Isomerization of n-heptane over Pt-loaded zeolite beta catalysts

The influence of key parameters in the isomerization of n-heptane over Pt-loaded H beta catalysts was studied at temperatures lower than 250 degrees C under atmospheric pressure. The highest yield of isomerized products was obtained at 210 degrees C. The conversion of n-heptane increased with contact time (W/F), while the selectivity to isomers decreased. The higher the hydrogen partial pressure, the higher the selectivity to isomers. It was found that Pt/H beta catalyst showed a good stability for 78 h at the reaction temperature of 220 degrees C. The effect of metallic sites and acid sites (Si/Al ratios) on the catalytic property was studied. The higher the content of Pt, the higher the selectivity to isomers, and the lower the acidity of zeolite beta, the higher the selectivity to isomers at the same conversion.