Refined Glycerine – Vegetable Based
The degumming process of vegetable oil involves the removal of phosphatides from vegetable oil by centrifugation. Water is added in the mixture to allow the precipitation of phosphatides dissolved in oil. The precipitated phosphatides become heavier in mass due to the high water content absorbed. The centrifugation process allows phosphatides to migrate to the water phase; therefore, removing impurities in the oil. Degumming is required to refine the quality of the vegetable oil and allows longer storage time.
The vegetable oils undergo deacidification through a series of solvent extraction processes. The initial vegetable oil is mixed in methanol by agitation. The existing free fatty acid in the oil will preferably dissolve in methanol and decrease the concentration in the oil. 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 oil is decomposed through a process called hydrolysis. The process utilizes water to break down the chains of triglycerides into glycerol/glycerine and fatty acid under high temperature and pressure. In this step, glycerine becomes available for extraction and undergoes further refining.
Glycerine pre treatment
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 glycerine and fatty acid. Glycerine has higher 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.