Exhaust gas conversion process

Patent · Tue Aug 27 04:00:00 EDT 1974

OSTI ID:7332830

Hass, R H

A method for the catalytic conversion of nitrogen oxides, hydrocarbons, and carbon monoxide in the exhaust of internal combustion engines is described that overcomes prior art problems relating to first stage catalyst deactivation and eliminates the need for exhaust gas recycling. The exhaust gas is passed at a temperature of above 700 F through a contacting zone containing an oxidation-reduction catalyst that consists of at least one easily reducible oxide of a multivalent transitional metal. Air is injected into the flow path of the exhaust gas at several points in the contacting zone to establish a downstream zone where net oxidizing conditions prevail and an upstream reducing zone. The oxygen concentration of the exhaust gas is increased gradually in the downstream direction of the conversion zone in order to maintain a generally increasing O/sub 2//CO mole ratio in the initial section of the conversion zone. The O/sub 2//CO ratio in the initial section is less than stoichiometric, while the O/sub 2//CO ratio in latter part of the conversion zone is greater than stoichiometric.

• Assignee: Union Oil Co. of California
• Patent Number(s): US 3832443
• OSTI ID: 7332830
• 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
AIR POLLUTION CONTROL
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYTIC CONVERTERS
CHALCOGENIDES
DESIGN
ENGINES
EQUIPMENT
EXHAUST GASES
FLUIDS
GASEOUS WASTES
GASES
HYDROCARBONS
INTERNAL COMBUSTION ENGINES
MIXING
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
WASTES