LAUSR

The interaction of platinum with carbonaceous graphite-like material Sibunit was studied. It was found that carbon covers the platinum particles during the reduction in a hydrogen flow. Chemisorption of CO over such samples has shown that just a small part of Pt surface is opened and accessible for the reagents. The carbon support was additionally pretreated by a high temperature graphitization in nitrogen. The amount of surface oxygen-containing groups was increased by a treatment with nitric acid. An examination of the Pt-loaded samples in hydrogen has revealed that the oxidative treatment does not affect the activity in the carbon hydrogenation process. Both the initial and oxidized Pt-loaded samples facilitate intensive carbon interaction with hydrogen leading to quite similar amounts of methane released. Contrary, the graphitization of the support allows one to minimize the methane formation. Lower specific surface area and absence of amorphous carbon weaken the platinum–carbon interaction and facilitate the formation of larger particles, thus complicating the realization of hydrogenation mechanism.