In my process after extraction we collect organic layer which is a mixture of THF,MED and 10% of water, we are trying to seperate them by using distillation on distillation column to recover the solvents and reuse in the process. But actually it is not possible to seperate completly MED and THF seperatly. 0.5% of any is allowed in recovered solvent but practically we are unable to sepeate them up to required specifications, so kindly guide in this regards.