A Major Loss of Phenyl Ethyl Alcohol by the Distillation Procedure of Rosa damascene Mill

Rosa damascena Mill. is an aromatic plant, having different components that usually use in natural products. The main industrial products from oil-bearing rose are rose oil, rose water, rose concrete, and rose absolute which are produced by hydro-distillation and solvent extraction processes. However, essential oil productionis the best part that the industry is eager to it. Hydro-distillation with cohobation is a widely used method for producing volatile oils from oil-bearing rose. Newly, different methods of extraction of volatile compounds of rose oil, rose water and residue water from the flower of R. damascena, such as headspace solid-phase microextraction (HS-SPME) is developed. However, every method of extraction affects the quality of Rosa product. In this way the hydro-distilled rose oil analyzed by gas chromatography (GC-FID/GC-MS) revealed that the percentages of alkanes or steaoreptens like hexadecane (1.3%), nonadecane (7.2%) and heneicosane (1.8%) were higher than those of HS-SPME. However, there is a preference of rose oil extraction by hydro- distilation that the rose water (hydrosol) and residue water have phenylethyl alcohol (PEA), which is easily soluble in water, rose water and residue water. Actually rose water is a by-products of the hydro-distillation method, and it contained very high amounts of phenylethyl alcohol and  can be employed as the best natural fragrance of the oil-bearing rose due to its very high phenylethyl alcohol content. Phenyl ethyl alcohol is a naturally occurring aromatic compound found in various flowers including roses, lavender, ylang-ylang, geranium and champagne. For determining the content of phenyl ethyl alcohol in the flower R. damascene, according to the geographical similarity, the flowers were collected from different provinces of Iran by scientists of RIFR. In a research in 2021, after the extraction of essential oil and rose water, it was conducted on the remaining water in the still. The leftover water inside the distillation pot was extracted with eight different solvents (chloroform, cyclohexane, dichloromethane, diethyl ether, ethyl acetate, hexane, petroleum ether and toluene) by a separatory funnel and extracted crude were analyzed by (GC) and  (GC/MS). The amount of phenylethyl alcohol obtained by different solvents containing chloroform, cyclohexane, dichloromethane, diethyl ether, ethyl acetate, hexane, petroleum ether and toluene was 96.1%, 46.3%, 96.1%, 46.3%, 89.6%, 100%, 0.42% and 74%, respectively. Therefore, the research revealed the phenylethyl alcohol compound can be separated from the wastewater in the still and used.