Hydrogen Production and Hydrogen Storage Techniques

Hydrogen is a key fuel which is turning the view of the energy consumption towards clean fuels which do not harm the environment and do not release harmful gases to the atmosphere as it produces water and an enormous amount of energy during combustion than any of the fuel. It increases the economy and efficiency of the machines but availability and production technologies are not yet effectively published, vigorous research work is going on to make cheaper, safer production of hydrogen but it all depends on the source and raw material required from which hydrogen can be produced.
Well let say the idea of fossil fuel containing high concentration of hydrogen but it make a circle to the starting step of pollution, so the only raw material which is abundant is water this can be used to produce hydrogen but why this is not used for production of hydrogen, split hydrogen mean again it requires energy.

Hydrogen production techniques:

1. By a method of silicon chip-based microreactor by methanol reforming.
2. Water splitting by a solar energy using thermochemical cycle or water electrolysis
3. Photoelectrolysis
4. Reforming of natural gas
5. Gasification of coal and biomass
6. The photo-biological method with the high-temperature decompositions.
7. Hydrocarbon reforming
8. Ammonia cracking
9. Pyrolysis
10. Aqueous reforming
11. High-temperature electrolysis
12. Photo-electrolysis (photolysis)
13. Photo-biological production (biophotolysis)

All above technologies depend on the raw material used for the production of hydrogen, the mostly known feedstocks and process dependents are Algae, Gas, Oil, Wood, Coal, biomass and Power.

a) Hydrogen from NG

We have three chemical production processes
1. Steam reforming
      CH + H O + heat CO + 3H
      CO + H2O CO2 + H2 + heat
2. Partial oxidation
      CH4 + 1 / 2O2 CO + 2H2 + heat
3. Auto thermal reforming the above two methods are used simultaneously.

b) Hydrogen from Coal

By coal gasification in a fixed bed or fluidized bed gasifier hydrogen can be produced
       C(s) + H2O + heat CO + H2

c) Hydrogen production from water by splitting

       H2O + electricity H2 + 1 / 2O

d) Alkaline electrolysis cell

hydrogen production by alkaline electrolysis cell using KOH and water for the application of hydrogen fuel cell

Alkaline electrolysis

        Electrolyte: 4H2O 4H+ + 4OH–
        Cathode: 4 H+ + 4e–2H2
        Anode: 4OH– O2 + 2H2O + 4e–
        Sum: 2H2O O2 + 2H2

e) Polymer electrolyte membrane (PEM) electrolysis

        Anode: H2O 1 / 2O2 + 2 H+ + 2e–
        Cathode: 2H+ + 2e– H2

Photosynthesis: 2H2O 4H+ + 4e– + O2
Hydrogen Production: 4H+ + 4e– 2H2

f) High-temperature decomposition

Thermo-chemical water splitting
(850 °C):          H2SO4 SO2 + H2O + 1 / 2
120 °C):           I2 + SO2 + 2H2O H2SO4 +
(450 °C):         2HI I2 + H2
SUM:              H2O H2 + 1 / 2O2

Hydrogen storage in solid form:

  • Using microporous metal-organic materials
  • Carbon nanotubes and graphite nanofibers
  • Platinum and palladium nonporous films
  • Using boron nitride nanotubes

Hydrogen storage in liquid form:

  • Composite tanks
  • Glass microspheres
  • Cryogenic liquid hydrogen (LH2)
  • NaBH4 solutions:NaBH4 (l) + 2H2O (l) 4H2 (g) + NaBO2 (s) (ideal reaction)
  • Rechargeable organic liquids