Synthesis of Nonionic Surfactant from Benzoic Acid and Palmitic Acid

Rasyidah Binti A Rozi (43810)

Bachelor of Science with Honours (Resource Chemistry)

2016

Borma PTA4

Saya ~M\j104~ ~ INTI PI t2.0:l..l (nama) 00. pelajar

, ~~ 111 mengalru telab membuat perubahan yangperlu* I4iElak aee­

peFY9ahaa terhadap Laporan Projek Tabun Akhir yang bertajuk:

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Bersama ini saya kemukakan 3 salinan Laporan Projek Tahun Ak:bir dan 1 salinan

'softcopy' Laporan berkenaan.

Tandatangan Pelajar Tandatangan Penyelia

l«tWCI

faculty Df Itesoun:e Science and T~) UNIVERSITI MALAYSIA SARAWAK

."3IOKotaS~ PeDgesahaD

Tandatangan.Ketua Program

ff; (Nama & Cop Rasmi) .

Dr Devaci K_Ofll~" Pfo&TImmc- ('P"l'rdhl;lt\lr Departmcnl ,.' • '!'l' ll '; II'

* -potODg )'IIDg 1idak berkaitaJI FlCUltv .f~es(lur't· '-: " · 1 ' . • ' " "UNivERSITI ;·.1\ 1 . . ' ., ',' .

SYNTHESIS OF NONIONIC SURFACTANT FROM PALMITIC ACID AND

BENZOIC ACID

RASYIDAH BINTI A ROZI

(43810)

A Final Year Project report is submitted in partial fulfillment of the requirement for the award

of the degree of Bachelor in Science (Resource Chemistry)

Supervisor:

Madam Amira Satirawaty Binti Mohd Pauzan

Department of Chemistry

Faculty of Resource Science and Technology

UNIVERSITI MALAYSIA SARA W AK

2016

Acknowledgement

First of all, I want to express my gratitude to Allah Taala for giving me healthy body

and mind to complete this project with ease. My gratitude also goes especially to my

supervisor, Madam Amira Satirawaty Binti Mohd Pauzan for her guidance, support,

motivation and advices along the project completion. Thanks also to the lab assistant, Encik

Rajuna, FTIR technician, Encik Wahab and NMR technician, Puan Norhayati, for guidance,

help and support in using the all the machine and apparatus in the laboratory. Last and not

least, thank you to my family for support and understanding, also to lllY friends and laboratory

mates for always being by my side during ups and downs in completing this project.

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Table of content

Acknowledgement............................................................ .......................... I

Declaration... .................... ........... .... .... ... ............ ... .............. .... ... ......... II-III

Table of Contents.. . . . . . .. . . . . .. . . . . . . . . . . . . .. . . . . . .. . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. IV-VI

List of Abbreviations ..... ........... .... ....... ....... .... ........................ .. ........ .... VII-VIII

List of Tables and Schemes. . . . .. . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .. . . . . . .. . . . IX

List of Figures... ... ...... .. . ... ... ...... ...... ......... ............ ............... ...... ... ..... X-XI

Abstract. ...... ,....... '" ., . .. . ...... ... ....... ... .. . , ........ , . .. , '" .. , '" ..................... .

Introduction......... ............ ...... .. . ...... ...... ... .. .. .... . ... ... .. . ...... ... ... ...... ...... 2-3

Literature Review. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4

2.1 Benzoic Acid... ...... .. .. .... . ... ... ... ......... ... ... ...... ... ... .. . ............. 4-5

2.2 Palmitic Acid...... ................ ... ........ .... .. .................. ......... ... .. 6

2.3 Polyethylene Glycol (PEG)........................ .............................. 7-8

2.4 Surfactant ........ .. . ......... .... .... . ..... .. '" ..... , . . . . . . . . . . . . .. . . . . .. . . . . . .. .. 9-10

