Distribution of reaction products in the koh initiated low temperature steam gasification of graphite

摘要

Powdered graphite samples loaded with various amounts of KOH have been reacted with atmospheric pressure of steam in the temperature range 700–900 K. Significant amounts of C1 to C6 hydrocarbons are found in the gaseous products of this reaction. Both the abundance of these hydrocarbons with respect to hydrogen and their relative distribution vary as a function of reaction time, KOH loading and temperature. A model for their production is proposed according to which C-H groups are stabilized by the formation of a potassium phenolate type compound at the prismatic edge of graphite. Hydrocarbon would then be produced from the direct hydrogenation of surface carbon atoms. The hydrocarbon distribution shows some deviation from the ideal Schulz-Flory distribution, giving little support to a chain growth type mechanism.