Dry reforming of methane on Ni-Mg-Al nano-spheroid oxide catalysts prepared by the sol-gel method from hydrotalcite-like precursors

摘要

Nanocapsular hydrotalcites (layered double hydroxides - LDHs) were synthesized by the sol-gel method and used as precursors of nano-structured mixed oxides containing various nickel loads (4, 15 and 19 wt%). The best conditions for the preparation of LDHs were analyzed and the structures of the resulting mixed oxides were studied. The optimal nickel load and calcining conditions were optimized. Finally, the resulting catalysts were tested in the dry reforming of methane for 8 h at 800 ℃ under atmospheric pressure. These materials showed high activity and stability, and the coke deposits were minimal on the catalyst prepared under optimal conditions (19wt% nickel load and thermal treatment at 650℃). The best catalyst formed amorphous carbon, which seems not to be prejudicial to the reaction.