V. S. Arutyunov

Gas-phase oxidative cracking of ethane in a nitrogen atmosphere

The gas-phase oxidative cracking of ethane in very dilute gas mixtures ([C2H6]0 ≤ 10%) has been investigated at atmospheric pressure, temperatures of up to 750°C, reaction times of up to 4 s, and initial reactant ratios of [O2]0: [C2H6]0 = 0.2–1.

Effects of the gas medium and heterogeneous factors on the gas-phase oxidative cracking of ethane

The effects of the gas medium and heterogeneous factors on the gas-phase oxidative cracking of dilute ethane mixtures at atmospheric pressure, temperatures of up to 750°C, and an initial reactant ratio of [C2H6]0/[O2]0 = 2 have been investigated.

Partial gas-phase oxidation of hydrocarbon gases with an adjustable methanol-to-carbon monoxide ratio in the oxidation products

Experimental results on the partial oxidation of methane-ethane and C1–C4 alkane gas mixtures are reported. The effect of the parameters of the process on the methanol-to-carbon monoxide ratio in the reaction products is examined and the possibility to control this ratio, important for the subsequent carbonylation of the products, is demonstrated.

Production of gas mixtures with regulated ratios between ethylene and carbon monoxide by the gas-phase oxidative cracking of light alkanes

It was found that, in the gas-phase oxidative cracking of C2-C5 light alkanes, the ratio between ethylene and CO in the products depends on both the residence time in a reactor and the process temperature. This is due to a change in the contributions of product formation and/or consumption channels with increasing the conversion of the reactants. However, the hydrocarbon/oxygen ratio is the main parameter responsible for the limiting ratio between these products reached in the region of deep conversions of both of the reactants. The channels of formation and, correspondingly, the composition of the main products of oxidative cracking change on going from ethane to n-pentane. In this case, the ethylene: CO ratio increases due to an increase in the concentration of ethylene in the products as the number of carbon atoms in the initial alkane molecule is increased at a constant alkane: oxygen ratio. In the oxidative cracking of the C2+ alkane constituents of natural gases, it is necessary to consider the influence of methane, which inhibits the oxidative conversion of heavier alkanes in comparison with their oxidation in an inert gas atmosphere. This leads to a significant decrease in the conversion of oxygen and an increase in the ethylene: CO ratio in the reaction products.

Effect of the concentrations of methane and ethylene on the composition of the products of their cooxidation

The influence of the ratio of the reactants on the characteristics of the cooxidation of ethylene and methane in a two-section flow reactor is examined. It is shown that the radical oxidation of ethylene implicates methane into the oxidation process. The interaction of the thereby formed methyl radicals with ethylene leads to a significant increase in the yield of propylene, an effect that enables to consider the co-oxidation of ethylene and methane as a promising method for producing propylene. A methane-rich flame stabilized on the surface of a flat permeable matrix is proposed as a more efficient source of methyl radicals for converting ethylene into propylene.

Effect of oxygen concentration on the oxidative conversion of propane

The influence of the initial concentration of oxygen and temperature on the oxidative conversion of propane in a two-sectional flow reactor at constant pressure and contact time was studied. It was shown that an increase in the initial concentration of oxygen not only increases the conversion of propane, but also affects the ratio of the reaction products. The yield of ethylene and propylene was found to depend on the initial propane to oxygen ratio and reaction temperature.

Oxidative conversion of hydrocarbon gases in the surface combustion mode

An increase in the natural gas fraction produced from low-debit unconventional resources requires new small-scale technologies for its transportation, conversion to chemicals, and ecologically safe use in power production. A technology of flameless combustion and partial oxidation of natural gas in combustors or converters with permeable volumetric matrix is proposed as an efficient method for the solution of these problems.

Perspective tendencies in development of small scale processing of gas resources

Abstract This paper analyses alternative routes for production of chemicals from different hydrocarbon gases by their direct, without syngas production, oxidative conversion to oxygenates or ethylene. Main of these routes are direct oxidation of methane to methanol (DMTM) and selective oxy-cracking of heavier natural or associated petroleum gas components which can be used for production of high value-added petrochemicals (in combination with carbonylation processes) and fuel gases, useful for gas piston engines. The advantages and practical capabilities of such technologies are discussed.

Activation of the radical-promoted conversion of light hydrocarbons by the products of a rich methane flame

The feasibility of the production of ethylene and heavier olefins by introducing methane into the products of a rich methane flame is experimentally demonstrated. Such a process is promising for the direct production of ethylene, propylene, and heavier olefins directly from methane, the main component of natural gas.

Experimental studies of natural gas to synthesis gas converters based on permeable cavity matrices

The matrix conversion of natural gas into synthesis gas, in which the autothermal oxidation occurs in the surface combustion mode in a cavity of a closed three-dimensional matrix made of a gas-permeable material, was studied experimentally. The specific volumetric productivity of such converters considerably exceeds that of traditional types of converters and allows conversion of hydrocarbon gases of virtually any composition into synthesis gas. Prospects for practical use of the new type of converters are discussed.