CATALYTIC GASIFICATION OF CARBON USING IRON.

The rate of catalytic gasification of graphite with an iron catalyst was studied using controlled atmosphere electron microscopy (CAEM). The gas feed to the catalyst-carbon specimen was a mixture of ethane and steam which can lead to either gasification of the substrate or deposition of carbon on the sample. The regime wherein the graphite support was gasified was studied in detail. Fresh samples which had not been heated to temperatures above 975 C were more active than samples which had been heated above this temperature in the reaction mixture. Mossbauer spectroscopy indicated that the change in activity could be attributed to the transformation of iron from the low temperature body-centered cubic crystal (alpha) form to the face-centered cubic (gamma) form. When gamma iron was applied directly to graphite the lower activity was observed despite the thermal history of the sample.