Zr-enhanced stability of ceria based supports for methane steam reforming at severe reaction conditions

Abstract

Ceria based supports are an interesting choice for methane steam reforming due to their coke precursor's gasification activity and ability to stabilize nickel particles. However, sintering and coking studies with this type of catalysts is lacking, particularly at low temperature (600 °C) and low water/methane feed ratio (R ≤ 2). In this work, nickel catalysts supported on an optimized Zr-doped ceria were tested for methane steam reforming at various water/methane feed ratios and contact times. Zr addition improved both sintering and coking resistance; as studied separately by means of XRD and CH 4 -TPSR followed by O 2 -TPO and self-decoking experiments. Carbon deposition/gasification mechanisms on ceria based supports were discussed. Optimized Ni[sbnd]Ce[sbnd]Zr formulation was proven to be a highly stable catalyst for methane steam reforming at the conditions mentioned above.