(417e) Hydrogen Production from Thermo-Neutral Reforming of Diesel Using Dual Catalyst System

Hydrogen production is gaining increased importance globally for producing clean energy for using in fuel cells. Hydrogen demand in the refining sector is also expected to continue its growth driven mainly by stricter fuel specifications. In addition, hydrogen-based fuel cells for automotive and stationary applications are gaining popularity for various reasons including their higher efficiencies and lower emissions. Use of liquid hydrocarbon fuels to generate hydrogen is being considered as an immediate solution for large scale hydrogen production. Diesel steam reforming is known for posing a major challenge due to its high carbon content, aromatics, and sulfur, which play a major role in catalyst deactivation. Thermo-neutral reforming of diesel with single TNR catalyst had a limited conversion and lower subsequent hydrogen yield. To overcome this problem a dual catalyst system using a multi-components TNR catalyst and a commercial steam reforming catalyst was achieved with complete diesel conversion. A two stage catalyst loading was attempted using TNR catalyst at the top of the catalyst bed and steam reforming catalyst at the bottom of the bed. Relatively, smaller amount (6 cc) of TNR catalyst was loaded on top of larger amount (50 cc) of steam reforming catalyst. The catalyst was reduced with dilute hydrogen for 4 hours prior to the reforming operation. Initial assessment of the catalysts performance showed complete conversion of diesel for a period of 70 hours time-on-stream with above 60 mol% hydrogen yield. Above 20% water conversion was achieved resulting higher hydrogen yield (above 90 l/h). During the experiment higher steam to carbon ratio (3.5) was used to prevent coke formation. The results show promising features of diesel reforming for on-board as well as stationary power generation applications and detail results on catalyst formulation, characterization and testing with diesel fuel will be presented.