METHOD FOR PRODUCING GLYCOLS FROM OXIRANE COMPOUND

摘要

There is provided a method for producing dipropylene glycol and/or tripropylene glycol, the method comprising steps (A), (B), (C), (D), and (E) defined below,
step (A): the step of reacting a raw material liquid comprising propylene oxide and water to obtain a reaction liquid comprising unreacted water, propylene glycol, dipropylene glycol and/or tripropylene glycol, and an alcohol compound excluding propylene glycol, dipropylene glycol, and tripropylene glycol,
step (B): the step of separating, from the reaction liquid, a first liquid containing water and the alcohol compound and a second liquid containing the propylene glycol and the dipropylene glycol and/or tripropylene glycol and optionally containing the alcohol compound,
step (C): the step of removing at least a part of the alcohol compound from the first liquid to obtain a third liquid containing water and optionally containing a part of the alcohol compound,
step (D): the step of separating, from the second liquid, a fourth liquid containing the propylene glycol and optionally containing the alcohol compound, and a fifth liquid containing the dipropylene glycol and/or tripropylene glycol and optionally containing the alcohol compound,
step (E): the step of recycling at least a part of the third liquid to step (A) as a component of the raw material liquid.