Reforming of natural gas using coking-resistant catalyst for fuel cell system applications

Abstract A coking-resistant catalyst prepared using a novel catalyst support is characterized and its performance on reforming of natural gas for fuel cell system applications is investigated. Two key issues, i.e., the stability of catalyst under the reforming environment and deposition of carbon on the catalyst surfaces leading to deactivation, have to be resolved. The reforming operations are performed using a modified external autothermal reforming (ATR) approach. Desulfurized natural gas is used as a feedstock to avoid catalyst poisoning and air is exploited as an oxidant. It is found that the reforming catalyst is able to remain stable and free from pulverization at the desired operating conditions when α-Al 2 O 3 is employed as a catalyst support in place of the commonly used γ-Al 2 O 3 counterpart. In addition, the ceria (CeO 2 )-assisted Pt catalyst coated on the α-Al 2 O 3 support, i.e., Pt/CeO 2 /α-Al 2 O 3 , is able to significantly eliminate the coking problem with a CH 4 conversion rate >99% and a generated H 2 concentration ∼62% at 1073 K. A reaction mechanism is proposed to elucidate the coking-resistance of the catalyst, which also accounts for the stability of the catalyst. The reforming catalyst has been tested continuously for 2400 h and is still able to maintain a good operating condition.