An-Najah National University Chemical Engineering Department Graduation Project Extraction of Essential Oils Prepared by Mohammad Jarrar Mohammad Yaseen Tareq Bourini Yazid Husni Odeh Supervisor Dr.Husni Odeh

 Objectives  The aim of our project is to extract oils from seeds such as : lemon, pumpkin, aniseed and grape. And from plants such as :thyme, lavender, sage, rosemary, mint, lemon peels and leaves.  Essential oils have an economical value, marketing value and industrial value in both local and international markets.

Definition

 Essential Oils  Essential oils may be defined as volatile odoriferous oils of vegetables origin.  Essential oils are aromatic substances widely used in the Perfume industry, Food and Flavoring, Cosmetics, and Pharmaceutical Products.  They have high value in economic since they enter a wide range of industry.

 Extraction Methods 1. Distillation includes : Steam distillation. Water distillation. 2. Expression (cold pressing) 3. Solvent extraction. 4. Maceration. 5. Enfluerage. 6. Super critical carbon dioxide.

 Extraction oils from some plants and seeds:  Plants ( by steam distillation) Rosemary, Sage, Thyme, Mint, Lavender, Lemon Peel and Lemon Leaves.  Seeds (by solvent extraction) Grape seeds, Aniseeds, Lemon seeds and Pumpkin seeds. Mint

 Solvent extraction: Essential oils can be extracted by using solvents such as ethanol and hexane.

 Steam Distillation  The hot steam helps to release the aromatic molecules from the plant material since the steam forces open the pockets in which the oils are kept in it.

 The plants and seeds are :  Rosemary  Sage  Lavender  Thyme

 Mint Lemon leaves  Jasmine Lemon seeds  Lemon peel Aniseed

 Rosemary oil is effective for asthma, bronchitis and whooping cough.  Some of its products are rosemary oil hair shampoos.  Sage oil  It is effective to stimulate the digestion and specially a bad appetite.  Sage oil filled in bottles and used as lotion.  Rosemary oil

 Grape seeds oil  It treats a range of health problems including dark cycles under eyes, diabetes and hypertension.  Jasmine Oil  The jasmine oil used for coughing and nervous debility, treats headaches, eliminate the stress and depression.

 Mint Oil  Mint oil is excellent for mental fatigue and depression, refreshing the spirit and stimulating mental ability and improving concentration.  Pumpkin seeds oil  In treating cancer, leukemia, sclerosis, or various diseases which are hard to cure, pumpkin seeds have an energizing role. And also used in treating the prostate

 Aniseed oil  Aniseed oil is widely used as flavoring ingredients in all major categories. It also is used to flavor tobacco products, mouthwashes and toothpaste and Aniseed oil soap.  Lemon peel oil  Lemon oil can be used in a base cream, in a lotion or as a mouthwash, for mouth ulcers and throat infections and for oily skin and it is used as air sterilizer.

 Lemon leaves oil  Lemon leaves oil are used in cosmetics products.  It is used in popular floral perfumes and body scents.  Thyme oil It fortifies the lungs and helps with colds, coughs, asthma, whooping cough and sore throats.

 Lavender oil  It is very effective for treating headache, acne, athlete's foot and earache.  Lavender oil has many products mainly in cosmetics.  Lemon seed oil` It is mainly used in cosmetics

 Solvent extraction ◦ This method was used to extract oil from different seeds (lemon seed, aniseed, pumpkin seed and grape seed) at room temperature and using ethanol and n-hexane as a solvents. The next figure shows the main steps for extraction essential oil:

 Main solvent extraction steps

 Amount of 150 g lemon seeds were grinded in house grinder and put in 1000 ml beaker, then amount of 450 ml ethanol was poured to them, so the solid liquid ratio is roughly 1:3.  A mixture of grinded seed and ethanol were mixed in the beaker by using mixer for three hours.  Suction filtration was used in order to separate the liquid from other solid material.  Rotary evaporator device was used to separate the oil from the ethanol.

 10 ml of pure lemon seeds oil was obtained from this experiment.  In addition of lemon seed oil, pure oil was extracted from different seeds such as ( pumpkin seed, aniseed and grape seed) by using different quantities and two different solvents (ethanol and n-hexane).

Steam distillation Steam distillation

 Steam distillation apparatus was modified by adding a valve in the bottom of the apparatus. Each type of treated plants was collected before doing its experiment, and then the bad parts were removed, after that the plant was cleaned perfectly and cut for small pieces. The steam generator was switched on to produce steam for the experiment, the treated plant was put in the apparatus after it was prepared, cooling water valve was switched on for condensing vapor and the steam was introduced from the bottom of the retort at low flow.

The liquid produced was filled in bottle as shown in figure below:

Separation the oils from condensed liquid: Normal hexane was added to the condensed liquid and it was mixed together, two layers were appeared by using separatory funnel; the first layer is water and the second layer is oil and solvent. The oil was separated from the solvent by using rotary evaporator.

In many cases when the amount of oil was relatively enough (>2ml), the oil is sucked by using dropper. This is the best method to recover more than 80% of the oil gathered at the top surface of water. This was practical method to separate rosemary oil, lemon peels, mint and lavender.

The following figure shows sample of mint oil at the surface of the liquid:

 The seeds are grinded by using an electrical machine to increase the surface area at which the contact between the solvent and the grinded seeds occur to get the largest amount of oil, the grinded seeds and the solvent was placed under the mixer in beaker for about 3 hours in order to achieve good mixing and to improve the contact between them.  The suction filtration was used in order to separate the liquid which contains the oil and the solvent from the solid part. The rotary evaporator was used to separate the oil from the solvent and it was operated under vacuum pressure to allow solvent removal at low temperature.

Quantities of oil extracted by different seeds

Steam distillation The steam was operated at low flow to minimize the amount of water produced; the treated plant was cut for small parts to allow the steam to open the pockets which contain oil. Three condensers were used; the first one is installed on the apparatus, the second one is coil in cold path of water and the third one is flask in cold path of water to get the largest possible quantity of oil and to halt any escape of essential oil from the system. The temperature and pressure were carefully controlled to avoid burning the oil and it was about 100 C and 1 bar.

The amount of oil extracted and process condition:

Steam distillation method was used for extraction the essential oil from plants which are Sage, rosemary, thyme, lavender, lemon leaves and lemon peel since this method is very suitable and the hot steam was able to open the pockets in which the oil exist. Solvent extraction method was used for extraction the essential oil from lemon seeds, aniseeds, pumpkin seeds and grape seeds and this method give the largest possible amount of oil and the solvent used in it available and it can be removed by rotary evaporator.

In steam distillation apparatus, condensation process was modified by installing another two condensers in order to catch the high volatile oil which is very volatile and can escape rapidly from the system In order to increase the amount of oil and prevent losing of the volatile oil, the coil must be modified to prevent accumulation of water and to get the quantity of oil produced without losing. The next figure shows the modification process: