将增氧剂甲基叔丁基醚(MTBE)按一定比例添加到90#无铅汽油中,在汽油机台架上,考查了不同掺混比的MTBE/汽油混合燃料对电喷汽油机排放特性的影响及三效催化器的净化性能。实验结果表明,电喷汽油机掺烧MTBE后,只是在负荷很小时对CO排放有明显改善,而在其他工况下,CO排放改善效果不明显,甚至有所恶化;低速时对碳氢化合物(THC)和NOx排放有所改善;中速和高速时的改善效果不明显。催化转化器对CO和THC转化率均:能达到70%~99%,对NOx的催化转化率相对低一些,为12%~55%。三效催化器的转化率与燃料中MTBE的体积分数、汽油机转速和负荷有关。
The effect of methyl-tert -butyl ether (MTBE) addition into gasoline on the exhaust emissions from EFI gasoline engine was studied. A four-cylinder HL495IQ engine was used in the experiments. Fuels containing 0, 5%, 10%, 15%, 20% MTBE were used in the engine operations, and the exhaust gases were analyzed for CO, HC and NOx , before and after their catalytic treatment by a three-way catalytic converter. The addition of MTBE into gasoline resulted in a decrease in CO, THC and NOx emissions only at low speed or light loading. No obvious effect were observed at other conditions. Catalytic conversion efficiencies of CO and THC were inproved to 70% and 99% respectively. But the catalytic conversion rate of NOx only reached 12%-55%. The efficiency of catalytic converter had relations to speed, load of the engine and the MTBE content in the blended fuels.