Hydrogen-based fuel cells for automotive and stationary applications are gaining popularity for various reasons including their higher efficiencies and lower emissions.The infrastructure to deliver hydrogen is currently inadequate and the storage of hydrogen on- board a vehicle remains a major technical and economic hurdle.Use of liquid hydrocarbon fuels to generate hydrogen is being thought of as an immediate solution for large scale hydrogen production.[1]. The conversion of hydrocarbon fuels to syngas and hydrogen can be carried out by several processes,including steam reforming(SR), partial oxidation(PO),and auto thermal reforming(ATR).The choice of the reaction process to be used for on-board reforming depends on many factors,including the operating characteristics of the application(e.g.varying power demand,rapid startup,frequent shutdowns)and the type of fuel cell stack.SR is heat transfer-limited and as such does not respond rapidly to changes in the power demand (i.e.“load following”).SR is currently the predominant industrial method for producing hydrogen.POX and ATR,on the other hand, were developed mainly for small-scale applications or for conversion of heavy feedstocks[2].Inui et al.[4-6]first explored the ultra-rapid thermo-neutral reforming process for natural gas and Liquefied Petroleum Gas(LPG)using a multi-component catalyst. Conceptually,it is similar to the ATR process where two reactions take place in the process.However,the TNR utilizes a novel paradigm where catalytic combustion and steam reforming functions exist on the same catalyst.The heat produced from catalytic combustion induces the endothermic steam reforming of hydrocarbons on the same catalyst surface leading to ultra-rapid reforming.In thermo-neutral reforming process the catalyst-bed temperature theoretically and adiabatically rises to a very high temperature as a result of the fuel combustion.However,in reality, the catalyst-bed temperature is forced to decrease by the large endothermic heat sink of the steam reforming reaction.The catalyst- bed temperature can be maintained at a safe and practical temperature range.Because of this characteristic,the reactor size can be reduced by two orders of magnitude compared to conventional steam reforming method.
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