Diploma Thesis Defense by Mr Christos Valiantzas

"Hydrogen production from steam reforming of propane over supported metal catalysts"

Thesis Title: Hydrogen production from steam reforming of propane over supported metal catalysts

Friday 5 October 2018, at:11:00, Venue: Hall Κ2. Α3

Examination Committee

  • Assistant Professor Paraskevi Panagiotopoulou (advisor)
  • Professor Ioannis Yentekakis
  • Assistant Professor Danae Venieri

Abstract:

Within the next decade, the complete replacement of conventional fossil fuels by hydrogen will be possible for the production of electricity. The incorporation of hydrogen as a fuel is very important due to the high efficiency of electricity production, which can be achieved by using H2, as well as because hydrogen technology is environmental friendly. The present study aims to develop and operate a high energetically effective and eco-friendly system for electricity production with intermediate H2 production via LPG steam reforming. Hydrogen will be then feed to a PEM fuel cell for electricity production. The objective of the present study is catalysts synthesis, characterization and evaluation for the production of H2 via the reaction of steam reforming of propane. Catalysts should be characterized by high activity and selectivity toward hydrogen production, as well as by high resistance to coke formationin order to avoid catalyst deactivation. Thus, in the present study the effect of the nature of the metallic phase (Ni, Rh, Ru) and the support (Al2O3, CeO2), the metal loading (0,5-5,0% wt.%) as well as the steam to carbon molar ratio (S/C= 1,23-3,27) on catalytic activity and selectivity has been investigated for the reaction of steam reforming of propane. Among metals investigated, optimum results were obtained for Rh/Al2O3 catalysts, which is able to achieve high propane conversions even at reaction temperatures as low as 600 oC. Both catalyst activity and selectivity can be improved with increasing Rh loading. Results showed that when Rh is supported on Al2O3 carrier exhibits better catalytic performance compared to that obtained when it is supported on CeO2, which may be related to the significantly higher specific surface area of Al2O3. Increasing the steam/carbon molar ratio from 1,23 to 3,27 in the gas stream results in enhancement of both propane conversion and hydrogen selectivity over 1% Rh/Al2O3 catalyst.