Ni/MgO Catalysts on Structured Metal Supports for the Air Conversion of Low Alkanes into Synthesis Gas

摘要

Heat-resistant, heat-conducting, and selective catalysts based on nickel highly porous foam-cellular material (HPFCM) and a mesh support are developed for the air conversion (partial oxidation) of low alkanes into additives that initiate combustion for fuel supplied to an engine as synthesis gas. The catalysts are developed in several stages: preparing a support based on nickel HPFCM (amount of Ni, 99.95%; PPI = 40) or an FeCrAl mesh; creating the support surface; forming structured blocks; the heat treatment of samples; applying an active component via the repeated co-impregnation of magnesium and nickel acetates; and stepwise heat treatment. NiO-MgO/(HPFCM or FeCrAl) catalysts tested in the air conversion reactions of propane, propane-butane, and natural gas, and in tri-reforming are prepared using this technique. The catalysts exhibit conversion of 90-96% over 80-100 h in all experiments at hourly space velocities of 32 000-71 000 h(-1) and coefficients of air excess of 0.31-0.43 with no formation of coke. A two-phase two-temperature mathematical model of the air conversion of liquefied petroleum gases (LPGs) that is in good agreement with experimental data on the temperatures of the catalyst and flow, and on the composition of the gas mixture at the output, is developed for numerical analysis of the results. Results from calculations for a generator of the air conversion of LPGs at a thermal power of 100 kW are presented as an example.