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In an effort to reduce ambient ozone and carbon monoxide levels, the U.S. Environmental Protection Agency has mandated the use of oxygenated fuels under the Clean Air Act. These fuels may contain varying amounts of methanol, ethanol, or other alcohols, and ethers. The current reference method for the analysis of methanol in vehicle emissions involves sample collection with impingers that contain water and the subsequent analysis of this aqueous solution by gas chromatography/flame ionization detection (GG/FID). The impinger method is problematical in that it is both time consuming and inconvenient in a test facility in which it is the only “wet” chemical method employed. In response to this problem, two alternative “non-wet” methanol methods were evaluated against the impinger method and against each other. The first alternative method employed a switched two-column GC/FID analysis of gaseous samples.

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.

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.