An analysis of the literature data indicates a wide front of research and development in the field of the use of methane–hydrogen mixtures as a promising environmentally friendly low-carbon fuel. The conclusion of most works shows that the use of methane–hydrogen mixtures in internal combustion engines improves their performance and emission characteristics. The most important aspect is the concentration of hydrogen in the fuel mixture, which affects the combustion process of the fuel and determines the optimal operating conditions of the engine. When using methane–hydrogen mixtures with low hydrogen content, the safety measures and risks are similar to those that exist when working with natural gas. Serious logistical problems are associated with the difficulties of using the existing gas distribution infrastructure for transporting methane–hydrogen mixtures. It is possible that, despite the need for huge investments, it will be necessary to create a new infrastructure for the production, storage and transportation of hydrogen and its mixtures with natural gas. Further research is needed on the compatibility of pipeline materials with hydrogen and methane–hydrogen mixtures, safety conditions for the operation of equipment operating with hydrogen or methane–hydrogen mixtures, as well as the economic and environmental feasibility of using these energy carriers.

Growing concern about climate processes has caused an interest in low-carbon fuels, such as methane and hydrogen. Although hydrogen seems to be beyond comparison in this regard, the need for high energy consumption for its production—mainly due to the same fossil hydrocarbons, low specific volume energy, and problems with its storage and transportation—make the production and consumption in the “hydrogen energy” chain extremely expensive, and even environmentally unattractive. Estimates show that it is significantly inferior to methane-based energy not only in terms of costs and efficiency, but also in terms of global CO₂ emissions. The vast resources of natural methane, primarily gas hydrates, are able to provide humanity with energy and hydrocarbons for hundreds of years. Meanwhile, promising modern technologies for the conversion of methane into basic chemicals—including new autothermal technologies for its oxidative conversion into syngas and its direct conversion into chemicals—allow the consideration of methane not only as a fuel, but also as the basis of future organic chemistry. Methane and other hydrocarbons, synthesized using thermonuclear energy from CO₂ and water—which are abundant on the Earth—can remain the most convenient mobile, easily stored and transported fuels and universal chemical raw materials, even after the inevitable transition to thermonuclear energy in the distant future. The inclusion of CO₂ through the synthesis of methane into the global energy cycle will allow real global carbon neutrality to be achieved.

In the range of 800–1200 K, both experiments and kinetic modeling demonstrate a significant difference in the dependence of the ignition delay time of methane and hydrogen on pressure and temperature, with the complex influence of these parameters on the autoignition delay time of methane–hydrogen–air mixtures. In connection with the prospects for the widespread use of methane–hydrogen mixtures in energy production and transport, a detailed analysis of their ignition at temperatures below 1000 K, the most important region from the point of view of their practical application, is carried out. It is shown that such a complex behavior is associated with the transition in this temperature range from low-temperature mechanisms of oxidation of both methane and hydrogen, in which peroxide radicals and molecules play a decisive role, to high-temperature mechanisms of their oxidation, in which simpler radicals dominate. A kinetic interpretation of the processes occurring in this case is proposed.

This paper describes the study of self-ignition delays of stoichiometric binary, triple, and multicomponent mixtures of methane with the addition of up to 10% of normal C2-C6alkanes in air at...

The potential wide use of environmentally friendly low-carbon gas fuel based on natural gas, hydrogen, their mixtures, and syngas in power generation and transport requires detailed information about the kinetics of ignition of these gases at temperatures below 1000 K, at which fuel ignition occurs in internal combustion engines (ICEs) and gas turbines. The same temperature range is also important for monitoring the storage and transportation conditions of these fuels. Although there are quite a few studies addressing the ignition of classical gas fuels such as methane or hydrogen, there is an obvious lack of works dealing with real natural gases and gas mixtures. Furthermore, even for methane and hydrogen, data on the ignition at high temperatures (T > 1000 K), which have been mainly gained by the shock-wave method for highly diluted mixtures, are at variance with the kinetic estimations for real conditions of operating with them or their use in ICEs. Considering the ignition characteristics at T < 1000 K is also important for syngas, the largest-scale base product of gas chemistry and the main industrial source of hydrogen. The pronounced discrepancies between the extrapolation of the results obtained for high-temperature ignition to lower temperatures and the results of kinetic modelling of these processes make it necessary to analyze their causes. This review addresses new experimental results on the ignition of methane–alkane and methane–hydrogen mixtures (real gas fuels) and kinetic modelling of these processes, which reveal significant changes in the ignition behaviour at T < 1000 K. These changes in the ignition process upon the variation of the temperature, pressure, and composition of the mixture are related to significant changes in the methane and hydrogen oxidation mechanisms in this temperature range. They are mainly caused by changes in the kinetics and, hence, the role of peroxide compounds and radicals in methane and hydrogen oxidation following temperature and pressure variation. The established features bring about the question of the adequacy of the existing criteria for assessing the knock resistance of gas engine fuels, primarily those containing hydrogen, when they are used in ICEs, and for assessing their explosiveness and measures taken for their safe handling. The review considers the possible methods for improving the knock characteristics of natural and associated gases to meet the requirements of power equipment manufacturers. The bibliography includes 128 references.