The Effect Of MMT For Light-duty Vehicles Emission And Environment

Because of the boom of the vehicles number, mobile sources emission becomes more and more serious. It has become the most important sources of atmospheric pollution in urban. For controlling vehicle emission and improving urban air quality, the strict regulations had been implemented by our government. The fuel quality has direct effects on vehicle emission. The additive usually has been used to ameliorate fuel specifications, but there are drastic debates about MMT as replacer of TEL to enhance gasoline octane. The debates focus on the effects of MMT's combustion products on engine and emission control system operation smoothly, tailpipe emission, human health and environment.Lots of work had been done for resolving above debates. Firstly, a great deal of data and references bad been investigated to comprehend the category, emission and effects of MMT's combustion products. The results indicated that the MMT's combustion products are maked up of solid inorganic compounds, such as Mn-oxide, Mn-sulfate, Mn-sulflde and Mn-phosphate. Only about 10%-30% products will be emitted as PM into atmosphere through tailpipe, but most parts will deposit on surface of engine, exhaust system and catalytic converter.Secondly, to discuss the emission effects of MMT fuel additive on vehicles under the condition of state III (Euro III) emission standard, six passenger cars (600cpi TWC, Euro IV, original OBD) divided into two groups run 8×10~4km with MMT and without MMT respectively, and the comparison of two groups' vehicles emission testing results was made. The results showed that the emission deterioration trend of two groups' vehicles was very similar. During the beginning 2×10~4km, the emission deterioration was sharply increased, but was stable in the residual mile. Additionally, to describe the emission control system parts' deterioration condition, the emission tests were carried out under the conditions that the original TWCs were replaced respectively by a new and an old one and the six aged TWCs were fixed to a same new car. According to the additional emission tests, the deterioration of TWC was worst among all of the parts of the emission control system and had no obvious...