Acid Catalysts From Activated Carbon to n-Pentane Isomerization

摘要

Light paraffin isomerization is performed by platinum-based catalysts and chlorinatedalumina. 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 supportswere impregnated with 0.3 wt % platinum, resulting catalysts Pt /VEGCARB andPt/MINCARB and a second pair was obtained after co-impregnation of 0.3 wt% platinumand 0.3 wt% rhenium, resulting catalysts Pt-Re/VEGCARB and Pt-Rh/MINCARB. All ofthem 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 carbonsin the laboratory and medium acidity sites after the impregnation of metals. The catalystswere tested in the isomerization of n-pentane at atmospheric pressure, resulting selectivityto 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.