Maximizing conversion of nitrogen oxides in the treatment of combustion exhaust gases

Patent · Tue Apr 27 04:00:00 EDT 1976

OSTI ID:7185924

Meguerian, G H; Kaneko, Y

A three-catalyst process for maximizing the conversion of nitrogen oxides during the treatment of combustion exhaust gases is provided. This process consists of: (1) contacting the combustion exhaust gas in a zone with a nitrogen-oxide-reduction catalyst; (2) introducing a stream of secondary air into the gas; (3) contacting this air-gas mixture in a second zone with a catalyst for decreasing ammonia; (4) introducing a second stream of secondary air into the gas; and (5) contacting this air-gas mixture in a third zone with an oxidation catalyst for the oxidation of carbon monoxide and hydrocarbons. The first stream of secondary air provides about 3 to about 8 volume percent air, based on the volume of primary air being employed in the combustion, while the second stream of secondary air is sufficient, when added to the oxygen remaining in the gas containing decreased amounts of ammonia, to provide substantially complete oxidation of the carbon monoxide and hydrocarbons. This process may be employed to treat automobile exhaust gases.

• Assignee: Standard Oil Co.
• Patent Number(s): US 3953576
• OSTI ID: 7185924
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330701* -- Emission Control-- Nitrogen Oxides
330702 -- Emission Control-- Carbon Monoxide
330704 -- Emission Control-- Hydrocarbons
AIR
AUTOMOBILES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYTIC CONVERTERS
CHALCOGENIDES
CHEMICAL REACTIONS
EQUIPMENT
EXHAUST GASES
FLUIDS
GASEOUS WASTES
GASES
HYDROCARBONS
MIXING
NITROGEN COMPOUNDS
NITROGEN OXIDES
OPERATION
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
REDUCTION
VEHICLES
WASTES