Effect of the acidity of impregnation solution on the performance of normal paraffins dehydrogenation catalyst

The influence of the acidity of impregnation solution of hexachloroplatinic acid on the performance of promoted Pt/Al2O3 normal paraffin dehydrogenation catalyst was studied. ThePtInSnLi/Al2O3 catalyst samples were prepared by sequential impregnation method using differentamount of HCl as the competitor corresponding to pH levels of 1.1, 1.2, 1.3, 1.5 and 1.8. Theresulting catalyst samples were characterized by UV and XRF methods. The performance tests for normal paraffins dehydrogenation were carried out in a fixed-bed stainless steel reactor. The results showed that the pH value strongly influence the catalyst properties and performance, withlower pHs improving dispersion at the expense of a lower active metal loading. Catalyst synthesized at pH=1.5 exhibited the best performance in terms of mono-olefin selectivity, due to both a high level of adsorption and high dispersion of Pt atoms.

کلیدواژه ها:

normal paraffins dehydrogenation ، PtInSnLi/Al2O3 ، pH ، adsorption ، dispersion