1792. ---------------. [KLYUKVIN, N. A. AND KLYUKVINA, S. S.] [Conversion of Methane. II.] Jour. Chem. Ind., U.S.S.R., vol. 7, 1930, pp. 877-885; Chem. Abs., vol. 25, 1931, p. 4520-4521.

Return to Abstracts of Literature 1750-1999

Literature Abstracts

Conversion of CH₄ with H₂O was carried out in an Fe tube 100 cm. long and 22 mm. in diameter. As catalysts reduced NiO (16 gm.) and NiO (24 gm.) were used. The gas mixture consisted of 1 vol. of CH₄ and 4 vol. of steam and was passed with a velocity of 6 liter/hr. The conversion is based on the formula CH₄+H₂O=CO+3H₂, which at low temperature may be modified to: CH₄+2H₂O=CO₂+4H₂, while the interaction of the reaction products may be as follows: CH₄+CO₂=2CO+2H₂ and H₂O+CO=CO₂+H₂, all of which is substantiated by the composition of the resulting gas. The best result obtained is 98.4% conversion of CH₄ with 218% increase in volume, the gas containing CO₂ 5.8, CO 12.6, H₂ 80, O₂ 0.4, N₂ 0.7, CH₄ 0.5% and no unsaturated compounds. A substitution even in part of Al₂O₃ or reduced Fe for Ni produced unsatisfactory results. Activated vegetable C gives 100% conversion of CH₄ at 800° with 142% increase in volume, while the respective figures for reduced Ni at 800° are 33.3 and 100%. At lower temperature (500°-700°) both catalysts give about equal conversion of CH₄, but the quantity of gases obtained is higher with C; this indicates that the conversion of CH₄ is accompanied by decomposition of water: C+2H₂O→CO₂+2H₂. AT 700° the resulting gas mixtures contain 1.2% of CO₂ with Ni and 10.4% with C. It must be noted, however, that the increase in vol. is 142% with C and 218% with Ni. The conversion of CH₄ with C catalyst without H₂O results at 800° in 26.9% and at 900°-950° in 100% conversion of CH₄ with 100% increase in vol. The gas is of exceptional purity, containing CO₂ 0.2, CO 0.8, H₂ 93.1, N₂ 5.9% and no O₂, CH₄ or unsaturated compounds. To investigate more closely the catalytic action of activated C in the thermal conversion of CH₄, the last 2 experiments were repeated with C in porcelain tubes instead of Fe tubes, thereby eliminating any possibility of the catalytic action by Fe. Since the velocity of the gas was 6 l./hr. instead of 3 l./hr. as in the experiments with Ni, it can be concluded from the results that C is a less active catalyst than Ni. With Ni the reaction begins at 300° and reaches a complete conversion of CH₄ at 850°, while with C it starts only at 500°-600°, and ends with only 62.4% of conversion at 1,000°. The test with inactivated birch C under these conditions produced at 1,000° 47.1% conversion of CH₄ in a porcelain tube, and 100% conversion with 100% increase in vol. at 900° when conducted in an Fe tube; that is, equal in its activity to activated C. From 27 gm. of C used 26.8 gm. were recovered after 8 experiments. A catalyst containing 9 gm. of inactivated birch C and 72 gm. of Fe filings produced in a porcelain tube at 1,000° 100% conversion of CH₄ with 100% increase in vol., the gas containing H₂ 97.5, N₂ 2.5% and no other products. The results are similar to those obtained with Ni and with C in an Fe tube. No decrease in weight of the catalyst was observed after 9 experiments.