Tri-reforming of CH<sub>4</sub> over a Thermally Stable and Carbon-Resistant Nanonickel Metal Catalyst Dispersed on Mesoporous-Zirconia
Akansha Pandey, Prakash Biswas, Kamal Kishore Pant, Ajay K. Dalai
Abstract
A novel nanonickel metal catalyst dispersed on mesoporous-zirconia is developed for the controlled production of the synthesis gas with an H 2 /CO molar ratio of 1.5–2 via the tri-reforming of methane (TRM). The catalysts were tested in a fixed-bed reactor at 600–850 °C and 1 atm. At the optimum feed (CH 4 /CO 2 /O 2 /H 2 O/N 2 ) ratio of 1:0.5:0.1:0.0125:1, the maximum CO 2 and CH 4 conversion was ∼28 and ∼86%, respectively, over the 5 wt % Ni/ZrO 2 . At this condition, the syngas with an H 2 /CO ratio of ∼1.5 was achieved at a lower reaction temperature of 700 °C. The superior activity of this catalyst was due to the presence of highly dispersed and reduced nickel particles over the combined tetragonal and monoclinic phases of mesoporous ZrO 2 . The basic strength of the catalyst, the nickel particle size, and metal dispersion played vital roles in controlling the TRM activity as well as the H 2 /CO ratio. The time-on-stream study and the used catalyst characterization results established that the nanosized nickel metal particles dispersed on mesoporous zirconia were thermally stable and coke-resistant.