A comprehensive study on the improvement of oxidation stability and NO_x emission levels by antioxidant addition to biodiesel blends in a light-duty diesel engine

Abstract

Moringa oleifera oil, a non-edible biodiesel feedstock with high unsaturated fatty acid content, was used in this study.

Influences of ignition improver additive on ternary (diesel-biodiesel-higher alcohol) blends thermal stability and diesel engine performance

“…When EHN are added to the treated biodiesel, HO 2 and H 2 O 2 levels decrease and negatively affect OH and CO oxidation. 2-ethylhexyl nitrate (EHN), causes the increasing of diffusion combustion mixture with locally high equivalence ratios also attributed to this [51]. The increase in CO formations with the addition of ignition improver are also in agreement with other researchers [3,44].…”

“…As a result, HC emission increases [9]. Rashed et al [51] reported about the increment in HC 7.89% by blending EHN with MB20 [51]. While Atmanli et al [3] and Ileri et al [44] reported about the decrement in HC for different proportion of EHN was added to the diesel-crude vegetable oil blends.…”

“…Few of the researcher [21,51,61] also reported about the lower smoke by implementing EHN to the alcoholic biodiesel blends. Rashed et al [51] used 1000 ppm of EHN to moringa biodiesel and found 22.56% reduction of smoke emission. Li et al [21] found lower smoke emission by mixing EHN to the biodiesel-methanol blends.…”

“…Also, mixing of alcohols and EHN in the blends gives lower viscosity and leads efficient atomization, which causes a decrease in smoke emission [60]. Few of the researcher [21,51,61] also reported about the lower smoke by implementing EHN to the alcoholic biodiesel blends. Rashed et al [51] used 1000 ppm of EHN to moringa biodiesel and found 22.56% reduction of smoke emission.…”

Effects of phenolic antioxidants on biodiesel oxidative stability and emission

“…The molecular structure of biodiesel is RC (=O) OCH 3 , in which R represents alkyl or alkenyl. The length of carbon chains in biodiesel molecular is [17][18][19], and the molecular weight of biodiesel is very close to that of diesel. The physical and chemical characteristics of biodiesel are similar.…”