Positive-Ion Chemistry: High Yields of Heavy Hydrocarbons from Solid Methane by Ionizing Radiation

Abstract
At 77°K solid methane is polymerized rapidly and efficiently to heavy hydrocarbons by cobalt-60 gamma rays. The product is a viscous oil consisting mainly of saturated and highly branched hydrocarbons containing an average of about 20 carbon atoms per molecule. This would seem to be evidence for positiveion chemical reactions in the solid state analogous to those previously reported to occur in the gaseous state at pressures above 0.01 mm-Hg. It would thus appear that the solar ionizing ultraviolet radiation (about I erg cm-2 sec-1 at the earth) must polymerize methane at an appreciable rate under many likely conditions.