| 摘要 |
Disclosed is a method for extraction in a process for production of a 2-alkyl-l,3-propanediol, 2,2-dialkyl- 1,3 -propanediol, 2-alkyl-2-hydroxyalkyl-l,3-propanediol or 2,2-dihydroxialkyl- -1,3-propanediol. Said method comprises the steps of (i) feeding a mother liquid, obtained in a process for synthesis of a said di, tri or polyhydric alcohol, at a controlled mass flow to a first extraction unit, (ii) extracting said mother liquid in said first extraction unit in at least one high boiling solvent effective in extracting organic by-products, (iii) obtaining a raffmate and an extract comprising said solvent and organic by-products, (iv) recycling said raffmate to said process, (v) feeding at a controlled mass flow obtained extract to a second extraction unit, (vi) extracting said extract in water, (vii) obtaining a water phase comprising said organic by-products and a solvent phase, and (viii) recycling said solvent phase. |
