The features of combustion of hydrogen and methane in oxygen and air in the presence of difluorodichloromethane additives

Abstract

It is shown that the inhibitor limit of ignition of the premixed methane-air mix makes 1 vol% difluorodichloromethane at 1 atm. It means that difluorodichloromethane is an effective inhibitor to prevent undesirable ignition of methane-air mixes at atmospheric pressure. It is experimentally shown that the concentration limits of the initiated combustion known from literature are meaningful only for previously prepared mixes. If the mixes are prepared just before the experiment, then the existence or the lack of ignition is determined by both an order of injection of mixture components, and the geometry of an installation. Therefore, the inhibition with halons can hardly be used to address the challenges of safety in mines. Thus, the influence of gasdynamic factors on the efficiency of inhibition is revealed. It is shown that the active centers of hydrogen and methane combustion determining the development of combustion process have the different chemical nature. Vibrationally excited molecules of hydrogen fluoride (ν = 2, 3) are for the first time detected in the products of combustion of hydrogen and methane in the presence of difluorodichloromethane by means of hyper spectrometers of visible and near infrared spectral range. It can be promising phenomenon in laser chemical applications. It is shown that in methane oxidation, the reaction with difluorodichloromethane leading to the formation of hydrogen fluoride (ν = 2,3) has to include the active center of methane combustion.