Effect of antioxidant on the performance and emission characteristics of a diesel engine fueled with palm biodiesel blends

Improving oxidation stability and NOX reduction of biodiesel blends using aromatic and synthetic antioxidant in a light duty diesel engine

“…From this investigation it is shown that for the addition of the three antioxidants, with CIB20 the average BSFC lessens significantly. Same trends were recently found from various biodiesel blends, like the palm species Calophyllum inophyllum (Rizwanul Fattah et al, 2014a;Rizwanul Fattah et al, 2014b). The reduction of BSFC might be due to the properties of the amines, which improved ignition quality caused by the presence of oxygen content, as well as the low viscosity and low density of the test blends (Palash et al, 2014;Varatharajan and Cheralathan, 2013).…”

“…Higher CN contributes to an earlier combustion with conditions like post flame oxidation (PFO), larger flame speed (LFS) and so on (Varatharajan et al, 2011). HC reduces remarkably when borne oxygen enlarge the unburned of HC oxidation at the fuel-rich region (Ozsezen et al, 2009;Rizwanul Fattah et al, 2014a). From Fig.…”

“…The main reason for increasing CO emissions with antioxidant in biodiesel, is that the antioxidant additive lessens the capability of CO oxidation when the oxidation process occurs, followed by an extensive release of hydrogen peroxide (H 2 O 2 ) and peroxyl radical (HO 2 ). But these radicals are converted again into hydroxyl radicals (OH) during the combustion process by absorbing heat from the combustion chamber, converting CO into CO 2 (Palash et al, 2014;Rizwanul Fattah et al, 2014a). When the antioxidant additives, NPPD, DPPD and EHN are added to Moringa biodiesel, HO 2 and H 2 O 2 are reduced and they negatively impact the OH, as well as the oxidation of CO. Fig.…”

“…As a result, CIB20, CIB20 + NPPD, CIB20 + DPPD and CIB20 + EHN produced a maximum lower output power of 4.5%, 1.7%, 3.30% and 2.03%, respectively, compared to diesel. CIB20 biodiesel blend produces lower power output because of its higher kinematic viscosity, which makes it undergo poor combustion, although its molecular structure contain more oxygen content than diesel (Aydin and Bayindir, 2010;Rizwanul Fattah et al, 2014a). Hence, the average BP for tested blends is 6.37 kW, 6.58 kW, 6.48 kW and 6.55 KW for diesel, CIB20, CIB20 + NPPD, CIB20 + DPPD and CIB20 + EHN, respectively which was 5.23%, 2.08%, 3.70% and 2.52% lower on average compared to diesel.…”

Influence of metal contaminants and antioxidant additives on storage stability of biodiesel produced from non-edible oils of Eastern Africa origin (Croton megalocarpus and Moringa oleifera oils)

“…An antioxidant is a chemical that delays the start or slows the rate of the oxidation reaction [21]. It inhibits the formation of free radicals or interrupts the propagation of free radicals and hence contributes to the stabilization of the biodiesel [22].…”