J. Polanski, P. Bartczak, R. Sitko, T. Siudyga, A. Mianowski, J. Szade, J. Lelatko
University of Silesia, Poland
pp. 67 - 70
Keywords: nanocatalysis, ammonia cracking, nano-Pd/Ni
Ammonia cracking is a method used in the treatment of flue gases from coal or biomass gasification or for hydrogen generation in chemical or related industries. It is an important issue in hydrogen economies. As a carbon-free compound, ammonia provides a potential source of ecological fuel for mobile and stationary power generation, especially for fuel cells, where CO impurities are unacceptable. However, more efficient catalysts are needed for new technologies in this area. Herein, we report a new nanometallic catalyst for ammonia cracking at temperatures well below 500°C. We have discovered that supporting Pd nanoparticles (Pd NPs) directly on Ni grains provides an active and durable catalyst for this reaction. We also report a new, facile and scalable wet chemical method for supporting Pd on Ni; in this method, Pd NPs initially supported on SiO2 were placed in contact with Ni grains to yield, after a final SiO2 digestion, a Pd/Ni unalloyed contact. The comparison of the novel PdNPs/Ni catalyst with these reported in the literature clearly indicates much better hydrogen productivity of the new system for which a TOF reaches a value of 10,571 molNH3/molMe(NP) h at 600°C under a flow of 12 dm3/h.