In the Process of generating Nitrogen, Carbon Molecular Sieve (CMS) plays a very vital role. With the help of CMS only Nitrogen is produced. CMS takes up the oxygen, carbon dioxide and other impurities and release the pure nitrogen. PSA is one of the unique processes in which gases are separated with the help of pressure swing technology is called PSA. In this process when the bed is in desorption mode with the help of release pressure it is been regenerated and then to swing to adsorption mode.

1. Nitrogen gas Generation By PSA
Method using Carbon molecular Sieves
It is a technology used to separate some gas
species from a mixture of gases under pressure
according to the species' molecular characteristics
and affinity for an adsorbent material.
It operates at near-ambient temperatures and
differs significantly from cryogenic distillation
techniques of gas separation.
Specific adsorptive materials
(e.g., zeolites, activated carbon, molecular sieves,
etc.) are used as a trap, preferentially adsorbing
the target gas species at high pressure. The
process then swings to low pressure to desorb the
adsorbed material.

2. Nitrogen gas Generation By PSA Method using
Carbon molecular Sieves
• Pressure swing adsorption processes utilize the fact that under high
pressure, gases tend to be attracted to solid surfaces, or "adsorbed". The
higher the pressure, the more gas is adsorbed.
• When the pressure is reduced, the gas is released, or desorbed. PSA
processes can be used to separate gases in a mixture because different
gases tend to be attracted to different solid surfaces more or less
strongly.
• If a gas mixture such as air is passed under pressure through a vessel
containing an adsorbent bed of zeolite that attracts nitrogen more
strongly than oxygen, part or all of the nitrogen will stay in the bed, and
the gas exiting the vessel will be richer in oxygen than the mixture
entering. When the bed reaches the end of its capacity to adsorb
nitrogen, it can be regenerated by reducing the pressure, thus releasing
the adsorbed nitrogen. It is then ready for another cycle of producing
oxygen-enriched air.
• This is the process used in medical oxygen concentrators used
by emphysema patients and others requiring oxygen-enriched air for
breathing.
• Using two adsorbent vessels allows near-continuous production of the
target gas. It also permits so-called pressure equalization, where the gas
leaving the vessel being depressurized is used to partially pressurize the
second vessel. This results in significant energy savings.

3. Types OF PSA Technology
 1.Double Stage PSA
 2.Rapid PSA
 Double Stage PSA:(DS-PSA, sometimes
referred to as Dual Step PSA). With
this variation of PSA developed for
use in Laboratory Nitrogen Generators
generation of nitrogen gas is divided
into two steps: in the first step, the
compressed air is forced to pass
through a carbon molecular sieve to
produce nitrogen at a purity of
approximately 98%; in the second
step this nitrogen is forced to pass
into a second carbon molecular sieve
and the nitrogen gas reaches a final
purity up to 99.999%.

4.  Rapid PSA : Rapid pressure swing
adsorption or RPSA is frequently
used in portable oxygen
concentrators.
 It allows a significant reduction in
the size of the adsorbent bed
when high purity is not essential
and feed gas can be discarded. It
works by quickly cycling the
pressure while alternately
venting opposite ends of the
column at the same rate.
 This means that un adsorbed
gases progress along the column
much faster and are vented at
the distal end, while adsorbed
gases do not get the chance to
progress and are vented at
the proximal end.

5. Best quality adsorbent for PSA
Aside from their ability to discriminate between different gases, adsorbents
for PSA systems are usually very porous materials chosen because of their
large specific surface areas.
silica gel, activated alumina, resin and zeolite. Though the gas adsorbed on
these surfaces may consist of a layer only one or at most a few molecules
thick, surface areas of several hundred square meters per gram enable the
adsorption of a significant portion of the adsorbent's weight in gas.
In addition to their selectivity for different gases, zeolites and some types of
activated carbon called carbon molecular sieves may utilize their molecular
sieve characteristics to exclude some gas molecules from their structure
based on the size of the molecules, thereby restricting the ability of the larger
molecules to be adsorbed

6. PSA Applications.
• One of the primary applications of PSA is in the
removal of carbon dioxide(CO2) as the final step
in the large-scale commercial synthesis
of hydrogen (H2).
• use in oil refineries and in the production of
ammonia(NH3).
• PSA technology in the removal of hydrogen
sulfide (H2S) from hydrogen feed and recycle
streams of hydro treating and hydrocracking units
• separation of carbon dioxide from biogas to
increase the methane(CH4) ratio.

7. Thank You
For more information about our PSA Grade adsorbents
please contact us:
304-307, III Floor, Prayosha Complex,
Chhani Jakat Naka
Vadodara- 390024, Gujarat, India.
Tel : +91-265-2761041 / 2761042
Toll Free No. : 1800-233-2677
Website: molecularsievedesiccants.com