Effect of the active metal on the catalytic activity of the titanate nanotubes for dry reforming of methane

• Decoration of Co or Ni into titanate nanotubes and partial incorporation of Pt.
• Transformation of titanate nanotubes during dry reforming of methane.
• Catalytic activity affected by the nature of the active sites.
• Surface Ni° sites on NiTiO3 exhibited high CH4 and CO2 conversions.

The incorporation of either Co or Ni into titanate nanotubes as well as impregnation of Pt on TNTs were observed in this work. The as-synthesized titanate nanotubes, obtained by hydrothermal method, were in situ transformed during dry reforming of methane. All the spent solids were characterized to show the active phase formed during the reaction and the results demonstrated that the catalytic activity was affected by the nature of the active sites. Surface Ni° sites on NiTiO3 formed from NiTNT exhibited high CH4 (30%) and CO2 (35%) conversions at 600 °C with no deactivation along the reaction time. The nanosized PtOx particles from PtTNT was lesser susceptible to coking, although sintering remarkably decreased the performance of the solid. On the contrary, severe carbonaceous deposition on Co°/CoTiO3 was suggested to be responsible for the deactivation of the solid in dry reforming of methane.