Spinel-type MnxCr3-xO4-based catalysts for ethanol steam reforming

[Display omitted] •Phase of Mn-Cr-O cubic spinel is observed when manganese content is 10−65 atomic %.•Ru deposition decreases reduction temperature during H2 TPR by 40−80 °C.•Increased Mn content leads to a higher reducibility of oxides.•Co-deposition of Ni and Ru provided the highest activity in ethanol steam reforming.•High activity in ESR provided by MnCr2O4 cubic spinel support. For catalysts comprised of mixed manganese-chromium oxides MnxCr3-xO4 (x = 0.3–2.7) prepared by Pechini route with Ni and Ru supported by impregnation fundamental factors determining their performance in ethanol steam reforming have been elucidated using combination of structural (XRD, HRTEM), spectroscopic (UV–vis), surface science (XPS, FTIR spectroscopy of adsorbed CO) and kinetic (H2 and EtOH TPR, oxygen isotope heteroexchange with C18O2) methods. The most important feature is strong metal-support interaction stabilizing small clusters of metals/alloys and preventing carbon nucleation. The lattice oxygen mobility and reactivity increased with Mn content. The highest TOF was obtained for (Ni + Ru)–loaded oxide support containing cubic spinel phase of MnCr2O4 composition, which implies a positive effect of Ni-Ru interaction in mixed clusters on catalytic activity. This catalyst has also a high density of active sites, surface enriched by Mn and sufficient oxygen mobility providing coking stability, which makes it attractive for practical application.