Impact of Adaptation on Flex-Fuel Vehicle Emissions When Fueled with E40

Abstract

Nine flex-fuel vehicles meeting Tier 1, light duty vehicle-low emission vehicle (LDV-LEV), light duty truck 2-LEV (LDT2-LEV), and Tier 2 emission standards were tested over hot-start and cold-start three-phase LA92 cycles for nonmethane organic gases, ethanol, acetaldehyde, formaldehyde, acetone, nitrous oxide, nitrogen oxides (NO(x)), carbon monoxide (CO), and carbon dioxide (CO(2)), as well as fuel economy. Emissions were measured immediately after refueling with E40. The vehicles had previously been adapted to either E10 or E76. An overall comparison of emissions and fuel economy behavior of vehicles running on E40 showed results generally consistent with adaptation to the blend after the length of the three-phase hot-start LA92 test procedure (1735 s, 11 miles). However, the single LDT2-LEV vehicle, a Dodge Caravan, continued to exhibit statistically significant differences in emissions for most pollutants when tested on E40 depending on whether the vehicle had been previously adapted to E10 or E76. The results were consistent with an overestimate of the amount of ethanol in the fuel when E40 was added immediately after the use of E76. Increasing ethanol concentration in fuel led to reductions in fuel economy, NO(x), CO, CO(2), and acetone emissions as well as increases in emissions of ethanol, acetaldehyde, and formaldehyde.

Iridium‐Catalyzed Hydrogenation of Carboxylic Acid Esters

“…Additionally, biodiesel is an easy fuel shift, as it can be used pure or mixed with petroleum‐based diesel fuel,5–8 as both conventional petroleum‐based and FAME‐based biodiesels have similar physical properties, heating values, and cetane numbers 3. 9, 10 FAME‐based biodiesels are also biodegradable, less toxic, have low aromatic and sulfur contents, and result in lower overall carbon emissions than petroleum‐based diesels 11. 12 These factors make biodiesel an ecofriendly and renewable alternative to petroleum‐based fossil fuels.…”

Performance and Regulated/Unregulated Emission Evaluation of a Spark Ignition Engine Fueled with Acetone–Butanol–Ethanol and Gasoline Blends

“…In the case of butanol, acetaldehyde can also be formed through β-scission of aC 4 H 8 OH [52]. Previous studies have concluded that the addition of ethanol and butanol in fuel blends could cause higher acetaldehyde emissions [48,53,54]. Figure 5b presents the impact of the equivalence ratio on acetaldehyde emission for all test fuels.…”

Real-world fuel use and gaseous emission rates for flex fuel vehicles operated on E85 versus gasoline

“…Variability in emission rates when comparing vehicles of different manufacturers is because of differences in FFV engine control strategies (Yanowitz et al 2013). FFV engines have sensors to analyze the fuel mixture and adjust the fuel injection and timing.…”