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

3

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.

4

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

Readily Available

Biodegradable

Environmental

Friendly

Renewable

Low Cost

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Mechanism of Epoxidation

Main reaction

Side- reaction

RCOOH + H2O2 +R CO

O

OHH2O 1

R CO

O

OH+ C C RCOOH C

OC+ 2

CO

C + H2OH+

C C

OH OH

3

CO

C + RCOOHH+

OH

C C

OCOR

4

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 2006-2011.

Palm oil in Thailand

Crude palm production in Thailand, year 2006-2011

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Objectives

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.

8

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

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Properties of Palm Oil

Palm oil feedstock was determined fatty acid composition that refined palm oil was selected as raw material for this study.

Fatty acidComposition (% wt)

Refined Non-refinedLauric acid methyl ester C12:0Myristic acid methyl ester C14:0Palmitic acid methyl ester C16:0Stearic acid methyl ester C18:0Arachidic acid methyl ester C20:0

Saturated

0.2430.798

39.3893.9150.200

44.545

0.2550.920

42.6114.0760.264

48.126

Palmitoleic acid methyl ester C16:1Oleic acid methyl ester C18:1Linoleic acid methyl ester C18:2Linolenic acid methyl ester C18:3Eicosenoic acid methyl ester C20:1

Unsaturated

0.06143.82911.3210.1680.076

55.455

0.09040.62110.855

0.2140.095

51.875

Total Fatty Acid 100.0 100.0

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Synthesis of EPO

200 g of palm oil is poured into round-bottom flask, heated up to 65oC 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

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Stabilization of EPO

Test for 12 weeks

Text in hereText

in here

EPO+

TBHQ

EPO+

TBHQ

EPO+

PG

EPO+

PG

EPO+

BHA

EPO+

BHA

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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.

0 1 2 3 4 5 6 7 8 9 10 11 121

1.2

1.4

1.6

1.8

2

2.2

EPO BHA

TBHQ PG

Week

% O

xira

ne

Oxy

gen

Changes of glycol

13

0 1 2 3 4 5 6 7 8 9 10 11 120.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

0.045

0.050

EPO

BHA

TBHQ

PG

Week

Gly

colA

mou

nt

(mol

es/1

00g)

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.

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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.

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Conclusions

It was possible to produce epoxidized oil from palm oil

Three types of antioxidants into the EPO synthesized has no significant effect on the glycolamount

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.