Research Journal of Agriculture and Environmental Management. Vol. 3(10), pp. 511-518, October, 2014 Available online at http://www.apexjournal.org ISSN 2315 - 8719© 2014 Apex Journal International Full Length Research Study of hydro-distillation process of Ruta chalepensis L. essential oil Jamel Mejri 1,2 * , Iheb Chakroun 3 , Manef Abderrabba 1 , and Mondher Mejri 1 1 Laboratoire Matériaux Molécules et Applications, Institut Préparatoire des Etudes Scientifiques et Techniques, IPEST, BP51, La Marsa 2070, Tunisia. 2 Département Génie Mécanique et Agro-Industriel, Ecole Supérieure des Ingénieurs de l’Equipement Rural, ESIER, 9070 Medjez el Bab, Tunisia. 3 Ecole Supérieure des Industries Alimentaires de Tunis, Cité El Khadhra Tunis – 1003, Tunisia. Accepted 15 September, 2014 The hydrodistillation of essential oil from aerial part of Ruta chalepensis L. (rue oil) was studied. Two models were applied: first order kinetic model and Monod model. Models were evaluated to predict the recovered essential oil. Process parameters optimization for hydrodistillation was reported. The hydrodistillation did not follow very well the first order kinetic model. Monod model kinetic was shown to simulate hydrodistillation rue oil. The highest oil yield was obtained during the period extending from March to April with a hydrodistillation duration superior to 100 minutes. It was observed that yield can be modeled as function of growth stage. GC-MS analysis showed that the major constituent of the oil was 2-undecanone (77.7%). Key words: Ruta chalepensis L., Essential oil, Hydrodistillation, Kinetic, Monod model, Simulation. INTRODUCTION Essential oils have extensively been studied because of their commercial interest (Da Porto et al., 2009). They have been employed in the fragrance industry, in aromatherapy, in pharmaceutical preparations and in food manufacturing as functional ingredients (Rezzoug et al., 2005; Magwa et al., 2005; Tepe et al., 2005; Chemat et al., 2006; Cassel et al., 2009). The development of essential oil sector has a direct relation with the improvement of process technology in industrial plants (Cassel et al., 2009). Hydrodistillation is normally used to isolate essential oils from aromatic and medicinal plants (Velickovic et al., 2008). A common characteristic of the processes of extraction and purification of natural products is the need to know the system, which allows the definition of the process operation conditions (Teixeira de Souza et al., 2008). For a possible industrial application, the optimization and the *Corresponding author. E-mail: jmejri2001@yahoo.fr Tel: +216 97 577 532; Fax: + 216 78 561 700 assessment of the extraction process with mathematical modeling seem to be essential (Liu et al., 2009). This experimental methodology combines mathematics with statistics for generating a mathematical model to describe the process, analyzing the effects of the independent variables and optimizing the processing operations (Liu et al., 2009). Different mathematical models were used to simulate hydrodistillation and steam distillation of essential oil. Such models were used to generalize the experimental results. Benyoussef et al. (2002) showed that the kinetic model simulates very well essential oil hydrodistillation from coriander seeds than diffusional model. Hanci et al. (2003) proposed a logarithmic model. Koul et al. (2004) shows that extraction of oil by steam distillation of grass follows first order kinetics. However, Babu and Singh (2009) demonstrated that the oil produced by hydrodistillation from E. cinerea did not follow the first order kinetic model, but the process can be simulated by Langmuir gas adsorption model. Works of Cassel et al. (2009) indicated that diffusional model fitted very well the experimental data for the essential oil recovered by