2.4.1 Nonionic Surfactant.... .... .... ......... ............... ......... ... ... 11

2.5 Synthesis of Non ionic Surfactant................................ ...... .... ..... 12-13

2.6 Characteristics of Surfactant. .. . . . . . . . . . . . . .. . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . .. . . 13

2.6.1 Surface Tensio 13

2.6.2 Wetting time.................. ... ....................... ......... ....... 13

2.6.3 Cloud Point... ... ...... ...... ......... ................................ 14

2.6.4 Foam.................................................................... 14

2.6.5 Emulsion.. ... ... ..... ..... ... ............ . .. .. ..... .. ...... ..... ........ 14

2.6.6 Critical Micelle Concentration (CMC)............................. 15

IV

Materials and Methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.1 Materials ......... ............ .. .. . .. . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.2 Methods............ .... .... .......... ... ...... .. . ......... .... ... .... ... .... .... .... . 16

3.2.1 Purifying Benzoic Acid .. ..... ... . . ..... . ........ .. .. ......... ..... . .. .. 16-18

3.1 .2 Synthesis of PEG fatty ester... ... ... ... ... ... ...... ... ... ... ... .. . .... 18

3.1.3 Synthesis ofNonionic Surfactant... ... ... ... ... . ........ ... ... ... .... 19-20

3.3 Chemical Analysis... ............. ... ... . . ......... ...... .... ..... ... ... ... .. .. .. ... 21

3.3.1 The Characterization ofNonionic Surfactant ............ ........ . .. . 21

3.3.2 Thin Layer Chromatography (TLC) Test ... ... ............ ... ... .... 21

3.3.3 The Analysis of Cloud Point ofNon ionic Surfactant......... ... ... 21

3.3.4 The Analysis of Wetting Time of Non ionic Surfactant.. . ... ... ... 21

3.3.5 The Analysis of Foam and Foam Stability... .. . ... ... ... ... ... ... ... 22

3.3.6 The Analysis of Emulsion Stability . .. '" ... ... ... ...... ... ... ........ 22

3.4 Percentage Yield... ...... ...... .. . ... .. . . ..... ...... ... ... ... ...... . .. ... ... .. . ... .... 22

Results and Discussion. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . . 23

4.1 Purifying Benzoic Acid... ...... ......... ... ...... .. . ............... ... ... ... . .. .... 23-24

4.2 Synthesis of PEG Palmitic Ester. .... . ..... ................... . .. ................. 24-25

4.3 Synthesis ofNonionic Su...tant......... ... ...... ... ... ... ... ... ... ... . ...... 25-26

4.4 Chemical Analysis... .. . . . ....... ............... ... ... ......... ... .. . ... ... ... ....... 26

4.4.1 Fourier-Transform Infrared (FTIR) Characterization...... ... ... .... 26-29

4.4.2 IH NMR Characterization... ... ......... ... ... ... ... ......... . ... .. ... .... 29-31

4.4.3 l3C NMR Characterization. ....... .... . .. .. .... . . . ...... . ........ . ...... 31-32

4.4.4 TLC Test.. . ......... ... ... ... ... ......... ..... . ... ... ... ..... . ... .. ... . ..... 32-33

4.4.5 Cloud Point.... .. ... ............ ... ... ... .. . ...... ... ......... ......... .... 33

V

4.4.6 Wetting Time.................. .................................... ... .... 33

4.4.7 Foam and Foam Stability... .. ..................................... ... 33-34

4.4.8 Emulsion Stability... ...... ...... ... ... ... ... .. . ... ... .. ...... . . .. ... . .. . 34

Conclusion... .. . ... ........ ... .... ... .......... ........... ........ .. ................ . ... ......... . 35

Recommendation........ .. ..... .. . ......... .. .... ... ... ... ... ... ... ... ... ... ...... ... ...... .... 35

References.. ............. ... ...... ...... ... ... . .. ... ...... ...... . . .. ..... ... ... . .. ... ... ... ... .... 36-39

