Terpinen-4-ol in natural Tea tree oil (TTO) plays an important role in physiological activities. Selectively removing of 1,8-cineole and the monoterpenes such as γ-terpinene from TTO is necessary for TTO comfort and safety. In this study, the density functional theory (DFT) was employed to estimate the interaction energies between ILs and terpinen-4-ol for preliminarily screening ionic liquid type of extraction agents. It was found hexalkylguanidinium ionic liquids (ILs) [diBTMG]Br exhibited good extraction distribution coefficient of terpinen-4-ol (2.54) and higher extraction selectivity of terpinen-4-ol (6.9 to 1,8-cineole and 9 to γ-terpinene, respectively). The single extraction yield of terpinen-4-ol by the IL could reach to 90%. After the extraction, subsequent twice extractions with n-hexane and water can realize satisfactorily recovery and reuse of all extraction agents. The deterpenation of TTO has advantages of lower energy consumption, safety, environmentally friendly and less cost. It would provide an alternative strategy for the practical deterpenation production of essential oil with ionic liquids.

天然茶树油 (TTO) 中的 Terpinen-4-ol 在生理活动中起重要作用。从 TTO 中选择性去除 1,8-桉树脑和单萜（如 γ-萜品烯）对于 TTO 的舒适性和安全性是必要的。本研究采用密度泛函理论（DFT）估算离子液体与萜品烯-4-醇的相互作用能，初步筛选离子液体型萃取剂。发现六烷基胍离子液体 (ILs) [diBTMG]Br 表现出良好的萜品烯-4-醇提取分配系数 (2.54) 和更高的萜品烯-4-醇提取选择性 (6.9 至 1,8-桉树脑和 9 至 γ-分别为萜品烯）。IL对萜品烯-4-醇的单次提取率可达90%。提取后，随后用正己烷和水进行两次萃取，可实现所有萃取剂的满意回收和再利用。TTO脱脂具有能耗低、安全、环保、成本低等优点。它将为用离子液体实际脱萜生产精油提供一种替代策略。