Affiliations: Research Center for Eco-Environmental Sciences,
Chinese Academy of Sciences, Beijing 100085, China | State Key Laboratory of Automotive Safety and Energy,
Tsinghua University, Beijing 100084, China
Abstract: The preparation of ethanol-diesel fuel blends and their emission
characteristics were investigated. Results showed the absolute ethanol can
dissolve in diesel fuel at an arbitrary ratio and a small quantity of water
(0.2%) addition can lead to the phase separation of blends. An organic additive
was synthesized and it can develop the ability of resistance to water and
maintain the stability of ethanol-diesel-trace amounts of water system. The
emission characteristics of 10%, 20%, and 30% ethanol-diesel fuel blends, with
or without additives, were compared with those of diesel fuel in a direct
injection (DI) diesel engine. The experimental results indicated that the blend
of ethanol with diesel fuel significantly reduced the concentrations of smoke,
hydrocarbon (HC), and carbon monoxide (CO) in exhaust gas. Using 20%
ethanol-diesel fuel blend with the additive of 2% of the total volume, the
optimum mixing ratio was achieved, at which the bench diesel engine testing
showed a significant decrease in exhaust gas. Bosch smoke number was reduced by
55%, HC emission by 70%, and CO emission by 45%, at 13 kW/1540 r/min. However,
ethanol-diesel fuel blends produced a few ppm acetaldehydes and more ethanol in
exhaust gas.
