Study of the performance of dry methane reforming in a microchannel reactor using sputtered Ni/Al 2 O 3 coating on stainless steel Raziye Rezaei, Gholamreza Moradi * Catalyst Research Center, Department of Chemical Engineering, Razi University, Kermanshah, Iran article info Article history: Received 3 July 2018 Received in revised form 24 September 2018 Accepted 28 September 2018 Available online xxx Keywords: Microchannel reactor RF magnetron sputtering Ni/Al 2 O 3 thin films Sputtering time DRM abstract In this study, a microchannel reactor was designed, its catalytic performance in dry methane reforming (DRM) was assessed, and the results were compared with those observed in a conventional fixed bed reactor. The catalyst was prepared in two forms, including catalyst pellets and catalyst-coated plate. The microchannel reactor had thin films of Ni/Al 2 O 3 coated on stainless steel substrate via radio frequency (RF) magnetron sputtering method in various sputtering times. The fall-off rate of the catalyst-coated plates can be neglected after putting the plates under the high-temperature DRM reac- tion, due to the formation of firm active catalyst coatings. The performance of the samples was evaluated at different temperatures from 700 to 800  C, at P ¼ 1 atm, with a CH 4 :CO 2 ratio of 1. The results of XRD showed that with increasing the sputtering time, there was an increase in crystallinity. As observed in FESEM images, the sample prepared with 5 min of sputtering was dense and uniform. The results of EDX not only proved the dispersion of the samples observed in XRD and FESEM analysis, but also verified the presence of the utilized elements. The temperature of 800  C and the sample with 5 min sputtering time were selected as the optimum condition that provided the best performance. Catalytic perfor- mance was investigated in fixed bed reactor at the same GHSV; based on the results there were no significant conversions in the fixed bed reactor. The results of the stability test in the microchannel reactor showed a good performance during 30 h on stream. Therefore, Ni/Al 2 O 3 thin films had a satisfactory performance in the designed microchannel. Our study shows that this type of reactor has many advantages in terms of performance, compactness, and economic concerns. © 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. Introduction Because of the remarkable decline in fossil fuels and the need for controlling global warming, there is an increasing interest in exploiting sustainable and renewable sources of energy. For several reasons, hydrogen is considered as one of the best alternatives to traditional fossil fuels [1]. DRM is one of the common methods of hydrogen production [2]. DRM is per- formed through the consumption of two major greenhouse gases and is considered as a proper method for the production of synthesis gas. The gas produced via this method has a * Corresponding author. E-mail address: gmoradi@razi.ac.ir (G. Moradi). Available online at www.sciencedirect.com ScienceDirect journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy xxx (2018) 1 e12 https://doi.org/10.1016/j.ijhydene.2018.09.200 0360-3199/© 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. Please cite this article in press as: Rezaei R, Moradi G, Study of the performance of dry methane reforming in a microchannel reactor using sputtered Ni/Al 2 O 3 coating on stainless steel, International Journal of Hydrogen Energy (2018), https://doi.org/10.1016/ j.ijhydene.2018.09.200