-Menthane as a Stable Terpene Derived from Orange By-Products as a Novel Solvent for Green Extraction and Solubilization of Natural Substances.

This study aims at investigating -menthane, a novel bio-based solvent resulting from the hydrogenation of d-limonene, as a green alternative to -hexane or toluene for the extraction and solubilization of natural substances. First, conductor-like combination of quantum chemistry (COSMO) coupled with statistical thermodynamics (RS) calculations show a comparable solubilization profile of -menthane and -hexane for carotene, volatile monoterpenes such as carvone and limonene, and model triglycerides. Other data obtained experimentally in solid/liquid extraction conditions further indicate that -menthane showed similar performances to -hexane for extracting carotenes from carrots, aromas from caraway seeds, and oils from rapeseeds, as these products showed a comparable composition. -Menthane was also tested using common analytical extraction procedures such as Soxhlet for determination of oil content via multiple extraction stages, and Dean-Stark for determination of water content via azeotropic distillation. For both systems, yields were comparable, but for Dean-Stark, the distillation curve slope was higher when using -menthane, and the time needed to attain 100% water recovery was 55% shorter than for toluene. Taken together, these results reveal the potential of -menthane as a green replacer for petroleum-based solvents such as -hexane or toluene.