Experimental and Kinetic Modeling Study of 3-Methyl-2-butenol (Prenol) Oxidation

Abstract

Longer chain alcohols with 4–5 carbon atoms are attractive alternative fuels as they can be derived from biological sources and since their combustion leads to lower exhaust gas levels of NO x and soot compared to commercial fossil fuels. The auto-ignition behavior of fuels that contain both a hydroxyl group and a CC double bond in their molecular structure is not well established in the literature. Understanding the influence of these functional groups on the ignition behavior of fuels is critical in the development of tailor-made fuels for advanced combustion engines. In this study, ignition delay times of an unsaturated alcohol, 3-methyl-2-butenol (prenol), are measured using a high-pressure shock tube and a rapid compression machine at pressures of 15 and 30 bar at equivalence ratios of 0.5, 1.0, and 2.0 in “air” in the temperature range 600–1400 K. A detailed kinetic model is developed and validated using the new experimental data in this study. In addition, speciation data in a jet-stirred reactor, ignition delay times, and laminar burning velocities available in the literature were also used to validate the new kinetic model. Fuel flux and sensitivity analyses are performed using this new model to determine the important fuel consumption pathways and critical reactions that affect the reactivity of prenol.

Virtual Special Issue of Recent Advances in Fundamentals of Biomass and Biofuel Combustion

“…Specifically, they compared how laminar flame speeds and ignition delay times vary with the content of both alcohols. Lokachari et al reported results from ignition and combustion experiments with an unsaturated alcohol species, 3-methyl-2-butenol (prenol), performed in a shock tube and a rapid compression machine. They obtained ignition delay times as well as a new detailed kinetic model for the oxidation of this alcohol.…”

“…Specifically, they compared how laminar flame speeds and ignition delay times vary with the content of both alcohols. Lokachari et al 14 16 The last paper in this group described spray vaporization characteristics of alcohols and esters. Specifically, Singh et al 17 investigated acetone, ethanol, and biodiesel spray flames to link the spray characteristics and flame stability.…”

The effect of hydrogen bonding on the reactivity of OH radicals with prenol and isoprenol: a shock tube and multi-structural torsional variational transition state theory study

“…Therefore, one can expect that OH initiated oxidation of isoprenol and prenol exhibits a large reactivity difference as compared to alkenes + OH reactions, and hence, the strategy of estimating the rate coefficients by using reaction analogy can introduce large uncertainty. Lokachari et al 26 also investigated the oxidation of prenol by developing a chemical kinetic model that was validated against JSR and flame speed data from literature, as well as HPST and RCM ignition delay time data measured in their study at j = 1 and 2, in the temperature range of 600-1400 K and at pressures of 15 and 30 bar. Their model showed a suppressed auto-ignition behavior which they attributed to the unique structure of prenol which contains a branch, a double bond and an alcohol functional group.…”

“…Additionally, the OH addition to the double bond of prenol and the subsequent O 2 addition highly affected the prenol auto-ignition characteristics as the subsequently formed RO 2 and QOOH radicals terminated via either Waddington pathway or the formation of aldehyde + HO 2 instead of undergoing a complete low temperature chemistry (chain branching). Lokachari et al 26 model was further utilized by Fioroni et al . 27 to study the RON predictions of prenol blend with four components surrogates (iso-octane, toluene, n -heptane and 1-hexene); nevertheless, the model failed to capture the synergetic effect observed experimentally and further model refinements were recommended.…”

Prenol as a Next-Generation Biofuel or Additive: A Comprehension of the Hydrogen Abstraction Reactions by a H Atom

“…11 Quantum chemical calculations at the CBS-QB3 level of theory were employed to determine thermal rate constants for several reactions. More recently, a detailed experimental study of the oxidation of prenol was performed by Lokachari et al 12 high-pressure shock tube and rapid compression machine, were determined in a temperature range of 600−1400 K. A detailed chemical kinetic model was developed and validated with the new experimental results. Due to the lack of results in the literature, the thermal rate constants for hydrogen abstraction reactions were adopted from previous computational works or estimated with similar systems.…”