| 摘要 |
PURPOSE:To obtain isoprene in high yield, by feeding C4 component such as isobutene, a formaldehyde source, and water to an acidic aqueous solution, evaporating the desired reaction product together with water out of the reaction zone, specifying a molar ratio of the raw material and reaction pressure. CONSTITUTION:While isobutene and/or tertiary butanol (C4), a formaldehyde (FA) source, water, and, if necessary, a low-boiling compound inert under reaction conditions are continuously or intermittently fed to an acidic aqueous solution and formed isoprene, water and other low-boiling components are evaporated out of the reaction zone, C4 is reacted with FA. In the operation, a molar ratio of the FA source to be fed calculated as C4/FA is at least 3, and the pressure in the reaction system (when the low-boiling compound is fed, its partial pressure is substracted from the pressure) is 1.1-2.5 times as high as the vapor pressure at the reaction temperature of the acidic aqueous solution, to give isoprene advantageously. |
