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The gaseous and particulate emissions from a light-duty diesel powered passenger car were measured by a variety of chemical analysis techniques for three different fuels, typical No. 1 and No. 2 commercial diesel fuels and the Federal Register No. 2-D smoke test fuel. Hydrocarbon emissions were found to be inversely related to fuel molecular weight. The NO2/NO ratio was found to be much higher than for gasoline engines approaching 0.3 at low load. Particulate emissions were approximately 0.3 grams/mile for all fuels and driving cycles tested. Sulfate emissions were high, approaching that of some catalyst cars. Sulfate emissions decreased with decreasing fuel sulfur and increased by a factor of two in highway driving over urban driving. The potential pollution problems with such cars are worthy of further study.

Exhaust emissions from two diesel passenger cars were measured as a function of ambient temperature (43 - 82°F) over the urban dynamometer driving schedule of the Federal Test Procedure (FTP). Low ambient temperature did not affect rates of emission of total hydrocarbons, carbon monoxide, or nitrogen oxides. Fuel economy decreased with decreasing test temperature. Total particulate matter increased with decreasing test temperature, as did particulate organic emission rates (due primarily to adsorption of uncombusted diesel fuel). Polynuclear aromatic hydrocarbon emissions (ug/mile) and mutagenicity in the Ames Salmonella bioassay (rev/mile) were not affected by decreasing test temperature.

This paper reports the results of an exhaust emissions characterization from the non-catalyst control systems employed on the Mazda RX-4 rotary, the Honda CVCC, and the Chrysler electronic lean burn. Throughout the paper, exhaust emissions from these vehicles are compared to those from a Chrysler equipped with an oxidation catalyst and an air pump. The emissions characterized are carbon monoxide, hydrocarbons, nitrogen oxides, sulfur dioxide, sulfates, hydrogen sulfide, carbonyl sulfide, hydrogen cyanide, aldehydes, particulate matter, and detailed hydrocarbons. A brief description of the sampling and analysis procedures used is included within the discussion.

An experimental program was conducted to characterize the gaseous and particulate emissions from a 1975 Peugeot 504D light duty diesel-powered vehicle. The vehicle was tested over the 1975 Federal Test Procedure, Highway Fuel Economy Test, and Sulfate Emissions Test driving cycles using four different fuels covering a fair range of composition, density, and sulfur content. In addition to fuel economy and regulated gaseous emission measurements of hydrocarbons, carbon monoxide, and oxides of nitrogen, emission measurements were also obtained for non-regulated pollutants including sulfur dioxide, sulfates, aldehydes, benzo[a]pyrene, carbonyl sulfide, hydrogen cyanide, nonreactive hydrocarbons, and particulate matter. The results are discussed in terms of emission trends due to either fuel type or driving cycle influence.

The activity and durability of a platinum-rhodium automotive three-way catalyst were investigated as a function of lead and manganese fuel levels using a pulse-flame combustor. Total hydrocarbons, carbon monoxide, and nitric oxide conversions and three-way (HC/CO/NO) conversion efficiency windows were determined for approximately 24,000 combustor-simulated miles. The window for 80% HC/CO/NO efficiency disappeared at approximately 9,000 miles, 13,500 miles, and 4,500 miles for 0.5 g of lead per gallon of fuel, 0.0625 g of manganese per gallon of fuel, and a combined manganese and lead misfueling study, respectively. The catalyst's nitric oxide reduction activity displayed the greatest sensitivity to catalytic poisoning with both lead and manganese fuels.

Refueling emissions from a 1986 Pontiac Grand Am were characterized using 3 test fuels, including a winter, summer and intermediate blend gasoline under a variety of seasonal temperature conditions. The effects of varying fuel volatility (10.1 to 13.3 psi RVP), dispensed fuel temperature (50 to 88°F), and vehicle tank fuel temperature (40 to 108°F), were investigated. Hydrocarbon (HC) emissions ranged from 2.90 to 7.41 grams per gallon of delivered fuel. Detailed hydrocarbon analyses were completed for both the test fuels (dispensed fuel and tank fuel) and the refueling emissions. The average (all test fuels and temperature scenarios) test gasoline composition was 46.1% paraffins, 6.3% olefins, 45.2% aromatics, with an average carbon number of 7.42; the average HC emission rate was 4.69 g/gal; and the average emissions composition was 81.4% paraffins, 12.2% olefins, 5.4% aromatics, with an average carbon number of 4.79.

Gaseous and particulate emission rates from seven class 2B, one class 5 and six class 6 heavy-duty gasoline- and diesel-powered trucks were determined using transient chassis dynamometer test procedures. All vehicles were tested at approximately 70% of their rated gross vehicle weight over the Heavy-Duty Transient Cycle and the Durham Road Route driving cycles. The sensitivity of emission rates to vehicle configuration, engine design, and driving cycle characteristics was examined. Emissions characterization included total hydrocarbons, carbon monoxide, oxides of nitrogen, fuel economy, total particulate matter, CH2Cl2 %-extractables, particulate organics, inert material, particle size less than 2μ, and lead, bromine, and chlorine analyses. For a particular type of engine (gasoline or diesel), class 2B truck emission rates were less than class 5 or 6 truck emission rates.

This paper describes the results of a study to examine the effects of various experimental variables on the quantity and composition of emissions associated with motor vehicle refueling. Problems related to accurate laboratory simulation of vehicle refueling are discussed. Preliminary results include emission rates for total hydrocarbons, benzene and 82 other hydrocarbon compounds for a single test vehicle under a variety of temperature and test conditions.