Desulfurization or desulphurisation is a chemical process for the removal of
sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formul ...
from a material. This involves either the removal of sulfur from a molecule (''e.g.'' A=S → A:) or the removal of sulfur compounds from a mixture such as oil refinery streams.
These processes are of great industrial and environmental importance as they provide the bulk of sulfur used in industry (
Claus process
The Claus process is the most significant gas desulfurizing process, recovering elemental sulfur from gaseous hydrogen sulfide. First patented in 1883 by the chemist Carl Friedrich Claus, the Claus process has become the industry standard.
Th ...
and
Contact process
The contact process is the current method of producing sulfuric acid in the high concentrations needed for industrial processes. Platinum was originally used as the catalyst for this reaction; however, as it is susceptible to reacting with arsenic ...
), sulfur-free compounds that could otherwise not be used in a great number of catalytic processes, and also reduce the release of harmful sulfur compounds into the environment, particularly
sulfur dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic a ...
(SO
2) which leads to
acid rain
Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists between 6.5 and 8.5, but ac ...
.
Processes used for desulfurization include
hydrodesulfurization
Hydrodesulfurization (HDS) is a catalytic chemical process widely used to remove sulfur (S) from natural gas and from refined petroleum products, such as gasoline or petrol, jet fuel, kerosene, diesel fuel, and fuel oils. The purpose of rem ...
,
SNOX process The SNOX process is a industrial process, process which removes sulfur dioxide, nitrogen oxides and particulates from flue gases. The sulfur is recovered as concentrated sulfuric acid and the nitrogen oxides are reduced to free nitrogen. The process ...
and the
wet sulfuric acid process
The wet sulfuric acid process (WSA process) is a gas desulfurization process. After Danish company Haldor Topsøe (company), Haldor Topsoe introduced this technology in 1987, it has been recognized as a process for recovering sulfur from various p ...
(WSA process).
See also
*
Shell–Paques process
The Shell–Paques process, also known by the trade name of Thiopaq O&G, is a gas desulfurization technology for the removal of hydrogen sulfide from natural-, refinery-, synthesis- and biogas. The process was initially named after the Shell Oil an ...
*
Flue-gas desulfurization
Flue-gas desulfurization (FGD) is a set of technologies used to remove sulfur dioxide () from exhaust flue gases of fossil-fuel power plants, and from the emissions of other sulfur oxide emitting processes such as waste incineration.
Methods
...
*
Biodesulfurization
Biodesulfurization is the process of removing sulfur from Petroleum, crude oil through the use of microorganisms or their enzymes.
Background
Crude oil contains sulfur in its composition, with the latter being the most abundant Chemical element ...
References
Chemical processes
Sulfur
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