Lignin derivatives as potential octane boosters

Owing to environmental and health concerns, tetraethyl lead was gradually phased out from the early 1970's to mid-1990's in most developed countries. Advances in refining, leading to more aromatics (via reformate) and iso-paraffins such as iso-octane, along with the introduction of (bio) oxygenates such as MTBE, ETBE and ethanol, facilitated the removal of lead without sacrificing RON and MON. In recent years, however, legislation has been moving in the direction of curbing aromatic and olefin content in gasoline, owing to similar concerns as was the case for lead. Meanwhile, concerns over global warming and energy security have motivated research into renewable fuels. Amongst which are those derived from biomass. The feedstock of interest in this study is lignin, which, together with hemicellulose and cellulose, is amongst the most abundant organic compounds on the planet. Contrary to (hemi-) cellulose, however, which is an important constituent of feed for livestock, lignin falls completely outside of our food chain. This study was motivated by the need for renewable octane boosters of low toxicity, which improve both anti-knock quality and fuel economy under modern engines conditions. The goal of this study is to investigate on a Volvo T5 spark ignition engine whether or not the lignin derived aromatic oxygenates, benzyl alcohol, 2-phenyl ethanol and acetophenone, adhere to such requirements. It was found that these aromatic oxygenates have a low toxicity and improve both knock resistance and volumetric fuel economy under modern engine operating conditions