Refined Glycerine, also known as glycerol or glycerin, is a simple straight-chain sugar alcohol that has three hydroxyl groups, which results in water solubility and hygroscopicity of glycerin. This is a clear, colorless, odorless, high boiling, viscous liquid. It is naturally sweet and has low toxicity. It has a typical melting point and boiling point of 17.8°C and 290°C, respectively. Refined Glycerine density is 1.26 g/cm³. It comes from petrochemical feedstock. Due to its low toxicity and environmental friendliness, it is used in many applications such as food, medicine, cosmetics, and personal care items. It is also a versatile and valuable product from biodiesel production.
Palm fruit collected from the fields are threshed to remove the main stem and the spikelets attached to the fruit.
The palm fruit undergoes sterilization. Sterilization is conducted by applying steam to the fruit. The high temperature treatment is to prevent oil splitting enzymes to undergo hydrolysis and oxidation of the oil. In addition, the applied steam allows the moisture within the fruit to expand. The expanded moisture helps to easily detach the kernel, gum, and resin from the walls of the fruit.
The sterilized palm fruits are digested through the process of mixing and pounding. A rotating shift is used to mechanically mix the fruit under high temperature. As the palm fruit is broken down into pulp. The cells of the fruit are also broken down to release the desired palm oil. The heat added to the digester to allow easier mixing due to low viscosity of oil in high temperature.
The processed palm fruit is pressed to extract palm oil. A large hydraulic machine is used to apply pressure to the palm fruit on a heavy metal cage. As pressure is applied to the pulp, palm oil is secreted from the material and collected for further processing.
The extracted palm oil is further processed through a series of purification procedures. As there is still remaining moisture, cell debris, and fibrous, the oil is added with hot water. The water added allows large solids to trickle down from the oil phase. The elevated temperature of water assists the breaking down of the emulsion of water and oil. Next, the mixture is filtered to remove the remaining solids left. Finally, the separated layer of water and oil is decanted to collect the required palm oil for storage and processing.
Solvent extraction of palm oil is required to remove the free fatty acid by deacidification process. The palm oil is mixed in methanol by agitation. The existing free fatty acid will preferably dissolve in methanol instead of palm oil and will decrease the concentration. As free fatty acid is the cause of the oxidation and unpleasant scent of the oil, it is essential to remove the compound from the oil to promote storage time and refining.
The deacidified palm oil is decomposed by hydrolysis reaction under high temperature and pressure. The process utilizes water to break down the chains of triglycerides into glycerol/glycerine and chains of fatty acid. In this step, glycerine becomes available for extraction; however, further refining is required for the newly made glycerine to be called refined glycerine.
The mixture of glycerine and chain of fatty acids is further refined by a series of separation processes. The oil mixture is distilled to separate the fatty acids from the desired glycerine. The distillation column is heated to promote evaporation of both glycerol and fatty acid. Glycerine has lower boiling point; therefore, glycerine will evaporate readily at a certain range temperature whereas the chains of fatty acid will remain as liquid.
The extracted mixture of glycerine is not fully refined as leftover methanol has not been removed from the deacidification process; therefore, evaporating the methanol from the glycerine is required to produce a readily refined glycerine.
Glycerine is widely used as a raw material for pharmaceutical purposes. The chemical compound has contributed to heart medication, suppositories, cough remedies and anesthetics. In addition, glycerine has a laxative properties that are able to improve digested food to flow smoothly along the lining of the stomach.
In cosmetic products, glycerine retains water to maintain product softness, creaminess, and storage life. Glycerin’s low vapor pressure allows the compound to persist when moisture continuously releases to the surroundings.
In athletics, glycerine drink is used to help water hydration in athletes during exercise. It is also mainly used as a raw ingredient to be a sweetener.
Glycerine has been recently researched to provide an intermediary product for fuel additives. Fuel additives are used to decrease harmful emission by utilizing oxygenated glycerin derivative fuel additives. On the other hand, the lubricating properties of glycerine are used to enhance machine performance and reduce friction. The friction reduction allows heat to dissipate and prevent machinery from overheating. In addition, the economic viability of utilizing glycerin is another reason for to be used as a chemical intermediate and industrial applications.