The formation of formic acid upon low-temperature condensation of a methane-carbon dioxide mixture dissociated in a microwave discharge

Abstract

Formic acid was found as the main product upon low-temperature (77 K) condensation of the CH4+CO2 mixture dissociated in the microwave discharge at a low pressure. The yield of HCOOH was studied as a function of the experimental conditions: flow rate of the initial gas mixture. CH4 content in the initial mixture, pressure in the reactor, and output power of the microwave generator. The concentrations of H, O, OH, and O2 in the gas phase were measured by ESR spectroscopy. Mathematical modeling of the kinetics of the gas phase chemical reactions in the connecting channel was performed. The mechanism of formic acid formation by the interaction of active species of the gas phase on the condensate surface was proposed.