Catalyst development for steam reforming of methane and model biogas at low temperature

Low temperature steam reforming (400-550 degrees C) for the production of hydrogen offers significant advantages compared to the conventional process. The milder operating conditions lead to lower operation costs and cost of construction materials. Additionally, no CO shift reactor is required due to favorable temperature for the WGS reaction. In this work, we report the catalytic performance of Ni and Rh catalysts supported on La2O3-ZrO2 and La2O3-CeO2-ZrO2 for their application in a multifuel membrane reformer operating at low temperature. The performance of the catalysts is assessed in different operating conditions in methane steam reforming (GHSV, temperature, H2O/CH4 ratio) as well as in reforming of model biogas. Stability tests were conducted up to 90 h on stream (1 bar and 7 bar) and the tendency toward carbon formation was investigated. All catalysts were active in the reforming reactions at 400-550 degrees C and the catalysts supported on La2O3-CeO2-ZrO2 showed superiority in activity and stability probably due to the presence of ceria in the support which contributes to the reforming rate and the resistance to carbonaceous deposits. Ni(10)CeZrLa exhibited remarkably stable performance with minimum amount of carbon formed after 90 h (ca. 0.05 wt%). TPO and TPH analysis of the carbonaceous deposits showed that the dominating type of carbon is highly reactive and can be easily removed by oxidation or hydrogenation at 500 degrees C. This fact makes the catalyst even more promising for the proposed low temperature process, since the catalyst can be hydrogenated by using part of the H-2 production stream without further heating of the reactor. (C) 2015 Elsevier B.V. All rights reserved.