Effect of high temperatures on three-way automotive catalysts

Book · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5603689

Hammerie, R H; Wu, C L

The thermal deactivation of current automotive three-way catalysts (TWCs) was studied under various high temperature conditions to determine which were most damaging. The catalysts were aged on an engine dynamometer simulating the U.S. emission durability cycle with additional periodic exposure to high temperatures. The deactivation was measured as a function of the duration, temperature and air-fuel ratio during the high temperature exposure. With lean air-fuel ratios during the high temperature exposure, TWC performance as measured at 600/sup 0/F was most susceptible to deactivation showing appreciable loss of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) conversions after 20 minutes of aging at 1600/sup 0/F. The TWC performance as measured at 800/sup 0/F had comparable loss only after 60 minutes of aging at 2200/sup 0/F. With rich air-fuel ratios the TWC performance remained nearly unaffected by aging up to 2000/sup 0/F. The results are explained in terms of the loss of active metal surface area and the rates of the various reactions involved in TWC operation.

• OSTI ID: 5603689
• Report Number(s): SAE-TP-840850
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AGING
AIR POLLUTION MONITORING
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CATALYTIC CONVERTERS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
COMPARATIVE EVALUATIONS
DEACTIVATION
DYNAMOMETERS
ELEMENTS
EQUIPMENT
EXHAUST GASES
FLUIDS
FUEL-AIR RATIO
GASEOUS WASTES
GASES
HIGH TEMPERATURE
HYDROCARBONS
KINETICS
MEASURING INSTRUMENTS
METALS
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
REACTION KINETICS
SERVICE LIFE
SIMULATION
SURFACE AREA
SURFACE PROPERTIES
TEMPERATURE EFFECTS
VEHICLES
VERY HIGH TEMPERATURE
WASTES