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ABSTRACT Environmental agencies are currently in the process of implementing a new air management program, which includes the improvement of fuel quality. In this work, exhaust emissions data and estimated [...]

The scope of the work carried out is aimed to evaluate the effects of blending methanol in the gasoline pool, particularly octane number and Reid vapor pressure increase when methanol is substituting methyl-tertiary-butyl ether in the formulation of Regular and Premium base gasolines. Isopropyl alcohol and ethanol have been investigated and found to be a promising co-blending alcohol to be mixed in gasoline methanol blends. Isopropyl alcohol is most effective below 3 vol%. Ethanol has been found to be the most promising co-blending alcohol able to reduce the Reid vapor pressure increase by 1.4 psi even with concentrations in the range of 2 vol%. The addition of isopropyl alcohol to the methanol–gasoline blends has shown the ability of a ternary mixture to further reduce the Reid vapor pressure of the finished gasoline and, subject to availability and price of isopropyl alcohol, could be of interest in further formulation studies focused on maximizing the saving on finished gasoline cost by reducing the Reid vapor pressure of base gasoline and/or increasing the methanol content. [ABSTRACT FROM AUTHOR]

In this work, we report a methodology to provide emission factors based on micro-reactor studies. We propose emission factors for ammonia (NH3, 158 mg/km), nitrous oxide (N2O, 322 mg/km) and molecular hydrogen (H2, 72 mg/km) for vehicles equipped with three-way catalytic converter (TWC). Our experimental conditions were similar to those prevailing on vehicles during catalyst light-off and transient urban driving cycle. NH3 and H2 emission factors reported in this work are quantitatively similar to those reported from vehicles. However, for N2O our results are almost 6 times higher than the average reported from vehicles during catalyst light-off. It is possible that the emission factor of N2O from light-duty vehicles reported during catalyst light-off is underestimated because the time (8.4 min) for recollecting the N2O emission contained in the exhaust gases is largest than the time (4 min) required to produce the main emission of N2O on the three way catalyst. The methodology represents one of the first attempts to predict emission factors from a micro-reactor. Besides, our proposal has the advantage that the main parameters involved in the formation of NH3, N2O and H2 can be controlled. Our method also complements the experimental strategies to estimate emissions, which are difficult to observe during the measurements of these compounds on vehicles. [ABSTRACT FROM AUTHOR]