Synthesis of high-Btu gas in a Raney nickel-coated tube-wall reactor. [Practically complete conversion of 3:1 molar H/CO ratio synthesis gas to high Btu gas (methane)]

A tube-wall reactor with a Raney nickel catalyst deposited on the outer wall of the tube by flame spraying is effective in the practically complete conversion of 3H/sub 2/ + 1CO synthesis gas to a high-Btu gas (methane) at an hourly space velocity of 7,000 volumes of gas (NTP) per hour per volume of annular volume. Partially reacted synthesis gas containing an appreciable amount of methane can also be treated in this reactor to increase the heating value to over 900 Btu/cubic ft. Excellent heat removal through the metal wall to a coolant and temperature control were obtained. The heat transfer coefficient from the catalyst to the coolant was about 275 Btu/h per square ft//sup 0/F. Synthesis tests were conducted with tubes 1.2 in. in OD by 6 in. long, and 1.3 in. in OD by 36 in. long. When operating at a synthesis gas rate of 100 to 120 scfh/ft/sup 2/ of catalyst-coated tube, catalyst life was long enough to realize a catalyst coat for the raw Raney Ni alloy of about 0.3 cent per 1,000 cubic ft of pipeline gas (900 to 950 Btu/scf). Gas recycling at ratios of 1:1 to 3:1 was effective in increasing conversion andmore » in extending the life of the catalyst to about 16 weeks. In cost and in operating characteristics the tube-wall reactor compares favorably with the fluidized-bed and hot-gas-recycle reactor systems for the synthesis of high-Btu gas from H/sub 2/ + CO. 9 figures.« less