-2 reduction. We suggest from these results that H-2 reduction of MoO3 at 623 K generated the bifunctional property, which was responsible for a high isomerization activity. (C) 2000 Elsevier Science B.V. All rights reserved.