1 Mass Transfer Coefficients of the Extraction Process of Essential Oil from Myrtus Communis L. Plants Using Different Solvents Ibtehal K. Shakir Chemical Eng. Dept.- College of Engineering Baghdad – Iraq ibtehal_27@yahoo.com Abstract: Essential oils are highly concentrated substances having flavor and therapeutic properties. They are used in food, cosmetic and pharmaceutical products. The main objectives of this research is to extract essential oil from different parts of Myrtus Communis L. Plants ( leaves, flowers, and stems) by solvent extraction method using water as a green solvent compared with other solvent ( n- hexane and ethanol). The description and simulation of this process with mathematical model based on mass transfer fundamentals was investigated in this research. The process parameters affected on extraction oil yield and mass transfer coefficients, when different extraction solvents were used. Results demonstrated that different parts of Myrtus Communis L. plants influence on the extraction mechanism, as well as the process controlled by mass transfer diffusion. Key words: mass transfer coefficient, solvent extraction, essential oil, Myrtus Communis L. I. INTRODUCTION Essential oils have been used by many cultures around the word for centuries. Many plants yield essential oils that may be used as perfumes, food flavorings, medicines, and pharmacy [1]. Essential oils also called volatile are mixture of hydrocarbons, alcohols, aldehydes, ketons, phenols and esters [2]. In medicine, the volatile oil obtained from different parts of Myrtus communis L. is used for decreasing glucose level in the blood. But, the therapeutic using of this plant has a little alertness payment [3]. Myrtle plants emit a pleasant odor mainly due to volatile oil that is stocked in the secretor cells, which are placed in the plants flowers, leaves and berries [4]. Myrtle is majorly used as a pectoral when the vapors produced after leaf decoction and may be used for treatment different disease like stomach ulcers, dysentery and urinary tract infections [5]. The extraction and/or fractionation of natural complex mixtures for allowing a spontaneous and complete separation of required compounds or concentrated of benefits from the extract are the main objective of research [6]. For this purpose, different extraction processes have been studied particularly to increase the essential oil yield, reduce the processing time, and moderate the consumption of energy [7]. These methods include hydro-distillation, steam distillation, microwave extraction, supercritical fluid extraction, as well as solvent extraction. The appropriateness of extraction technique differs from plant to plant [8]. Lately, using water as an extraction solvent has awful interests as a green solvent. Specially, water is cheap, environmentally genial, nontoxic, non- flammable, providing clean processing way and prevents pollution [9]. Besides, to the environmental feature to used water in state of organic solvents, separation of products is mostly simplified. Water is a polar solvent, its density, viscosity, as well as activity can weakest its solubility and the contacting with the plant matrix [10]. Varying extraction parameters can solve this problem. Volatile oil is not soluble at room temperature with water, which start-up separation by cooling, and simplifi ed the process steps. Thus, increasing the extraction temperature can be increase the interaction between solvent and the plant matrix, also the mass transfer and diffusion [11]. The principle of solvent extraction is that when solvent contacts with solid material, soluble compounds in the solid materials transfer to the solvent phase. However, solvent extraction in plant results a mass transfer of soluble volatile oil to the solvent phase from solid plant phase, by a concentration differences. When the concentration of active sites in the solvent increase the rate of mass transfer decrease, until equilibrium is reached. Then no longer mass transfer will be between the plant material and the solvent [12]. In general, a good solvent should be; dissolved the demand essential oil, having a suitable boiling point, can separated easily when extraction process finished, solvents like; ethanol, benzene, hexane, acetone, ethyl-alcohols etc.,[13] Mathematical modeling for any extraction process can be represented the principle step along operation of an active industrial process. They are The Eighth Jordan International Chemical Engineering Conference (JIChEC 2017) November 7-9, 2017