New Octane Booster Molecules for Modern Gasoline Composition

Abstract

In the framework of reducing GHG emissions and accelerating the decarbonization of the road transport sector, vehicle efficiency is a key factor for competitiveness. In this sense, the refining industry can make its contribution by reformulating high-octane petrol fuel. The impact of this type of gasoline from CO2 emission balance, technical feasibility, and economics standpoints has recently been assessed by the petroleum industry with promising results, and new potential boosters that could improve the octane number of standard gasoline are more needed than ever. The present work summarizes a comprehensive review aimed at collecting available data regarding chemical molecules that can be used in advanced gasoline formulations for modern spark-ignited car engines focusing on ash-free technologies. Potential boosters are divided into two categories: high-octane gasoline components and octane enhancer additives, with 2 vol % the considered frontier concentration between them. Targeted chemical compounds examined in the screening for high-octane components include isoparaffins, olefins, aromatics, alcohols, ethers, esters, ketones, furans, and carbonates. Chemical families assessed as additives were anilines, hydrazines, amines, pyridines, quinolines, indoles, N-nitrosamines, iodine compounds, selenium compounds, phenols, formates, oxalates, and, in lesser extension, other families. The scope of the analysis includes not only anti-knock effectiveness but also associated side effects for the engine, possible effects on both human health and the environment, current applications, and compatibility with existing infrastructure, among others. Promising opportunities in the medium- and long-terms for every family of chemical compounds that can potentially improve the anti-knock character of modern gasolines well beyond current specifications worldwide are presented. Furthermore, a few chemical families are identified as the most promising ones to be used in future gasoline formulations, either as high-octane components (such as ethers, ketones, and esters) or as octane booster additives (such as anilines, N-nitrosamines, and phenols).

Artificial intelligence-driven design of fuel mixtures

“…In all blends, except for mixture 6-1, cycloalkenes ( cyclohexene , ethylidene , and cyclopentane ) and phenol ethers ( anisole and phenetole ) are present. Both families involve high-octane sensitivity compounds, put forward as potential octane boosters 39 – 41 . For certain mixtures (18-17, 26-20), primarily C 5 -C 6 alkyl esters are present because lighter esters (such as methyl acetate ) exhibit insufficient octane sensitivity.…”

Graph Machine Learning for Design of High-Octane Fuels

“…The known RON + OS scores from literature for ethane and 3-ethyltoluene of 122 and 124, respectively, are in good agreement with the GNN predictions. Three ethers are identified, including methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE) that are used as octane boosters in practical applications (Demirbas et al, 2015;Badia et al, 2021). Their experimentally RON + OS scores of 135 and 134 (Leppard, 1991;Kubic et al, 2017) are slightly higher than the predicted scores.…”

“…For modern SI engines, fuels with both high RON and high OS, hence high OI, are desired as they enable engine operation at conditions associated with particularly high efficiency (Kalghatgi, 2005;Bell, 2010;Mittal and Heywood, 2008;Amer et al, 2012;Kalghatgi, 2014;Szybist and Splitter, 2017;Abdul-Manan et al, 2018). To boost the OI of a fuel, chemical species with high RON and high OS such as ethanol and MTBE can be added (Demirbas et al, 2015;Badia et al, 2021). Identification of further molecules providing octane boosting is of great practical relevance and is studied actively, e.g., see (Badia et al, 2021;.…”

“…To boost the OI of a fuel, chemical species with high RON and high OS such as ethanol and MTBE can be added (Demirbas et al, 2015;Badia et al, 2021). Identification of further molecules providing octane boosting is of great practical relevance and is studied actively, e.g., see (Badia et al, 2021;. Herein, we aim to identify such promising candidates exhibiting both high RON and high OS by computeraided molecular design (CAMD).…”

Conversion of Sugar Diacetyls to Bio-Hydrocarbons by the Catalytic Cracking in a Fixed Bed with Fresh and Deactivated Beta Zeolite

“…The oxygenates are mainly Table 5 Conversion and yields of liquid, gas, coke, unreacted n-hexane, and water obtained by catalytic cracking of pure n-hexane and 10% DX/ n-hexane in Beta a zeolites hydrothermally treated at different temperatures. ketones, furans and alkyl-furans, which can be used as gasoline octane boosters [26]. The largest amount of oxygenates from the 30 wt% DX mixture were ketones.…”