10.7.3 Glycerol .................................................................. 279
10.7.4 Ethylene Glycol ......................................................280
10.7.5 Methanol.................................................................280
10.7.6 Ethanol ................................................................... 281
10.8
Tri-Reforming in SCW ....................................................... 283
References ........................................................................................ 285
Chapter 11 Water Dissociation Technologies for Hydrogen............................... 295
11.1 Introduction......................................................................... 295
11.2 Electrolysis and Its Derivative Technologies ...................... 297
11.2.1 Alkaline Electrolysis .............................................. 298
11.2.2 HTE Process........................................................... 298
11.2.3 HPE Process ........................................................... 299
11.2.4 Photoelectrolysis.....................................................300
11.2.5 Photo-Aided Electrolysis........................................300
11.2.6 Photovoltaic Electrolysis ........................................ 301
11.2.7 Solar Electrolysis.................................................... 301
11.3 Photochemical and Its Derivative Technologies ................. 301
11.3.1 Water Splitting on Semiconductor Catalysts
(Photocatalysis) ......................................................302
11.3.1.1 Titanium Oxide Photocatalysts .............302
11.3.1.2 Tantalates and Niobates ........................ 303
11.3.1.3 Transition-Metal Oxides, Nitrides,
and Oxynitrides..................................... 303
11.3.1.4 Metal Sulfides .......................................304
11.3.2 Photobiological Production of Hydrogen from
Water ......................................................................304
11.3.3 Plasma-Induced Photolysis..................................... 305
11.4 Thermal and Thermochemical Decomposition of Water ... 305
11.4.1 Thermochemical Decomposition of Water ............307
11.4.1.1 The UT-3 Cycle .....................................308
11.4.1.2 Zn/ZnO Cycle ....................................... 310
11.4.1.3 SnO/SnO 2 Cycle .................................... 311
11.4.1.4 Mixed Iron Oxide Cycle ....................... 311
11.4.1.5 Carbothermal Reduction of
Metal Oxides....................................... 312
11.4.1.6 Sulfur Family Thermochemical
Water Splitting Cycles........................... 312
11.4.1.7 S-I Cycle................................................ 314
11.4.1.8 The Westinghouse Process.................... 315
11.4.1.9 Copper–Chlorine Cycle ........................ 315
11.4.1.10 Copper–Sulfate Cycle ........................... 316
11.5
Other Miscellaneous Technologies ..................................... 319
11.5.1 Chemical Methods ................................................. 319
11.5.2 Magmalysis ............................................................ 320
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Contents