Appendices

VI

B.C

CMC

coch

fTIR

F

g/mol

g/cm3

g

H20

HLB

H-NMR

IUPAC

KOH

KBr

M

mL

mm

MHz

NMR

NaOH

Na2S03

NaCI

OIW

List of Abbreviation

before century

Critical Micelle Concentration

Chloroform

Fourier Transform Infrared Spectrometer

Farenheit

gram per mol

gram per centimeter cubes

gram

water

hydrophile-lipophile balance

Proton Nuclear Magnetic Resonance

International Union of Pure and Applied Chemistry

potassium hydroxide

potassium bromide

molar

milliliter

millime",

mega Hertz

Nuclear Magnetic Resonance

sodium hydroxide

sodium sulfate

sodium chloride

oil in water

VII

W/O

PEG

POE

p-toluene sulphonic acid

sp.

TLC

TMS

wt%

%

o

water in oil

polyethylene glycol

polyoxyethylene

para toluene sulphonic acid

Species

Thin Layer Chromatography

tetra methyl silane

weight percentage

percentage

degree (angle)

degree Celcius

VIII

List of Tables and Scheme

No Tides Pages

Scheme 3.1 Esterification of palmitic acid and PEG 200 19

Scheme 3.2 The fonnation of nonionic surfactant 20

Table 4.1 Foam Stability 34

IX

List of Figures

Figures Titles Pages

42.1 Structure of benzoic acid

52.2 The fonnation of benzoic acid

2.3 The structure of palmitic acid 6

2.4 Structure of PEG 200 7

2.5 Surfactants characteristics 9

2.6 Types of micelle of surfactants 10

2.7 Types of surfactants 10

3.1 The set-up for recrystallization of benzoic acid 16

3.2 (a) The dissolved and filtered benzoic acid was placed in the ice 17

bath.

(b) The crystals fonned was collected and stored in glass

bottles.

3.3 Benzoic acid in capillary tube for melting point analysis. 18

3.4 The reflux was set in Dean-Stark apparatus set-up for both 20

esterification and fonnation of nonionic surfactant

4.1 (a) Impure benz<1iaacid 23

(b) Pure benzoic acid

4.2 PEG palmitic ester 25

4.3 Nonionic surfactant 26

274.4 FfIR spectra of benzoic acid

284.5 FTIR spectra of PEG palmitic ester

x

29FfIR spectra of nonionic surfactant 4.6

30NMR peaks for PEG palmitic ester 4.7

31NMR peaks for nonionic surfactant 4.8

324.9 I C-NMR of PEG palmitic ester

4.10 The set-up for TLC test 33

XI

Synthesis of Nonionic Surfactant from Benzoic Acid and Palmitic Acid

Rasyidah Binti A Rozi

Abstract

Surfactant or surface active agent is commonly used nowadays but it still affected our health

and envirorunent. According to previous study, the solution for the problem is the uses of

nonionic surfactant compared to other types of surfactant. The objective of the study is to

synthesis non ionic surfactant from palmitic acid and benzoic acid. The nonionic surfactant

synthesized through the intermediate, PEG palmitic ester formed from palmitic acid and

polyethylene glycol 200 (PEG 200) before it was reacted with benzoic acid. The synthesized

nonionic surfactant was analyzed and confIrmed its structure by using FTIR, TLC test, 13C_

NMR and IH-NMR. The characteristics of the nonionic surfactant were investigated; cloud

point (62°q, wetting time (20.59 s), foam and foam stability (16.67%) and emulsion stability

(18.85 s).

Keywords: Nonionic surfactant, Benzoic acid, Palmitic acid, PEG 200, FTIR.

