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A low thermal mass, metal monolith, catalytic converter, was tested for reducing automotive emissions for applications both as lightoff and main converters. FTP testing was carried out to measure the first four minutes of Bag 1 emissions from a 2.2l, fuel-injected Plymouth Reliant, at New York State, Automotive Emissions Laboratory, Albany (NY-AEL). The car had aproximately 17,000 miles when tested and its driving history had been catalogued by NY-AEL. Both resistively heated and non-resistive mini-converter systems were tested in series with a conventional replacement new automotive converter. The non-resistive converter reduced HC, CO and NOx emissions by more than 50%, 40% and 30%, respectively. despite excess air addition. Lightoff occurred within 10 seconds of engine start. A modified cycle exploring steady state conditions under load showed greater than 70% reduction in NOx.

Particulate emissions data are presented from a group of 19 in-use diesel automobiles. Five driving cycles and three fuel/lubricating oil combinations have been used to obtain particulate emissions data and also to collect particulate samples for chemical and bioassay characterization studies. Particulate samples were solvent extracted with dichloromethane to obtain the soluble organic fraction (SOF) of the emitted particulate. Particulate and SOF data are presented for emission/distance, emission/time and emission/fuel consumed basis by vehicle manufacture, driving cycle, and fuel/oil subcategory. Some SOF samples have been used in the bioassay test of Ames, and these results are presented for different vehicles and driving cycles. Particulate emissions, SOF emissions and bioassay activity results are presented in terms of mileage accumulation effects.

A sample of 20 in-use light-duty diesel vehicles were extensively and repeatedly tested for two years. Gaseous and particulate emissions were measured for the FTP, HFET, CFDS, NYCC, 50 mph cruise, and idle driving cycles. Vehicles were tested with both as-received and control fuel and lubricating oil. Particulate extracts were obtained by Soxhlet extraction with dichloromethane, and the extracts assayed for mutagenic activity by the Ames Salmonella typhimurium/microsome method with TA98(-) tester strain. Particulate, extract, residue, hydrocarbons, carbon monoxide, nitrogen oxides, % extractible, fuel economy and Ames activity are discussed as they relate to driving cycles and mileage accumulation. Driving cycles were found to affect emissions more strongly and consistently than does mileage accumulation. Cycle and mileage effects were observed in some cases for Ames activity but were not well defined.

As a response to experiences of in-service plugging of police vehicles, the Automotive Emissions Laboratory has examined 20 high-mileage cars from the New York State Thruway Authority, whose total fleet numbers approximately 100 vehicles. Fourteen catalysts from twelve vehicles were found to be at least 25 percent physically plugged with thin deposits distributed on the front surface of the forward monolith. Analysis of these catalyst deposits by X-Ray Fluorescence indicated that the plugging material was composed mainly of oil additive components (zinc, calcium, barium, phosphorous) as well as iron and lead. Except for one converter with a deposit assay of 25 weight percent manganese, these deposits were in the range of 0.2 to 9.2 weight percent manganese. Our results indicate that monolith catalysts can plug in the absence of significant levels of manganese.