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It is frequently useful to calculate the theoretical composition of the major components of vehicle exhaust. A software program has been written in Basic (or Quick Basic) which allows the convenient calculation of volume percents of CO, CO2, O2, H2, and H2O from fuel composition (H/C and O/C ratios), the water content (dew point) of the combustion air, and a chosen stoichiometry (air/fuel ratio). The program considers the Water Gas Shift reaction and the production of hydrogen under fuel rich conditions. The program is valid for both standard gasolines and oxygenated blends. Vehicle emissions data, collected to compare values calculated by the program with actual experimentally determined values from vehicle exhaust, show good agreement for measurements made at a series of air/fuel ratios ranging from lambda of 0.85-1.2.

Particulate and manganese mass emissions have been measured as a function of mileage for four Escort and four Explorer vehicles using 1) MMT (Methylcyclopentadienyl Manganese Tricarbonyl) added to the gasoline at 1/32 g Mn/gal and 2) gasoline without MMT. The MMT was used in half of the fleet starting at 5,000 miles. The vehicles were driven on public roads at an average speed of 54 mph to accumulate mileage. This report describes the particulate and manganese emissions, plus emissions of four air toxics at 5,000, 20,000, 55,000, 85,000 and 105,000 miles. Four non-regulated emissions were measured and their average values for vehicles without MMT were 0.6 mg/mi for formaldehyde, 0.7 mg/mi for 1,3-butadiene, 9 mg/mi for benzene and 12 mg/mi for toluene. Corresponding values for MMT-fueled vehicles were between 1.5 and 2.4 times higher.

A liquid, while burning on a cold surface, can dissolve significant amounts of its combusion products. After reaction with a suitable solid surface, these products are identifiable by infrared spectroscopy. Corrosion derived in this manner can be quantified gravimetrically. Thus, steel corrosion from methanol combustion was measured by burning several layers of the alcohol on a steel coupon, while recording the coupon weight. Corrosion enhancement by fuel contaminants, such as sulfur or peroxide, was measured by this method, as well as, corrosion inhibition by cofuels and lubricant layers. The flaming coupon test is also suitable for comparing corrosion resistance of metals as a function of alloy composition, or for ranking protective coatings. Some of the corrosion fundamentals involved in the rust formation during this test are analyzed.

Burning methanol produces formic acid, which can cause steel corrosion at temperatures below the dew point of the exhaust gas. Because of the potential of methanol as an alternate automotive fuel, it is of interest to evaluate the conditions, which can aggravate or mitigate the extent of this rust formation. Rust formation is promoted by such methanol contaminants, as organic chloride and peroxide. The effects of these species on rust formation were measured quantitatively as a function of concentration by the application of burning methanol in a simple, novel coupon test. Rust formation can be inhibited by cofuels or by lubricants. Effects of Indolene Clear and of other methanol cofuels were measured by the coupon test as a function of concentration. Corrosion protection by engine oil was evaluated as a function of acid-neutralizer concentration and layer thickness.