(98j) Methanol Reforming on Structured Catalyst and Microchannel Reactors

Methanol is often considered the best choice of a liquid fuel to generate hydrogen due to its high energy density, low cost and easy transportation. In addition, the reaction of steam reforming of methanol does not require high temperature that results in an easy temperature control. The use of micro-reactors for hydrogen production gains an increasing importance from the point of view of creating a portable and low cost hydrogen source for numerous applications, in particular as feeding for fuel cell. Micro-reactors have the advantages of high surface-to-volume ratio, fast response time, ease integration, and small footprint, which are ideal for portable power systems. In addition, enhanced mass and heat transport properties are also recognized as advantages of micro-reactors.

Catalysts (CuZnAl2O3 or Pd/ZnO) were deposited on the micro-channel walls by the washcoating method. To optimize the coating procedure, preliminary studies were carried out by coating micro-monoliths (presenting the same channels size) of the same alloy, varying different parameters and properties: particle size, solid content, additives, and pH of the slurry. The coating procedure result was evaluated by means of the specific load (mg/cm²), homogeneity (SEM), adhesion (ultrasound test) and catalytic activity.

 The best results were obtained balancing several parameters like the solvent nature, the pH or the additives to improve specific load and adhesion without loosing catalyst activity. Micro-channels blocks showed excellent reforming activity with very low CO production (<1%)