Characteristics of CO and NOx emissions from combustion of transmethylated palm kernel oil-based biodiesel blends in a compression ignition engine

Abstract

This study assessed hazardous emissions from transesterified Palm Kernel Oil-based (PKO-based) biodiesel blends in a Compression Ignition Engine (CIE). Automotive Gas Oil (AGO) was blended with the PKO-methyl esters in the ratios 1:9; 2:8; 3:7; …; 9:1. The various blends were thereafter fired in a CIE. Besides, 100% AGO and 100% PKO-methyl esters were also burnt in the CIE. Results showed that as the concentration of the PKO biodiesel increased in the blends, carbon monoxide (CO) emissions reduced. There was about 35% significant reduction in the lethal CO emissions as the concentration of methyl esters increased in the blends at 99.9% confidence (p ≪ 0.001). At 90% confidence, there were no significant changes in NOx emissions as a result of change in blend ratios (p > 0.01). There exists a degree of association between NOx and gas temperature in agreement with Zeldovich mechanism. Keywords: Palm kernel oil, Biodiesel, Compression ignition engine, Emissions