Separation of D-Limonene and Other Oxygenated Compounds from Orange Essential Oil by Molecular Distillation and Fractional Distillation with a Wiped Film Evaporator

Orange essential oil (OEO) is mainly composed of D-Limonene and other oxygenated compounds that contribute to the orange flavor and aroma. However, D-Limonene is unstable in the presence of heat, light, and water, affecting the quality of the OEO. Therefore, the objective of this study was to fractionate OEO by distillation, both molecular and fractionated (hybrid), producing a D-Limonene-rich fraction. The OEO was characterized by physicochemical tests and gas chromatography combined with mass spectrometry (GC-MS). The fractionation of the OEO was carried out by molecular distillation and fractional distillation following, in both cases, a factorial design (2(3)) with central points, considering the D-Limonene percentage in the distillate and the residue as a response variable. According to the physicochemical characterization, the predominant optical isomer was dextrorotatory, where D-Limonene is the main component of OEO (92.584%). For molecular distillation, the D-Limonene content was reduced to 47.964% in the residue or deterpenated fraction, while for fractional distillation, it was 86.779%. For this study, molecular distillation was considered a non-thermal process (use of low temperatures) that promoted the efficient recovery of oxygenated compounds. In contrast, fractional distillation favored the recovery of D-Limonene in the light fraction.