Indonesia is currently the world’s largest palm oil producer, contributing approximately 48% of global production, followed by Malaysia with a 37% share. However, Indonesia still needs to import fatty acids—derivatives of CPO—used in various industries, such as paints, plastics, cosmetics, detergents, soaps, and foods like chocolate, ice cream, cakes, and candies. Seeing this, Mohamad Endy Yulianto, a lecturer from the Industrial Chemical Engineering Technology (TRKI) Study Program at the Vocational Faculty of Diponegoro University (Undip), took the initiative to develop domestic fatty acid production.
According to Endy, it’s important to take concrete steps to meet domestic demand for fatty acids. One of the main challenges is the production process of fatty acids, which is considered less economical. To address this, he developed a method for producing fatty acids thru hydrothermal autocatalytic hydrolysis using subcritical water. Subcritical water has advantages in hydrolysis reactions because it can act as both a reactant and a solvent. In its role as a reactant, subcritical water can form new covalent bonds with OH groups thru the transformation of organic molecules RX that react with it.
Endy also explained that subcritical water as a solvent has advantages because its solubility toward oil is higher, and it undergoes changes in physical properties—such as a decrease in dielectric constant—as the temperature increases. Under these conditions, the hydrolysis reaction takes place in a homogeneous phase, unlike conventional methods which generally produce reactions in a heterogeneous phase. As a catalyst, subcritical water is also excellent because the number of ionized water ions increases with rising temperature. The increase in the ionization constant (Kw) occurs due to the weakening of hydrogen bonds in water at temperatures above 150°C. This promotes the formation of hydronium ions (H3O+) and hydroxide ions (OH−), which can each act as acid and base catalysts.
Furthermore, Endy mentioned that in the process of hydrothermal autocatalytic hydrolysis, the free fatty acids produced from the reaction also serve as an additional catalyst. This process begins with catalysis by hydronium ions from the autoionization of water, and is then accelerated by the fatty acids formed during the reaction. Endy believes this method is highly efficient because subcritical water can perform three roles simultaneously—as a reactant, solvent, and catalyst. He hopes the results of this research can enrich science and technology, and can be developed into commercial products in Indonesia.