Abstrak

Surfaktan atau bahan aktifpermukaan selalu digunakan pada masa kini tetapi ia memberi

kesan terhadap kesihatan dan alam sekitar kita. Berdasarkan permehatian terdahulu,

penyelesaian untuk masalah ini adalah dengan penggllnaan surfaktan bukan inonik

berbanding surfaktan jenis yang lain. Objekt~fkajian ini adalah untuk menghasilkan sllrfaktan

bukan ionik daripada asid palmitik dan asid benzoik. Surfaktan bukan ionik dihasilkan melalui

perantaraan, PEG ester palmitik y~ terhasil daripada asid palmitik dan polietilina glikol

200 (PEG 200) sebelum ia ditindakbalaskan dengan asid benzoik. Sur/aktan bukan ionik yang

terhasil telah dianalisis dan dipastikan strukturnya menggunakan FTIR, ujian TLC, J3C-NMR

dan I H-NMR. Ciri-ciri sur/aktan bukan ionik dikaji; titik kekeruhan (62°C), tempoh basahan

(20.59 s), pembuihan dan kestabilan buih (16.67%) dan kestabilan emulsi (18. 85s).

Kata /cunei: Surfaktan bukan ionic, Asid benzoik, Asidpalmitik, PEG 200, FTIR.

1

Introdnction

Surfactant is a short tenn for surface active agent. Surfactant has been used by human since as

early as 2800 B.C. Surfactants have two parts. The tail is hydrophobic that is usually a long

chain hydrocarbon and the head is hydrophilic which is ionic or strongly polar groups. It is

divided into four types which are anionic, cationic, nonionic and amphoteric surfactant. The

discussion in this report is focused on nonionic surfactant. Nonionic surfactant is a surfactant

with no charges and has been produced worldwide since problems associated with surfactants

arise 35 years ago (Haigh, 1996).

Nonionic surfactant produced nowadays has been widely used for many sectors of

industries like cosmetics and detergents production industries. Since the environmental

consent arise regarding surfactant usage, active researches on surfactant have been made by

many scientists to lower the risk of surfactant towards environmental and human especially.

The researches on surfactant pollution since World War I have shown many emissions of

hannful materials towards environment and gradually risk the health of human. Even though

nonionic surfactant has not been proven 100% safe to environment and human, it has lower

risk of pollution to environment and health degradation of human compared to any other types

of surfactants.

According to Ivankovic & ""enovic (2010), the pollution of surfactants towards

environment contributed to the growth of algae and hazard to the aquatic life. It is also proven

that most portion of surfactants released to the wastewater treatment plants degraded there but

some portion of the surfactants leaching to the surface water, soil or sediment. Thus, as the

demand of environmentally surfactant increase, scientists around the world started to research

about nonionic surfactant that are more environmental friendly compared to the existing ones.

2

j

Therefore, this study is aimed to produce environmental friendly nonionic surfactant from

benzoic acid and palmitic acid.

Benzoic acid is an acid that first discovered by Nostradamus in 16th century from

plants that known as benzoin gum that nowadays can be synthetically produced by using

Grignard reaction. Meanwhile, palmitic acid is fatty acid commonly found in both plants and

animals that is first isolated by Edmond Fremy in 1840. Both chemicals are proven containing

benefits as antifimgal, antioxidant and antiathroscIerotic properties. The objectives of this

study are as follow :

1. To purify benzoic acid prior to synthesizing nonionic surfactant.

2. To synthesis nonionic surfactant from palmitic acid and benzoic acid.

3. To analyze the structure of synthesized nonionic surfactant via FTIR and NMR.

4. To determine the characteristics of the synthesized nonionic surfactant; TLC, cloud

point, wetting time, foam and foam stability, and emulsion stability.

5. To detemrine the percentage yield of the nonionic surfactant synthesized.

3

Literature Review

1.1 Benzoic Acid

Benzoic acid was discovered by Nostradamus in 16th century. Nostradamus in 1556

first described the distillation of gum benzoin. Benzoic acid naturally exists in many plants. It

is fll'St discovered as gum benzoin which is a vegetable resin. In 1560, Alexius Pedemontanus

described about it and followed by Blaise de Vigenere in 1596 (Garcia, 2015).

