CO_2 reforming of methane over Ni-Cu/Al_2O_3-ZrO_2 nanocatalyst: The influence of plasma treatment and process conditions on catalytic properties and performance

摘要

Argon glow discharge plasma was applied for treatment of impregnated Ni-Cu/Al_2O_3-ZrO_2 nanocatalyst. The catalytic performance toward CO_2 reforming of methane and the physicochemical properties were investigated by means of GC, BET, XRD, FESEM, TEM, EDX, TG-DTG, XPS and FTIR techniques. The plasma-treated nanocatalyst contains smaller crystal size and high dispersion of NiO. Plasma treatment decreased particle size and plasma high energy species flattened particles on support, increasing the interaction between support and active metals which leads to high catalytic activity. Low temperature activity and H_2/CO ratio closer to 1 was observed for plasma-treated nanocatalyst compared to non-treated sample. Moreover, higher product yield and H_2/CO ratio was found in CH_4/CO_2=1 rather than CH_4/CO_2=1.5. Time on stream test during 1,440 min at 850 ℃ showed plasma-treated Ni-Cu/Al_2O_3-ZrO_2 nanocatalyst did not experience any deactivation in terms of CH_4 and CO_2 conversion and H_2/CO ratio.