Hydrogen is projected to be one of the primary energy carrier in the 21st century. Its combustion and oxidation is pollution free and supplies sufficient energy for transportation and other applications.

 

The polymer electrolyte fuel cell (PEMFC) is a potential candidate for direct electricity production from hydrogen. However infrastructures for refueling fuel cells with hydrogen which is the preferred fuel for powering fuel cells are not available today, therefore it is required to produce hydrogen using current fueling facilities.

 

One of the options for hydrogen production is converting hydrocarbon fuels such as natural gas, butane gas, gasoline, diesel or methanol into hydrogen via reforming processes. There are major three techniques for reforming fuels into hydrogen-rich synthetic gas-steam reforming(SR), partial oxidation(POX) and autothermal reforming(ATR).

 

• Steam reforming which is a traditional has been widely used in chemical plants because of output of high hydrogen content. However SR requires signigicant energy input due to the high endothermicity of SR reaction, which is the main disadvantage to develop smaller systems.

 

• Partial oxidation reforming with highly exothermic reaction does not require heat supply which leads to simple reactor desing appropriate for small system. But the hydrogen content in product is low and possibility of coking is high.

 

• Autothermal-type reformers combine SR and POX by feeding fuel, water and air into the system at the same time. ATR utilizes exothermic oxidation as a heat source for endothermic reforming reaction inside the reactor with reducing or removing the burden of heat exchange. ATR also shows more flexibility and controllability with dynamic load changes as well as a shorter start-up time compared to SR.