Hydrogen is produced by this method due to increase the octane number of gasoline in the process of dehydrogenation of hydrocarbons.
C6H12 -> C6H6 + 3H2 C6H14 -> C6H6 + 4H2
Partial oxidation (POX) of hydrocarbons, Coal gasification (IGCC)
CH4 + 1/2 O2 = 2H2 + CO (1250 degC)
Methanol dissociation
CH3OH + H2O = 3H2 + CO2 (300 degC)
Ammonia Dissociation
2 NH3 = 3 H2 + N2 (300 degC)
Direct contact pyrolysis (DCP)
- direct conversion CH4 -> C + 2H2- no water, no oxygen used => NO greenhouse gases emissions- CH4 is bubbled through molten metal (Pb or alloys). Solid carbon is separeted by different metal and carbon density. Carbon "waste" could be used for carbon composites fabrication.- heat source: nuclear reactors (higher conversion efficiency), solar or CH4,H2 combustionnuclear DCP: http://www.cmt.anl.gov/science-technology/basicsci/hydrogen.shtml
Electrolytic decomposition of water
This method use the electricity to split water into hydrogen and oxygen.
2H2O + 2e -> H2 + 2OH (on the cathode)2OH - >H2O + 1/2 O2 + 2e (on the anode)H2O + electricity -> H2 + 1/2 O2 (globally) To gain hydrogen by means of this method we have to provide more energy in form of electricity (4.3 to 5.7 kWh/m3) than we are able to achieve from combustion of hydrogen (3 kWh/m 3 ). There are some proposals of using other sources of energy like nuclear energy or the energy of sun and wind to perform electrolysis but also these opportunities faces some problems.
Ad. An improved electrolysis technology:
* The Hot Elly method, based on hot electrolysis of water vapour at the temperature 900 degC. There is used solid electrolyte (ceramics) ZrO2 there. Efficiency ~85per cent.
C6H12 -> C6H6 + 3H2 C6H14 -> C6H6 + 4H2
Partial oxidation (POX) of hydrocarbons, Coal gasification (IGCC)
CH4 + 1/2 O2 = 2H2 + CO (1250 degC)
Methanol dissociation
CH3OH + H2O = 3H2 + CO2 (300 degC)
Ammonia Dissociation
2 NH3 = 3 H2 + N2 (300 degC)
Direct contact pyrolysis (DCP)
- direct conversion CH4 -> C + 2H2- no water, no oxygen used => NO greenhouse gases emissions- CH4 is bubbled through molten metal (Pb or alloys). Solid carbon is separeted by different metal and carbon density. Carbon "waste" could be used for carbon composites fabrication.- heat source: nuclear reactors (higher conversion efficiency), solar or CH4,H2 combustionnuclear DCP: http://www.cmt.anl.gov/science-technology/basicsci/hydrogen.shtml
Electrolytic decomposition of water
This method use the electricity to split water into hydrogen and oxygen.
2H2O + 2e -> H2 + 2OH (on the cathode)2OH - >H2O + 1/2 O2 + 2e (on the anode)H2O + electricity -> H2 + 1/2 O2 (globally) To gain hydrogen by means of this method we have to provide more energy in form of electricity (4.3 to 5.7 kWh/m3) than we are able to achieve from combustion of hydrogen (3 kWh/m 3 ). There are some proposals of using other sources of energy like nuclear energy or the energy of sun and wind to perform electrolysis but also these opportunities faces some problems.
Ad. An improved electrolysis technology:
* The Hot Elly method, based on hot electrolysis of water vapour at the temperature 900 degC. There is used solid electrolyte (ceramics) ZrO2 there. Efficiency ~85per cent.
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