Acid Catalysts From Activated Carbon to n-Pentane Isomerization

摘要

Light paraffin isomerization is performed by platinum-based catalysts and chlorinated alumina. This study used activated carbon as catalyst support for its high surface area. Four catalysts were prepared from activated vegetal carbon (technical degree, MEYER) and mineral carbon (technical degree, MEYER) by treatment with HNO3-6N. The supports were impregnated with 0.3 wt % platinum, resulting catalysts Pt /VEGCARB and Pt/MINCARB and a second pair was obtained after co-impregnation of 0.3 wt% platinum and 0.3 wt% rhenium, resulting catalysts Pt-Re/VEGCARB and Pt-Rh/MINCARB. All of them were burned in situ for 1 hour at 350 °C in dynamic atmosphere of hydrogen. Potentiometric titration showed the presence of strong acid sites on the activated carbons in the laboratory and medium acidity sites after the impregnation of metals. The catalysts were tested in the isomerization of n-pentane at atmospheric pressure, resulting selectivity to isopentane in the order: Pt/VEGCARB > Pt/MINCARB > Pt-Re/MINCARB > Pt- Rh/VEGCARB, with rates of conversion to isopentane with the following order: Pt- Rh/VEGCARB > Pt-Rh/MINCARB > Pt/MINCARB > P/VEGCARB.