Introduction 1
The aim of experimental work 1
Chapter 1
1.1 Environmental situation 7
1.1.1 Greenhouse Effect 7
1.2 Potential Supplies for Future Energy 10
1.2.1 Renewable energy growth 10
1.2.2 Research in energy field:
General aspects and potentialities of the Fuel Cells 11 1.3 Conventional Hydrogen production costs and technologies 14
1.4 Additional applications of the Hydrogen 17
1.5 Hydrogen Delivery 18
Chapter 2
2.1 Thermal Processes for H2 production 19
2.1.1 Conventional Methane Steam Reforming process 19 2.1.1.1 Catalysts for Methane steam reforming reaction 24 2.1.1.2 Main deactivation mechanisms of catalyst 25
2.1.1.2.a Catalyst Sintering 26
2.1.1.2.b Coke formation 27
Chapter 3
3.1 A novel technology for Hydrogen Production: Membrane systems 29
3.1.1 Inorganic Membranes 30
3.1.1.1 Transport in palladium-based membranes.
Theoretical aspects 30
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3.1.2 Basic configurations of Membrane Reactors 34
3.1.2.1 Technological problems in MRs 34
3.1.2.2 Pd-based Membrane Reactors. State-of-the-art 35 3.1.2.3 Coke formation effect on MR performance 41
Chapter 4
4.1 Experimental details 44
4.1.1 Laboratory bench-scale experimental plant 44
4.1.2 Braze-welding process 49
4.1.3 Activation procedure of Ni-based catalyst used in MSR 50
4.1.4 Theoretical model for WGSR-based MR 52
Chapter 5
5.1 Results and Discussion 56
5.1.1 Membrane reactors for hydrogen production 56 5.1.1.1 Characterization and permeation experimental tests 56
5.1.1.2 Membrane Reactor MR1 59
5.1.1.3 Membrane Reactor MR2 66
5.1.1.4 Effect of Ls/Am ratio on MR performance 68
5.1.1.5 Membrane Reactor MR3 70
5.1.1.6 Membrane Reactor MR4. Effect of the catalyst distribution 72
5.1.1.6a Coke deposition effect 78
5.1.1.7 Sensitivity analysis in a Pd-based MR with WGSR 89 5.1.1.7a Influence of total feed pressure 89
5.1.1.7b Effect of sweep gas 94
5.1.1.7b.1 Inlet temperature 94
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5.1.1.7c Effect of the catalyst mass distribution 99
