8/11/2019 April - Petrochemical - Analysis and Identification of Fatty Acid Methyl Ester Composition in Different Vegetable Oil

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EXPERIMENTAL

NOTESClarus600 C GC-MS

Analysis and Idenificaion of Faty

Acid Mehyl Eser Composiion inDifferen Vegeable Oil (Biodiesel)Source Using Gas Chromaography Mass Specromery

Abstract

Vegetable oils have been attracted attention has a potential renewable source for the

production of an alternative for-petroleum based diesel fuel. Various products obtained

from vegetable oils have been proposed as an alternative fuel for diesel engines,including neat vegetable oil, mixtures of vegetable oil with petroleum diesel fuel and

alcohol esters of vegetable oils. Out of which Alcohol esters of vegetable oils appear to

be the most promising alternative. Vegetable oils are triglycerides (glycerin esters) of fatty

acids and alcohol esters of fatty acids have been prepared by the transesterification of

the glycerides, wherein linear, monohydroxy alcohols reacts with the vegetable oils in

the presence of catalyst to produce alcohol esters of vegetable oil. The alcohol esters of

vegetable oil when used as an alternative diesel fuel have been identified as a biodiesel.

This experimental note demonstrates the analytical capability of PerkinElmer Clarus

600C GC-MS for the analysis and identification of fatty acid methyl ester composition

(Biodiesel) in various vegetable oils.

Author

Dileep Kumar Mamidala

Applicaion Specialis ChromaographyCenre of Excellence for Analyical SciencesPerkinElmer (India) Pv. Ld.Hyderabad 500 081 India.Email: applicaion.india @perkinelmer.com

GC-PERO-002

Preparation of biodiesel

Transesterification:

Weighed about 250 g of Kusum oil, Palash oil, Mehwa oil and

Thumba oil and transferred in to individual 100 mL conical flasks.

Weigh about 2.5 g of Potassium Hydroxide (1% by weight of

the oil) and dissolve it in 72 g anhydrous methanol. Completely

dissolve the KOH in methanol, apply heat if required. transfer

8/11/2019 April - Petrochemical - Analysis and Identification of Fatty Acid Methyl Ester Composition in Different Vegetable Oil

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the resulting solution slowly to the sample in a conical flask with

stirring. After complete transfer of KOH solution in methanol

continue the stirring for 120 minutes to complete the reaction.

After completion of the reaction time pipette out and transfer

approximately 8-10 mL of reaction mixture to 15mL test tube

and keep it for phase separation.

Phase separation and washing:

After 120 minutes of reaction time, the reaction was stopped andreaction mixture was allowed to stand overnight while the phase

separations occurred in different reaction mixtures in individual

flasks. The ester phase was decanted from the mixture and

transferred to glass column for further washing to remove the any

traces of methanolic KOH solution.

Excess alcohol and residual catalyst were washed from the ester

with water. The ester phase was placed in a glass column 1.26 cm

in diameter and 100 cm in length. Water was sprayed into the top

of the column at a low velocity. The excess alcohol and catalyst

were removed by the water as it percolated through the column.

During the washing, some of the ester formed an emulsion with

the water; a time of 24-48 hours was required for the waterphase containing alcohol, catalyst, and emulsified ester to settle

and the ester phase to become clear.

Sample preparation and analysis:

Weigh 25 mg of the ester phases of different oils and dissolve

it in 0.5 mL of n-heptane. The resulting sample solution is filled

in GC auto sampler vial and injected in GC/MS to analyze and

identify the fatty acid methyl ester composition in different types

of vegetable oils.

Instrumental Conditions:

Clarus 680 GC Optimized Experimental Conditions

Column Elite-5MS, 30m x 0.25mm x 0.25um

Injector temperature 220 C

Carrier gas Helium

Carrier gas flow 0.2 mL/min

Split ratio 50:1

Oven Programme 35 C hold for 10 min10 C/min 200 C hold for 10 min

Total run time 36.5 min

Diluent n-Heptane

Injection volume 0.1 ul

Clarus 600 C MS Parameters

Ionization source EI

Electron energy 70 eV

Source temperature 200 C

Transfer line temp 200 C

Multiplier (V) 366 V

Ion energy 1.5 V

Scan range 10-600 m/z

Analytical results & discussion

Biodiesel samples were analyzed using PerkinElmer Clarus 600

C GC-MS in total scan mode to identify the fatty acid methyl ester

composition in different vegetable oil sources with the help of

NIST library. The samples were analyzed and the composition of

fatty acid methyl esters was identified were as follows.

Fig 1. oal ion chromaogram of Palashbiodiesel. 1. Caprylic acid mehyleser, 2. Myrisic acid, mehyl eser,3. Palmioleic acid, mehyl eser, 4.Palmiic acid, mehyl eser, 5. Margaricacid, mehyl eser, 6. Linoleic acid,mehyl eser, 7. Oleic acid, mehyleser, 8. Searic acid, mehyl eser,9. 11-Eicosenoic acid, mehyl eser,10. Arachidic acid, mehyl eser, 11.Heneicosanoic acid, mehyl eser, 12.13-Docosenoic acid, mehyl eser,13. Behenic acid, mehyl eser, 14.ricosanoic acid, mehyl eser, 15.Lignoseric acid, mehyl eser, 16.Penacosanoic acid, mehyl eser, 17.Ceroic acid, mehyl eser.

Fig 3. oal ion chromaogram of Kusumbiodiesel. 1. Palmioleic acid, mehyleser, 2. Palmiic acid, mehyl eser, 3.Linoleic acid, mehyl eser, 4. Oleic acid,mehyl eser, 5. Searic acid, mehyleser, 6. 11-Eicosenoic acid, mehyleser, 7. Cis-11-Eicosenoic acid, mehyleser, 8. Arachidic acid, mehyl eser, 9.Heneicosanoic acid, mehyl eser, 10.13-Docosenoic acid, mehyl eser, 11.Mehyl 11-docosenae, 12. Behenic acid,mehyl eser, 13. Lignoseric acid, mehyleser.

Fig 4. oal ion chromaogram ofTumba biodiesel. 1. Caprylic acidmehyl eser, 2.Azelaaldehydic acid,mehyl eser, 3. Myrisic acid, mehyleser, 4. Penadecanoic acid, mehyleser, 5. Palmioleic acid, mehyl eser, 6.Palmiic acid, mehyl eser, 7. Margaricacid, mehyl eser, 8. Linoleic acid,mehyl eser, 9. Oleic acid, mehyleser, 10. Searic acid, mehyl eser,11. 13-Docosenoic acid, mehyl eser,12. Behenic acid, mehyl eser, 13.Lignoseric acid, mehyl eser.

Fig 2. oal ion chromaogram ofMehwa biodiesel. 1. Caprylic acidmehyl eser, 2. Myrisic acid, mehyleser, 3. Palmiic acid, mehyl eser, 4.Margaric acid, mehyl eser, 5. Linoleicacid, mehyl eser, 6. Oleic acid, mehyleser, 7. Searic acid, mehyl eser, 8.11-Eicosenoic acid, mehyl eser, 9.

Arachidic acid, mehyl eser, 10. Behenicacid, mehyl eser, 11. Lignoseric acid,mehyl eser, 12. Penacosanoic acid,mehyl eser, 13. Ceroic acid, mehyleser.

ConclusionsThis experimental result confirms the effectiveness of the

analysis procedure and also demonstrated the capability of

PerkinElmer Clarus 600 C GC-MS to identify the fatty acid

methyl ester composition (biodiesel) in different types of

vegetable oil sources.