Preparation and optimization of Ni-Co/Al2O3-ZrO2 films as catalytic coating on microchannels reactor for methane dry reforming

The catalytic performance of Ni-Co/Al2O3-ZrO2 thin films prepared by physical vapor deposition (PVD) method and by using microchannel reactor was examined in the dry reforming of methane (DRM). First, radio frequency (RF) magnetron sputtering method was used to sputter a layer of Al2O3 on a stainless steel plate, and then zirconia thin films were deposited by thermal evaporation to prepare the bimetallic catalyst support. Subse-quently, (RF) magnetron sputtering method was used to deposit Co doped Ni thin films in various Co percentages on the Al2O3-ZrO2. Using response surface methodology (RSM), deposition time (2, 3, and 4 min), Co/Ni weight percentage (2.5%, 5%, and 7.5%), and reaction temperature (700, 750, and 800 degrees C) were selected as the operating variables to investigate and optimize initial feed conversion, catalyst deactivation, and H-2/CO ratio. XRD, FESEM, and EDX analyses were utilized to explore the characteristics of the nanocatalysts. Under optimum conditions (i.e., the deposition time of 3.97 min, reaction temperature of 800.00 degrees C, and Co/Ni weight per-centage of 4.76%), the initial conversions of CH4 and CO2 respectively were 94.16% and 97.74%. Additionally, the deactivation rate of the catalyst was 1.94% and the H-2/CO ratio was 0.95. The stream test under optimum condition (i.e., P = 1 atm, CH4/CO2 = 1, T = 800 degrees C, GHSV 46000 mL/g h), which lasted 28 h and was used to gauge the stability of the developed catalysts, showed that the catalysts prepared under optimum conditions enjoyed relatively better stability compared to the other ones.

Automated summary

This study investigated the catalytic performance of Ni-Co/Al2O3-ZrO2 thin films prepared by physical vapor deposition (PVD) method in the dry reforming of methane (DRM). The optimized catalyst showed good conversion rate and stability.