This work was conducted to study the extraction of eucalyptus oil from natural plants (Eucalyptus camadulensis leaves) by organic solvents. the effects of the main operating parameters were studied; type of solvent (n-hexane and ethanol), time to reach equilibrium, the temperature (45˚C to 65˚C) for n-hexane and (45˚C to 75˚C) for ethanol, solvent to solid ratio (5:1 to 8:1 (v/w)), agitation speed (0 to 900 rpm) and the particle size (0.5 to 2.5 cm) of fresh leaves to find the best processing conditions for the achieving maximum oil yield. The concentration of eucalyptus oil in solvent was measured by using UV-spectrophotometer. The results (for n-hexane) showed that the agitation speed of 900 rpm, temperature 65˚C with solvent to solid ratio 7:1 (v/w) of particle size 0.5 cm for 210 minute give the highest value of oil (68.5 wt%). Similar conditions for ethanol with the exception of the temperature (75˚C) give the highest yield of oil (65.07 wt%).

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This work studied the textual properties of the MCM-48 and rice husk ash using nitrogen adsorption-desorption at constant low temperatures. According to the International Union of Pure and Applied Chemistry, the adsorption-desorption isotherm proved that the studied materials have a mesoporous structure with type IV. The obtained results of Langmuir, Freundlich, and Brunauer-Emmett-Teller isotherm models showed that the nitrogen adsorption followed Brunauer-Emmett-Teller isotherm. The found adsorption capacity and surface area values for MCM-48 were higher than those values for rice husk ash. Based on the Kelvin equation, Barrett, Joyner, and Halenda model was used to determine pore size distribution, pore diameter, and average pore volume for the adsorbents. The pore size distribution for MCM-48 was narrower than rice husk ash, pore diameter for MCM-48 was less than rice husk ash, and average pore volume for MCM-48 was higher than the value of average pore volume for rice hush ash. The comparison study results between the properties and those previously published for mesoporous materials indicated a convergence in the surface area of MCM-48 and pore volume. Moreover, the results of the comparison between the properties of rice husk ash showed that the surface area and pore volume were equal or less than those obtained before.

This work aims to study extraction of essential oil (EO) from peppermint leaves using hydro-distillation methods. The peppermint oil extraction with hydro-distillation method studied the effect of the extraction temperature on the yield of peppermint oil. Besides, it also studied the kinetics during the extraction process. The second-order mechanism was adopted in the model of hydro-distillation to estimate many parameters such as the initial extraction rate, capacity of extraction, the constant rat of extraction at various temperatures and activation energy. The results showed that the extraction process is a spontaneous process, since the Gibbs free energy has a negative value at all studied temperatures. For example the Gibbs free energy at (70, 80, 90, and 100 ºC)were (-2.93, -3.84, -4.75, -5.66) respectively.

The extraction of Basil oil from Iraqi Ocimum basillicum leaves using n-hexane and petroleum ether as organic solvents were studied and compared. The concentration of oil has been determined in a variety of extraction temperatures and agitation speed. The solvent to solid ratio effect has been studied in order to evaluate the concentration of Ocimum basillicum oil. The optimum experimental conditions for the oil extraction were established as follows: n-hexane as organic solvent, 60 °C extraction temperature, 300 rpm agitation speed and 40:1 mL:g amount of solvent to solid ratio.