| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high-octane-number gasoline base by mixing a reformed gasoline with a low-boiling-point fraction, an intermediate-boiling-point fraction containing benzene and having a toluene concentration lower than a specified value, and a high- boiling-point fraction. SOLUTION: Reformed gasoline produced by naphtha catalytic reforming is subjected to fractional distillation to give a low-boiling-point fraction, an intermediate-boiling- point fraction containing benzene, and a high-boiling-point fraction, The low-boiling- point fraction is mixed with the high-boiling-point fraction to give a gasoline base having a benzene content of 1 vol.% or lower, an octane number higher than the reformed gasoline by at least 2, and a minimized toluene loss. The fractional distillation is conducted so that the intermediate-boiling-point fraction contains toluene in a concentration of 0.5 vol.% or lower and n-heptane in an amount (Y) satisfying equation I. In the equation, Y and X are the amounts of n-heptane and n-hexane, respectively, transferred from 100 pts.vol. reformed gasoline to the intermediate-boling-point fraction; and C is expressed by equation II [wherein R is the octane number of the reformed gasoline; A is the content (vol.%) of a fraction having a boiling point higher than that of n-hexane and lower than that of n-heptane in the reformed gasoline; and B is the vol.% of benzene in the reformed gasoline].
|
