Effect of diesel and pentanol blends on PAH formation and regulated pollutants

Abstract

The necessity of using oxygenated fuel blends in diesel engines has become apparent in recent years as one of the leading emission reduction approaches. Among such fuels, high-carbon alcohols, including n-pentanol, may serve as potential additives to reduce regulated and unregulated emissions. The aim of this study is to understand the effects of diesel fuel and n-pentanol blends (5%, 20% and 35% by volume: DPen5, DPen20, DPen35) on regulated emissions and polycyclic aromatic hydrocarbons (PAHs). These blends were tested in a diesel engine under three different load conditions and regulated emissions were determined. The PAH emissions of the exhaust gases were collected at idle and quantified using the gas chromatography–mass spectrometry (GC-MS) technique. Compared to neat diesel, the blended fuels, with their addition of n-pentanol, showed a significant reduction of up to 16.52% in nitrogen oxides (NOx) emissions. Additionally, decreases of up to 42.02% in total PAH emissions were obtained with 35% pentanol addition. For all blends, a significant reduction in higher cyclic PAHs was noted. Overall, diesel-pentanol blends were effective in reducing nitrous oxides, carcinogenic pollutants, and further, the possibility of engine malfunction operating at low load or cold operating conditions.