Process for the desulfurization of flue gas

Patent · Tue Jan 04 04:00:00 EST 1977

OSTI ID:7117122

Longo, J M

A process for the removal of sulfur oxides from gases is described that is comprised of the steps of contacting the gas with a cerium oxide sorbent at conditions whereby the sulfur oxides present in the gas are sorbed by the cerium oxide sorbent and regenerate the cerium oxide sorbent by contacting it with a reducing atmosphere at conditions whereby the sorbent is substantially converted to a sulfur-free state. The gas may be an exhaust gas, e.g., from an automobile or a flue gas. This invention is especially preferred for treating flue gas. In this preferred embodiment, the flue gas may be contacted with the cerium oxide sorbent at a temperature of from 300/sup 0/ to 800/sup 0/C, to form cerium sulfate and/or sulfite and the sorbent is regenerated by contacting with a reducing gas, for example, hydrogen in admixture with steam or other inert gases at a temperature of from 500/sup 0/ to 800/sup 0/C to convert the cerium sulfate or sulfite to cerium oxide. During the regeneration step, the desorbed species is initially sulfur dioxide. However, when about 50% of the sulfur is removed from the sorbent, the desorbed species becomes H/sub 2/S. Thus, the instant invention provides SO/sub 2/ and H/sub 2/S in admixture with the excess reducing gas, which can be fed conveniently to the Claus plant for conversion into elemental sulfur.

• Assignee: Exxon Research and Engineering Co.
• Patent Number(s): US 4001375
• OSTI ID: 7117122
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200202* -- Fossil-Fueled Power Plants-- Waste Management-- Noxious Gas & Particulate Emissions
33 ADVANCED PROPULSION SYSTEMS
330703 -- Emission Control-- Sulfur Dioxide
AUTOMOBILES
CERIUM COMPOUNDS
CERIUM OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
DESULFURIZATION
ELEMENTS
EXHAUST GASES
FLUE GAS
FOSSIL-FUEL POWER PLANTS
GASEOUS WASTES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
POWER PLANTS
RARE EARTH COMPOUNDS
RECOVERY
REMOVAL
SULFUR
SULFUR COMPOUNDS
SULFUR OXIDES
THERMAL POWER PLANTS
VEHICLES
WASTES