There are three main commercial methods for hydrogen production: steam reformation, coal gasification, and thermal decomposition of hydrocarbons. Steam reformation involves reacting hydrocarbons like natural gas with steam at high temperatures over a catalyst to produce hydrogen and carbon oxides. The mixture is then shifted to increase hydrogen concentration before purification. Coal gasification uses superheated steam to gasify coal, producing water gas that is further reacted to hydrogen. Thermal decomposition produces hydrogen as a byproduct when cracking hydrocarbons at high heat.

1. G Mothy
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2. Production of Hydrogen
1.Commercial methods 2.Laboratory methods 3.Solar Energy
Steam
Reformation
Coal and
Steam
Thermal decomposition of
hydrocarbon
Electrolysis
Chemical
Methods
Water splitting
Photolysis of water
using co-
ordination
catalysis

3. Steam Reformation
It is process of reacting steam with hydrocarbons in the presence of a
catalyst at high temperature to obtain hydrogen and carbon oxides.

4. Feed
Steam
reforming
8000CSteam
H2 and
CO
Higher H2%
+CO2
Steam
FeO catalyst
Shift reaction
Comprestion
and cooling
H2 gas
Liquid CO2
Feed=Sulphur free natural gas
CH4,naphtha,petroleum fraction.
Catalyst=Ni or FeO (reforming),FeO (for shift
reaction)
Temp=8000C(reforming)
3700C(Shift )
Pressure=Less than 1 atm.

5. Reactions:
CH4 +H2O CO +3 H2
In general ,
CnH2n+2 +nH2o n CO + (2n+1) H2
In shift reaction, more stream is mixed with
(CO+H2) mixture to get higher % H2 mixture.

6. Shift Reactions:
This reaction produces more hydrogen by passing
steam in the mixture of CO and H2 ,in the presence
of FeO catalyst at 3700C
CO +H2O CO2 + H2
Then the (CO2 +H2) mixture is compressed and
cooled to get liquid CO2 and H2 gas.
The Alternate Way to remove CO2 from mixture is
scrubbing the (CO2 +H2) mixture with alkali
solution or a solvent which can be recycled after
evaporating out CO2.

7. Coal & Steam Reaction:
Coal on heating with Superheated steam produces the water
gas (temperature about 7000cC) which is then reacted with
more steam to produce additional hydrogen by shift reaction.
C +H2O CO +H2 CO2 +2 H2
The H2 obtained in this process is less and it is associated wit
h impurity of H2S, SO2.
Hence this process is less preferred, although very cheap
method.
FeO catalyst
H2O, 3700C

8. Thermal Decomposition of temperature :
Hydrogen is a byproduct in the manufacture of carbon-black from thermal
Cracking of natural gas or hydrocarbons of a petroleum fraction at 800-9000C.
After removing other gaseous impurities by scrubbing, a relatively lesser purity
hydrogen is obtained.
CnH2n+2 n C +(2n+2) H2
Purification :
1.) Liquefaction process
2.)Diffusing H2 gas through thin and very
low porosity Palladium films at 3000C.