Separation of borneol/camphor natural products mixture with MIL-101(Cr)

Background: Natural products are valuable resources for drugs research and development. The separation and purification of particular drug molecule from multiple structural analogs remains a great challenge. Borneol is a natural product widely used for the treatment of the cardiovascular and cerebrovascular diseases. It is very challenging to be purified due to the presence of camphor with similar molecular structure, which limits the supply of high-purity borneol. Methods: Seven kinds of metal-organic frameworks (MOFs) are used for the first time to explore the borneol/ camphor mixture separation. The adsorption kinetics and isotherms of borneol and camphor for MIL-101(Cr) were evaluated. Significant findings: Among these MOFs, MIL-101(Cr) exhibited the best performance with the borneol/camphor selectivity of 4.3 and the borneol adsorption capacity of 495 mg & sdot;g (- 1) at 298 K. The fast adsorption kinetics with the equilibrium time of 30 min at 298 K enabled high separation efficiency under dynamic conditions. The highpurity borneol (> 98 %) can be obtained through the three-stage purification processes. Furthermore, the material is stable and reusable for multiple cycles without obvious decrease of the performance, indicating high potential for practical application.