The effect of the tungsten oxide concentration in Pt/WO3-ZrO2 catalysts on hydroisomerization of the heptane-benzene mixture

The effect of the tungsten oxide content in Pt/WO3-ZrO2 catalysts over the range of 10–35 wt.% on hydroisomerization of the heptanebenzene mixture (80/20, wt.%) was studied. The catalysts with the WO3 content of 15–25 wt.% were shown to have the highest fraction of the tetragonal zirconia phase (t-ZrO2, 87–96%), which allows achieving the highest yield of the sum of heptane isomers, particularly high-octane di- and trimethyl substituted isomers (DTMS), the yield of which reaches 69.4–76.7 and 24.5–27.9 wt.%, respectively. In the presence of such catalysts, the yield of methylcyclopentane is 52.1–61.3 wt.% at the 72.6–90.9 % selectivity of cyclohexane isomerization to methylcyclopentane.