{{Short description|Removal of sulfur from a substance}} {{See also|Raney nickel#Applications in organic synthesis}}
'''Desulfurization''' or '''desulphurisation''' is a chemical process for the removal of sulfur from a material.<ref>{{cite web |title=Desulfurization |url=https://goldbook.iupac.org/terms/view/D01622 |publisher=International Union of Pure and Applied Chemistry}}</ref> The term usually refers to the removal of sulfur from a molecule or a material by hydrogenolysis:<ref>{{cite journal|last1=Babich|first1=I|title=Science and technology of novel processes for deep desulfurization of oil refinery streams: a review |journal=Fuel|date=April 2003|volume=82|issue=6|pages=607–631|doi=10.1016/S0016-2361(02)00324-1|bibcode=2003Fuel...82..607B}}</ref> :{{chem2|R2S + 2 H2 -> 2RH + H2S}} Hydrogen is the ultimate sulfur acceptor. As applied to oil refinery streams, the conversion is known as hydrodesulfurization. These processes are of industrial and environmental importance as they provide the bulk of sulfur used in industry (Claus process and Contact process), 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.
A laboratory scale hydrogenolysis is the desulfurization of thioketals by Raney nickel. In such cases, the hydrogen is contained within the reagent. [[File:Desulfurization of thioacetal using Raney Ni (cropped).svg|alt=Chemical reaction: Thioacetal breaks into ethane, nickel sulfide and a hydrocarbon under the action of hydrogen and Raney nickel.|class=skin-invert-image|center|thumb|475x475px|Example of desulfurization of thioacetals using Raney nickel]] ==Desulfurization without hydrogenolysis== Desulfurization without hydrogenolysis is uncommon. Some trithiocarbonates can be coupled by desulfurization with phosphites or phosphines as S-atom acceptors. This approach has been described by the following equation:<ref>{{cite journal |doi=10.1021/cr0306440 |title=Synthesis Strategies and Chemistry of Nonsymmetrically Substituted Tetrachalcogenafulvalenes |date=2004 |last1=Fabre |first1=J. M. |journal=Chemical Reviews |volume=104 |issue=11 |pages=5133–5150 }}</ref> :{{chem2|2 R2C\dS + 2 PR'3 -> R2C\dCR2 + 2 R'3P\dS}}
==Other== Other processes used for desulfurization include hydrodesulfurization, the SNOX process and the wet sulfuric acid process (WSA process).
== See also == * Shell–Paques process * Flue-gas desulfurization * Biodesulfurization
== References == {{Reflist}}
{{Authority control}} Category:Desulfurization {{chem-process-stub}}