Integrated fuel processor built on autothermal reforming of gasoline: A proof-of-principle study

One stand-alone integrated fuel processor, which not only incorporated three reaction zones, i.e., an autothermal reformer, a high temperature water gas shift (WGS) reactor and a low temperature WGS reactor, but also thermally coupled with embedded heat exchangers was developed and tested at a 1 kW scale using commercial gasoline and its surrogate n-octane as a hydrogen generator for fuel cell application. Mass and heat management was explored to obtain optimized temperature profiles for individual reaction zones and maximize hydrogen productivity by ensuring complete reforming of hydrocarbons, resolving the trade-off between the enhanced kinetics and the undesirable thermodynamic disadvantage of WGS reaction at high temperatures, and above all recuperating residual heat to realize higher thermal efficiency systematically. The comprehensive effect of some important independent variables on temperature profiles, hydrogen yield and CO purification were investigated, including O2/C and H2O/C molar ratios, fuel types and their throughput, and water allocation. A hydrogen yield of 1.5 mol-H2 mol-C−1 was obtained using octane as source fuel, whereas only 1.1 mol-H2 mol-C−1 for commercial gasoline. Further abatement of CO under 1000 ppm was carried out in a preferential oxidation reactor in tandem with the fuel processor. Additionally, measures on improving the fuel processor performance were put forward.