A liquid containing 25 mol % toluene, 40 mol % ethylbenzene, and 35 mol % water is subjected to a continuous flash distillation at a total pressure of 0.5 atm. Vapor pressure data for these substances are given in Table 21.4. Assuming that mixtures of eth ylbenzene and toluene obey Raoult's law and that the hydrocarbons are completely immiscible in water, calculate the temperature and compositions of liquid and vapor phases 

(a) At the bubble point, 

(b) At the dew point, 

(c) At the 50 percent point (one-half of the feed leaves as vapor and the other half as liquid).

Table 21.4:

Transcribed Image Text:

TABLE 21.4 Vapor pressures of ethylbenzene, toluene, and water Vapor pressure, mm Hg Toluene Temperature, "C 50 60 70 80 90 100 110 110.6 120 Ethylbenzene 35.2 55.5 84.8 125.8 181.9 257.0 353.3 481.8 139.5 202.4 289.4 404.6 557.2 760.0 Water 92.5 149.4 233.7 355.1 525.8 760.0