Methanol autoignition temperature

F]), cyclohexane (245 C [473°F]), re-pentane (260°C [500°F]), ethanol (365°C [689°F]), methanol (385 C [725 F]), and isopropanol (399°C [750 F]). Table IX.l provides flash point and autoignition temperature data for some common flammable compounds. The flammability data for these compounds, as well as those of other flammable and combustible substances, are presented throughout this book. 

The series of alcohols in Table 5.1.2.3—methanol, ethanol, 1-propanol, and 1-butanol—illustrates the relationship between molecular structure and chemical properties. Among these four alcohols, the boiling points, autoignition temperatures, and flash points increase while vapor pressures decrease, as the molecular weights of these compounds increase within this chemical class with the same functional groups (alcohol or —OH). In this series the vapor pressure decreases with increasing molecular weight. 

Methanol is highly inflammable, having a National Fire Proteetion Association (NFP A) fire hazard rating of 3 [54] in a seale from 0 to 4 (0 corresponds to noncombustible and 4 to extreme inflammable). Methanol vapor evolved at room temperature may form an explosive mixture with air over a wide ran of eoncentration (5.544%). Methanol has a flash point of 11°C and an autoignition temperature of 464°C. It has a reported burning rate of 1.7 mm/min [17]. 

The low toxicity of DME is comparable to that of liquid propane. Comparatively, methanol is toxic upon skin contact and ingestion. Dimethyl ether has a higher autoignition temperature and lower flammability limit than gasoline [61], however. 

The engine was the first to incorporate compression ignition of alcohols (7). Low cetane fuels can autoignite, however, provided the in-cylinder temperature is high enough and fuel injection correcdy timed. This compression ignition works for methanol as well as ethanol and gasoline. 

Flash point and autoignition point depend on methanol content. Flash point methanol-free 80 C 10% methanol 60X 15% methanol 50° C. Explosive limits are for methanol-free. Log P octanol/water is estimated. Minimum storage temperature (to avoid polymerization) 1 % methanol ... 

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