N-HEPTANE ISOMERIZATION OVER Pt/TUNGSTATED ZIRCONIA CATALYSTS
Abstract
Platinum supported on tungstated zirconia catalysts were synthesized and evaluated in the n-heptane isomerization reaction. The catalysts were synthesized by surfactant-assisted coprecipitation with recirculation and without recirculation. The synthesis of the catalysts and the characterization results by High resolution transmission electron microscopy (HRTEM), X-ray diffraction and Laser Raman spectroscopy are presented, as well as the results for the catalytic evaluation at different reaction conditions. This work suggests that cracking products were formed mainly of bi-branched isomers of n-heptane and they were favored at high reaction temperatures. Finally, it was observed that use of the catalyst synthesized by reflux decreased the cracking activity, improving the selectivity to higher octane isomers.
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