Holistic approach to anti-knock agents: A high-throughput screening of aniline-like compounds

Abstract

The increasing concerns about greenhouse gas emissions are encouraging the search for efficient combustion technologies for transportation. A valuable strategy consists of tailoring the properties of fuels through addition of additives that might increase the octane number subject to the classification, labeling and packaging regu- lation of fuel quality. In this context, we present an integrated approach involving a high-throughput screening that relies on selected physicochemical factors of aniline-like compounds, measurements of structural resem- blance and susceptibility to participate in chemical reactions with radical species, in conjunction with production viability as well as environmental and toxicological risks. This process led to a final set of representative com- pounds that were chosen to explore their behavior as anti-knock additives. The suitability of these compounds was determined through assays performed to determine the impact on fuel volatility and RON booster efficiency in conjunction with a critical assessment of their eco/toxicological risk estimated by means of a safety index. This holistic strategy led to the identification of N-methyl-p-anisidine, N',N'-diethyl-2-methyl-p-phenylenediamine and N-nitroso-diphenylamine as promising anti-knock additives. This approach is proposed as an alternative strategy to the unsupervised experimental screening of fuel additives.