The invention relates to an extraction, rectification and
separation method and an extraction, rectification and
separation process for a
solvent containing a
tetrahydrofuran-carbinol
system which take
ethylene glycol as an extractions
solvent, and take
tetrahydrofuran and carbinol as products. In the
drug synthesis process in the
pharmaceutical industry, a great quantity of solvents containing the
tetrahydrofuran, the carbinol and the like are used, and a mixed
liquid waste is generated. Under the normal temperature and normal pressure, the boiling temperatures of the tetrahydrofuran and the carbinol are extremely similar (the boiling temperature of the tetrahydrofuran is 65.4 DEG C and the boiling temperature of the carbinol is 64.8 DEG C), so that the tetrahydrofuran and the carbinol are difficult to separate by adopting a common rectification operation. In addition, the tetrahydrofuran and the carbinol are good in intersolubility and can be well dissolved with great majority of organic or inorganic solvents so as to be incapable of being separated by an extraction operation. According to the method and the process, the waste
solvent containing the tetrahydrofuran-carbinol
system can be recovered by adopting an extraction and rectification manner, meanwhile, an extracting agent is recycled, so that the obtained tetrahydrofuran and carbinol products are high in purity, impurities are few, the recovered solvent can be recycled in the
drug synthesis process, further not only is the cost of
pharmacy process reduced, and also the
pollution of the waste solvent to the environment is alleviated greatly.