Study on Volatile Organic Compounds from Diesel Engine Fueled with Palm Oil Biodiesel Blends at Low Idle Speed

Abstract

This paper presents the combustion and emissions characteristics including volatile organic compound (VOC) of a common rail direct injection diesel engine fueled with palm oil biodiesel blends contained 0%, 10%, 30%, and 100% (by volume) biodiesel at low idle speed, i.e., 750 rpm. The nitrogen oxide (NOx) emissions of biodiesel blends were lower than that of pure diesel and NOx tended to decrease as the blending ratio increased. Soot opacity and hydrocarbon (HC) were reduced with an increasing blend ratio. Carbon monoxide (CO) varied with the engine load conditions. Under low load, CO emissions tended to decrease with increasing blending ratio and increased under high load. Alkane and aromatic VOCs were mostly emitted. Benzene and tetrahydrofuran accounted for the largest percentage of total detected VOCs in all test conditions. Benzene, toluene, ethylbenzene, xylene (BTEX, toxic aromatic VOCs) were detected for all tests. Among BTEX, benzene has the highest emission ratio, followed by xylene, toluene, and ethylbenzene. Benzene increased for all tests. At low engine load, toluene, ethylbenzene, and xylene decreased with increasing blend ratio. However, these increased at high engine load. When pure palm oil biodiesel was applied at high engine load, benzene decreased.

Chromatographic Analysis of the Chemical Composition of Exhaust Gas Samples from Urban Two-Wheeled Vehicles

“…Analyses of this type require researchers to optimize sample collection and determine an appropriate analytical method. A literature review showed that scientists use a number of available methods of collecting research material and chromatographic methods, i.e., GC-MS [6][7][8][9][10][11][12][13][14], LC-MS [15], TD-GC-MS [16] with sampling into sorbent tubes [14], feeding whole air or raw exhaust gases into Tedlar bags [9,[17][18][19][20][21][22][23], microextraction into the solid phase [24], or the flame ionization method [25][26][27]. In the work of other research centers [22,23], volatile organic compounds were collected from two-wheeled vehicles into a set of Tedlar bags.…”