OXIDATIVE CLEAVAGE OF UNSATURATED BONDS OF OLEIC ACID COMPONENT IN PALM OIL VIA OZONOLYSIS REACTION

• Main Author: Novri Harahap, Astriva
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/85619
• Institution: Institut Teknologi Bandung

Oleic acid is one of the unsaturated fatty acid components in palm oil. This compound consists of 18 carbon atoms and has a cis-double bond at C-9. Indonesia is the largest palm oil producer in the world, contributing around 59% of total global palm oil production. The utilization of renewable sources such as oleic acid has an important role in the bio-based chemical industry, which is a key for the success of the sustainable development goals. Various strategies to transform oleic acid to produce useful chemicals have been achieved as the central of oleochemical industry. This can increase the economic value of palm oil. One of the strategies is the oxidative cleavage of unsaturated bonds. Ozonolysis is a reaction with high selectivity in breaking unsaturated bonds, especially in alkenes. The use of ozone as an environmentally friendly oxidizing agent is very advantageous because it does not leave dangerous residues that can pollute the environment. Ozonolysis of oleic acid is usually aimed to obtain pelargonic acid (PA), a bioherbicide, and azelaic acid (AA), which is an active ingredient in skin care products. However, ozonolysis of oleic acid with reductive work-up produces the corresponding aldehyde compounds, nonanal (NN) and 9-oxononanoic acid (ON) which can be used as building blocks in various organic materials. In this research, the unsaturated bonds of oleic acid were cleavaged through ozonolysis with reductive work-up. Firstly, PA and AA as reference compounds for this work were synthesized through the oxidation reaction of oleic acid with KMnO4. The ozonolysis reaction of oleic acid which was carried out for 10 minutes successfully broke the unsaturated bonds with a conversion of 100%. Reductive work-up of the reaction mixture yielded aldehyde products, nonanal (NN) and 9-oxononanoic acid (ON). The four standard products were purified using chromatographic technique and their structures were confirmed using 1H and 13C-NMR. Ozonolysis of oleic acid were also carried out using several reducing agents. By observation of H???? : Haldehyde integration ratio under a benchtop 1H-NMR monitoring on reaction mixtures shows that sodium thiosulfate (Na2S2O3) is the best reducing agent for reductive work-up of ozonide with ratio of 0.30. Meanwhile, sodium metabisulfite (Na2S2O5) is the least effective reducing agent with the lowest H???? : Haldehyde ratio of 0.04. Furthermore, GC-FID analysis showed that each of the four reference compounds give difference sensitivity. By using the column of HP-1, each of them was well separated with retention times of 3.98 minutes for NN, 6.33 minutes for PA, 8.25 minutes for ON, and 10.54 minutes for AA.