THE STUDY OF DEGRADATION AND STABILIZATION OF EPOXIDIZED PALM OIL Ms. Thitimaporn Duangmanee National Metal and Materials Technology Center

What is epoxidized palm oil (EPO)? Why is EPO interesting? How to produce and test the EPO? How about the study? What is the conclusion from the study?  Introduction  Objectives  Experiments  Results & Discussion  Conclusions Contents 2

Epoxidized Vegetable Oil  Epoxidation is the epoxide functional group consists of a three- member ring with two carbon atoms and one oxygen atom.  Epoxides are most commonly synthesized from reacting alkenes with peracids. 3

Applications of Epoxides  Raw materials for variety of chemicals such as alcohols and glycols  Stabilizers for PVC to improve stability  Improve properties of polymers towards heat and UV radiation  Improve elasticity of plastics  Replace materials derived from petroleum 4 Readily Available Biodegradable Environmental Friendly RenewableLow Cost

Mechanism of Epoxidation 5 Main reaction Side- reaction  The reaction steps were suggested by Gan et al. in 1992, using carboxylic peracid in an acidic environment, with hydrogen peroxide as showed in main reaction.  The side-reaction show oxirane ring cleavage to glycol that are degradation reactions of the oxirane ring on the yield of the epoxidation process.

 The plantation area and product of palm trend to increase every year from year Palm oil in Thailand Crude palm production in Thailand, year

Objectives 7 Stabilized EPO using an antioxidant Epoxidized Palm Oil (EPO) using Epoxidation Refined Palm Oil  Side reactions of epoxidation process lead to decrease of % oxirane oxygen and formation of glycol.  Minimization of side reactions effect need to be done to maintain high % oxirane oxygen(epoxides).  Proposed solution:  Addition of antioxidants in EPO Antioxidant is normally being used in food for longer storage period and prevent oxidation of oil or fats in food.

Raw Material & Chemicals  Palm oil was manufactured by Siam Oil & Fat. Co., Ltd. (Samut sakhon, Thailand).  Antioxidants  Butylatedhydroxyanisole (BHA)  Tert-butylhydroquinone (TBHQ)  Propyl Gallate Gallussäure-propylester (PG)  For synthesis  Glacial acetic acid (AA),  30 wt% aqueous hydrogen peroxide,  32wt% solution Hydrogen bromide in acetic acid  Sulfuric acid were obtained from Merck.  For %Oxirane oxygen using the titration method ( AOCS Cd 9-57)  HBr in acetic acid was diluted with glacial acetic acid to prepare 0.1 N HBr.  Crytal violet solution was used as an indicator.  For Glycol using the titration method (May, “Epoxy resins: chemistry and Technology”, 1973 )  Chloroform  Benzyltrimethylammonium periodate used as Oxidation Reagent  Sodium thiosulfate solution  Potassium iodide  Starch solution 8

Properties of Palm Oil  Palm oil feedstock was determined fatty acid composition that refined palm oil was selected as raw material for this study. 9 Fatty acid Composition (% wt) RefinedNon-refined Lauric acid methyl ester C12:0 Myristic acid methyl ester C14:0 Palmitic acid methyl ester C16:0 Stearic acid methyl ester C18:0 Arachidic acid methyl ester C20:0 Saturated Palmitoleic acid methyl ester C16:1 Oleic acid methyl ester C18:1 Linoleic acid methyl ester C18:2 Linolenic acid methyl ester C18:3 Eicosenoic acid methyl ester C20:1 Unsaturated Total Fatty Acid100.0

Synthesis of EPO g of palm oil is poured into round-bottom flask, heated up to 65 o C and stirred at 1400 rpm Calculated amount of acetic acid and sulfuric acid are added and the mixture is stirred for 30 minutes 30% aqueous solution H2O2 is added slowly and the reaction is continued for 30 minutes Mixture is washed until the pH reaches 7 Remaining water is separated by using Oil Test Centrifuge and is removed with sodium sulphate anhydrous crystals

Stabilization of EPO Test for 12 weeks Text in here Text in here EPO + TBHQ EPO + TBHQ EPO + PG EPO + PG EPO + BHA EPO + BHA 11

Changes of %Oxirane Oxygen  All EPO had decreased. EPO without antioxidant has the highest percentage oxirane oxygen.  Antioxidants had lead to a more rapid opening of oxirane ring and faster degradation of EPO. 12

Changes of glycol 13  Degradation of EPO synthesized leads to the production of glycol.  The testing of glycol amount for 12 weeks, the glycol amounts for EPO was rather not very consistent.  Glycol amount decreased at the first half of the 12 weeks and increased at Week 7.

Hygroscopic Characteristics of Glycol  Glycol has a strong affinity towards water molecules due to the formation of weak electrostatic absorbing power known as H-bond by the electronegativity of the atoms.  In addition, glycol can react with acetic acid form ethylene glycol monoaceate and water. 14

Conclusions 15 It was possible to produce epoxidized oil from palm oil Three types of antioxidants into the EPO synthesized has no significant effect on the glycol amount Antioxidants will result in greater opening of oxirane rings and thus reduce the %Oxirane oxygen. Antioxidants cannot be used to prevent the degradation of the epoxidized palm oil.

Acknowledgment National Metal and Materials Technology Center (MTEC) a member of National Science and Technology Development Agency (NSTDA) Many thanks to Mr. Tan Seng Yee from Universiti Teknologi PETRONAS, Malaysia and Mr. Athip Achalanant from Thammasat University, Thailand for experiment and testing.