Study On Oxidation Stability And Emission Characteristics Of Biodiesel With Antioxidants

Biodiesel, as a clean alternative fuel, has been widely concerned in the word. Because biodiesel is a mixture made up of saturated and unsaturated fatty acid methyl ester, oxidation stability of biodiesel is poor. Scholars at home and abroad have carried on many attempts and research to improve the oxidation stability of biodiesel.In this paper, the antioxidant BHA, BHT, TBHQ were added into B10(10 vol.% biodiesel and 90 vol.% diesel), the biodiesel/diesel mixed fuel. The purpose of the experiment is to improve the oxidative stability of B10 by adding antioxidants and study on effect of BHA, BHT, TBHQ on the oxidation stability of B10. According to the measured results, selecting two kinds of antioxidants to add into B10 and conducts the power, fuel economy, emission characteristics of the engine test.The research has shown the following results: Firstly, the induction period of B10 without adding antioxidant is 2.77 h and far lower than the induction period of 6h of the national standard NB/SH/T0873-2013. The induction period of B10 increases with the increase of addition amount of BHA, BHT,TBHQ.Secondly, the results of engine full-load characteristic show that the power and torque of the engine fueled with B10 added BHA and BHT are slightly higher than those of the engine fueled with B10 without any antioxidants, while the specific fuel consumption is lower. In the engine load characteristic at 2000 r/min, the test of load characteristic indicates that the specific fuel consumption of the engine fueled with B10 in which the mass concentrations of BHA and BHT are 400mg/L is slightly higher than that of the engine fueled with B10 without any antioxidants. However, when the mass concentrations of BHA and BHT in B10 are 800mg/L or 1200mg/L, the fuel consumption rate is lower than that of B10 without adding antioxidants.Thirdly, at the speed of 2000r/min, the test of load characteristic shows that NOX emission of the engine fueled with B10 with BHA or BHT is higher, compared with the engine fueled with B10 without any antioxidants. However, HC, soot emissions and PM are lower than that of B10 without adding antioxidants. Meanwhile, HC emission of the B10 with BHA is lower than that of the B10 with BHT. For the B10 with BHT, with the increase of BHT, soot emission and PM increases. Whether B10 with antioxidants or not, CO emission of the engine fueled with B10 is very low, approaching zero.