Study on the Characterisitics and Formation MEchanisms of Combustion Exhaust Gas of Methanol Fuel

甲醇燃烧废气的特性及形成机理FuelAn在甲醇燃料燃烧反应器（石英玻璃流反应器：模型装置）和实际发动机在各种燃烧条件下的实验燃烧结果的基础上，试图阐明甲醇燃料燃烧废气的特性及形成机理。此外，利用电子自旋共振（ESR）自旋捕获技术对甲醇燃料废气产生的气相自由基s进行了详细的研究。用0.1mol/苯溶液捕获废气，在室温下记录其ESR谱。主要研究结果如下：以实际发动机为例，在实际运行（5-20ps）时，随着排气管温度的升高，甲醛和未燃烧甲醇的平均排放量仅占很小的质量。燃烧产生的气相自由基的形成浓度与废气温度密切相关。燃烧产生的气相自由基主要有氧自由基和烷基自由基。在模型装置中，发现甲醇燃料在470℃左右点火时发生着火燃烧，甲醛浓度达到最大值，并产生气相自由基。证实气相自由基与实际发动机中发现的成分相同。由上可知，甲醇燃料的燃烧反应方案是通过氧基自由基（RO）进行的，其形成机理可归因于燃烧的气相自由基。

Characteristics and Formation MEchanisms of Combustion Exhaust Gas of MEthanol FuelAn attempted elucidation of the characteristics and formation mechanisms of combustion exhaust gas of methanol fuel was undertaken on the basic of the results obtained from the experimental combustion of methanol fuel by using a combustion reactor(a quarts glass flow reactor : model apparatus) and a practical engine under various condition of combustion.In addition, gas-phase radical sgenerated from the exhaust gas of methanol fuel were studied in detail using the electron spin resonance(ESR) spin-trapping technique. The exhaust gas was trapped with phenyl-N-t-butylnitron(PBN) 0.1mol/benzene solution, and its ESR spectrum was recorded at room temperature.The main results are follows.1. In the case of practical engine, it was found that average emissions of formaldehyde and unburned methanol constituted only little mass under the practical runiing(5-20ps) with higher temperature of exhaust tube. The close correlation was observed between the formation concentration of gas-phase radicals from combustion and the temperature of exhaust gas. The gas-phase radicals generated from combustion were found to be alcoxy radical and alkyl radical.2. In the case of model apparatus, it was found that ignition and combustion of methanol fuel occurred at about 470ﾟC of ignition temperature while the concentration of formaldehyde reached to the maximum amout, under producing gas-phase radicals. The gas-phase radicals were confirmed to be the same components as found in the practical engine.3. It can be concluded from the above that combustion reaction scheme of methanol fuel proceeds via alcoxy radical(RO) and the formation mechanism is attributable to the gas-phase radicals of combustion.