To check if an unconventional fuel can be burned in an engine, monitoring the stability in terms of composition is mandatory. When the composition of a conventional fuel cannot be measured for practical reason, it can be approximated using the API (American Petroleum Institute) relations (Riazi-Daubert) linking the hydrocarbon group fractions with well-chosen properties. These relations cover only the paraffin (coupling iso and normal), naphthene and aromatic (PNA) groups as they were developed for conventional fuels presenting neglected amounts of olefins and oxygenates. Olefins and oxygenates can be present in unconventional fuels. This paper presents a methodology applicable to any unconventional fuel to build a model to estimate the n-paraffin, isoparaffin, olefin, naphthene, aromatic and oxygenate (PIONAOx) composition. The current model was demonstrated for an automotive shredder residues (ASR)-derived gasoline-like fuel (GLF). The model was trained using real fractions measured with a comprehensive twodimensional gas chromatography coupled with flame ionization detector (GC × GC-FID) technique. The lowest cumulated absolute error comparing with the confidence interval of the measured fractions was evaluated to be 12.4%. The model was tested for one fuel composition only, therefore, the error of the calculated fractions will be investigated with other fuels in future work.

Waste to energy is a key driver to achieve a clean and virtuous renewable cycle. Among others, the processes to convert organic matter in wastes from automotive residues, mainly composed of rubbers and foams [ethylene propylene diene monomer (EPDM) and polyurethane (PUR)], polyolefin plastics [polypropylene (PP) and polyethylene (PE)], styrenic plastics [acrylonitrile butadiene styrene (ABS) and polystyrene (PS)], and other thermoplastics [polyvinyl chloride (PVC) and polycarbonate (PC)], into a liquid fuel are now reliable. This new, atypical, and uncharted fuel is expected to emit large levels of pollutants, bringing new challenges that must be resolved by the combustion community. Advanced combustion modes appear to be a solution to enhance the efficiency and cutoff the NO x and soot particle emissions. The present paper addresses the scarcity of experimental data by investigating the autoignition in a rapid compression machine. The pressure and temperature were swept from 10 to 20 bar and from 700 to 880 K, respectively, and the equivalence ratio was equal to 0.5. These conditions match with the homogeneous charge compression ignition (HCCI) mode operating with exhaust gas recirculation, especially for the low to intermediate (intermediate to high) temperature (pressure). The studied fuel is the light fraction of the synthetic crude oil, described by high-alkene and high-oxygenate levels. Several specificities have been detected: a limited lowtemperature reactivity and a low negative temperature coefficient. Combustion simulation will be carried out in further work to determine to what extent advanced combustion modes will play a role to achieve a clean combustion in a waste-to-energy perspective.

No abstract