Promising Directions in Chemical Processing of Methane from Coal Industry. Part 3. Catalytic Tests

For the processing of coal mine methane into hydrogen-containing gas, a catalytic process of methane tri -reforming (CH 4 + O 2 + CO 2 + H 2 O) was proposed and its component reactions were studied - partial oxidation (CH 4 + O 2 , POM), dry reforming (CH 4 + CO 2 , DRM) and steam reforming (CH 4 + H 2 O, SRM) of methane. Promoted nickel supported on aluminum oxide was used as a catalyst. Experiments were carried out by varying temperature (600-850 degrees C), contact time (0.04-0.15 s), linear feed rate (40-240 cm/min) and composition of the reaction mixture (POM - CH 4 : O 2 : He = 1 : (0.5-0.7) : (3.3-3.4); DRM - CH 4 : CO 2 : He = 1 : (0.8-1.4) : (2.6-3.2); SRM - CH 4 : H 2 O : He = 1 : (0.8-2.0) : (2.0-3.2)). Optimal reaction conditions were determined to ensure maximum efficiency of hydrogen production by reforming methane-containing mixtures of various compositions (temperature in the range of 800-850 degrees C, contact time 0.15 s, linear feed rate 160 cm/min, molar ratio of CH 4 : O 2 = 1 : 0.5 for POM, CH 4 : CO 2 = 1 : 1 for DRM and CH 4 : H 2 O = 1 : 1.1 for SRM). The degree of catalyst carbonization during the reactions was reduced (from 3 to 1.5% for POM, from 20.7 to 2.2% for DRM, and from 15.2 to 0.4% for SRM) due to an increase in the O/C molar ratio in the initial reaction mixture. Regulation of H 2 /CO molar ratio was achieved over a wide range (0.9-6.5). It has been shown that the hydrogen concentration in the resulting hydrogen-containing mixture is determined by the type of process and is equal to 30 +/- 5 vol.%.