Oxidative Activity of Hydrogen on Nickel and Inconel

Experiments were carried out to determine whether nickel or Inconel are catalytically active for hydrogen oxidation. The work was motivated by the problem of flame flashback and/or inlet preignition in hydrogen-rich syngas fueled premixed/prevaporized gas turbine combustors. The experiments were performed using small resistively heated tubular reactors with matrix isolation/infrared diagnostics. Reactors were manufactured from stainless steel, nickel and Inconel. For the flow conditions studied, the conversion efficiency was about 3% for the nickel reactor and 0.9% for the Inconel reactor. No activity was seen for stainless steel. Comparison with a published surface kinetic reaction mechanism for nickel suggests that the surface oxidation rate of H2 in our reactors is about two orders of magnitude less than for specially prepared surfaces.