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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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 2H2O (l)

2H2 (g) + O2 (g)

Applications of Oxygen Gas
 Oxygen gas is extensively used in medicine
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 Oxygen therapy is used in the treatment of pneumonia, for some
heart disorders and for patients with breathing difficulties
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 Oxygen gas is usually supplied to the lungs in order to displace
carbon monoxide, in cases of carbon monoxide poisoning
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 Liquid oxygen is used as a refrigerant because of its low boiling
point
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 Oxygen gas is used for emergency supply in commercial airplanes
in cases of cabin depressurization
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This process
utilizes some of the commercially produced oxygen gas
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The
oxyacetylene flame is widely used for these two processes
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 Oxygen gas is used in the treatment of wastewater
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(4) HELIUM
Helium is a colourless, odourless, inert and non-toxic monoatomic
gas
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Industrial production of helium is by Fractional Distillation of
Natural Gas
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Fractional Distillation of Natural Gas
 Natural gas contains up to 10% helium content
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A content of 0
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 Fractional distillation of natural gas is a cost effective and widely
used method of industrial production of helium
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The content of
helium in this crude gas is 75 to 80%
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 Activated charcoal further purifies helium gas to 99
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Applications of Helium Gas
 Liquid helium is used for cooling of superconducting magnets in
medical MRI (Magnetic Resonance Imaging) scanners
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 As a carrier gas in Gas Chromatography because of its inertness
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 As a shielding gas in arc welding processes
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 As laser pointers (helium-neon lasers)
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 Helium is used to estimate the age of rocks and minerals (using
helium dating)
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It is the third most abundant gas in the earth’s atmosphere
(0
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Industrial production of argon 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 argon gas distils off as
a vapour at a temperature of ̶ 186°C
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 Argon is used in graphite electric furnaces in order to prevent
graphite from burning
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 As a carrier gas in gas chromatography because of its inertness
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 Argon is used to provide an inert atmosphere during the processing
of titanium metal from its ore
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 Argon is used to provide an inert atmosphere in gas filled electric
bulbs
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 As a propellant for aerosol sprays
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 Argon is used for extinguishing fires, where valuable equipment
may be damaged by water or form
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The fire
gets extinguished when the oxygen levels fall below the limit that is
required for combustion

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