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INDUSTRIAL GASES
Industrial gases are a group of gases that are specifically
manufactured or refined for use in industrial processes or in
medicine
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(1) HYDROGEN
Hydrogen is the most abundant element in the universe
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Hydrogen forms explosive
mixtures with air in concentrations that range from 4 to 74%
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Industrial production of hydrogen gas is by Steam Reforming of
Natural Gas or Methane
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Steam Reforming of Methane (CH4) or Natural Gas
This method is also known as Bosch Process
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700-1100 °C

CH4 (g) + H2O (steam)

CO (g) + 3H2 (g)

This is an endothermic reaction that yields syn gas (synthesis gas)
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Syn
gas is used as intermediates in creating synthetic natural gas and
for producing methanol
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130 °C

CO (g) + H2O (steam)

CO2 (g) + H2 (g)

CO2 can be separated from H2 by using Pressure Swing Adsorption
Units that utilize activated carbon as the adsorbent
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This widely happens in
a series of membrane or diaphragm cells
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Hydrogen gas is collected at the cathode, chlorine gas at the anode
and aqueous sodium hydroxide is the by product
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Low voltage direct current is utilized in this
case
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Oxygen gas forms at the anode and hydrogen gas forms at the
cathode, as per the equation below
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Ammonia can further be used to make
fertilizers
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 Hydrogen gas is used to process common fossil fuel products,
upgrading them to purer forms
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 Chemical removal of sulphur from crude oil and natural gas
(hydrodesulfurization) in order to upgrade them and to reduce toxic
combustion by products, including and mainly sulphur dioxide
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An
example is hydrocracking, where hydrocarbon molecules of
petroleum are broken down into simpler ones, such as kerosene and
gasoline, by addition of hydrogen under high pressure and in the
presence of a catalyst
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 Hydrogen gas is used in the conversion of unsaturated fats and oils
to saturated fats and oils
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 As a rocket fuel
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In the
manufacture of methanol, carbon monoxide reacts with hydrogen at
450 °C in the presence of a catalyst (a mixture of zinc oxide and
chromium (III) oxide)
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 Hydrogen is used in the electronics industry as a flushing gas during
the manufacture of silicon chips
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09% by volume of the earth’s
atmosphere
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The widely used method of industrial production of nitrogen gas is
by Fractional Distillation of Liquid Air
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 The particle free air is then freed from carbon dioxide and water
vapour by cooling, and thereafter compressed
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 The liquid air obtained is finally separated into its major and minor
components by fractional distillation, where nitrogen gas distils off
as a vapour at a temperature of ̶ 196°C
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79°C) and oxygen gas (boiling point of ̶ 183°C)
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Uses of Nitrogen Gas
 Manufacture of ammonia and ammonium compounds
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 As a refrigerant since liquid nitrogen has a low boiling point
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 Manufacture of nitrides
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 Nitrogen gas is used in mercury thermometers that register high
temperatures
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Rancidity is the chemical decomposition of fats, oils and lipids
resulting in undesirable odours and flavours
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 Nitrogen gas is used in military aircraft fuel systems to reduce fire
hazards
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95% by volume of the earth’s
atmosphere
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Oxygen is the third most abundant element in the universe by
mass, after hydrogen and helium
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The other common
methods are Pressure Swing Adsorption Process and Electrolysis
of Water
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 The particle free air is then freed from carbon dioxide and water
vapour by cooling, and thereafter compressed
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 The liquid air obtained is finally separated into its various
components by fractional distillation, where nitrogen gas distils off
as a vapour leaving oxygen gas (whose boiling point is of ̶ 183°C)
as a liquid
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Pressure Swing Adsorption Process
 In this process, a high pressure stream of clean dry air is passed
through one bed of a pair of identical zeolite molecular sieves,
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which adsorb nitrogen gas and deliver a gas stream that is 90 to 95%
oxygen gas at the outlet
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Another
cycle of clean dry air is again passed through the zeolite sieves,
where nitrogen gas is adsorbed by the zeolites and oxygen gas is
obtained at the outlet
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Electrolysis of Water
 Oxygen gas can likewise be produced, on a lesser scale, by
electrolysis of water
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The Hofmann Voltameter is used as a small
scale electrolytic cell

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