Its IUPAC name is benzoic acid with several other names which are carboxybenzene,

pbenylethanoic acid and benzenecarboxy1ic acid. Benzoic acid has molecular formula of

C714<h and mass of 122.12 glmol. According to Chambers et al. (2005) and Garcia (2015),

benzoic acid has white crystalline solid shaped of needles. Naturally benzoic acid come from

the tree barks known as gum benzoin however it is also can be made by synthetic mean. In

1832, Justus von Liebig and Friedrich Wohler determined the composition of benzoic acid.

Later in 1875, Salkowski found out about the antifungal activities abilities by benzoic acid.

Figure 2.1 shows the structure of benzoic acid.

o

OH

Figure 2.1 Chemical structure of Benzoic Acid (Garcia, 2015; Maki & Takeda, 2000)

4

Benzoic acid consisted of seven carbon atoms, six hydrogen atoms and two oxygen

atoms. It is an aromatic carboxylic acid with a benzene ring. It commonly used as food

preservatives and precursor for synthesis of other organic substance. It has faint and pleasant

odor. The density of benzoic acid is 1.32 glcm3 in solid with boiling point of 249 DC (480 OF)

and melting point of 122 DC (252 OF) (Maki & Takeda, 2000).

Benzoic acid is soluble in alcohol, ether, benzene, chloroform, acetone, carbon

disulfide, carbon tetrachloride and in fixed and volatile oils. However, it only has slightly

solubility in petroleum ether and hexane. The solubility of benzoic acid in water varies with

temperature (Chambers et al., 2005; Garcia, 2015). Benzoic acid can be synthesized using

Grignard reaction as shown in Figure 2.2 (Solomon & Fryhle, 2011).

oo...... OH

OllgBr

Figure 2.2 The fonnation of benzoic acid (Solomon & Fryhle, 201 I).

5

2.2 Palmitic Acid

Palmitic acid is a commonly found saturated fatty acid in both plants and animals. It

was first isolated in 1840 by Edmond Fremy. It originally is the component of the palm oil.

Later, it was discovered that palmitic acid exists in many food such as butter, cheese and mille

World Health Organization claimed that intake of saturated palmitic acid can increase the risk

of cardiovascular diseases. However, it also containing benefits such as mild antioxidant and

anti-athrosclerotic properties (Legg, 2011).

Palmitic acid is commonly used in the production of soaps, cosmetic and release agent.

Palmitic acid that is originated from palm tree, Elaeis Guineensis sp., will be treated with

sodium hydroxide. This causes hydrolysis process to occur and produce glycerol and sodium

palmitate which widely used in industries. In the making of soap, palmitic acid will be

converted to an alcohol, cetyl alcohol (Legg, 2011).

The IUPAC name of palmitic acid is palmitic acid and also known as hexadecanoic

acid. Palmitic acid also called by the name of palmic acid. It has chemical fonnula of

C'6H32<h and molar mass of 256.43 g/mol. The appearance of palmitic acid is as a white

crystalline powder with the density of 0.85 g/cm3. The boiling point of palmitic acid is 352°C

(666 OF) meanwhile its melting point is 62.9 °c (145.2 OF) (Wirth et ai, 1956). Figure 2.3

shows the structure of palmitic aci almitic acid is very soluble in CH3Cl and soluble in any

acetate and alcohol solutions. The solubility of palmitic acid in water also varies depending on

the temperature.

OH

Figure 2.3 The chemical structure of palmitic acid

6

1.3 Polyethylene Glycol (PEG)

Polyethylene glycol (PEG) is a polyether compound with several other names like

polyoxyethylene (POE) depending on their molecular weight. The PEG that will be used in

this study is PEG 200 with molecular weight of 200 g/mo!. The chemical formula of PEG

C2JLtrt+20rt+1. Historically, PEGs are mostly used in biomedical field . They are oligomers and

polymer with molecular mass lower than 20,000 g/mol. PEG is comes in two forms which are

liquid or low melting point solid. PEGs are synthesized from polymerization of ethylene oxide

ad available with different geometries. The geometries available are as follows:

4 Branched PEGs have 3-10 PEG chains emanating from a central core group.

Star PEGs have 10-100 PEG chains emanating from a central core group.

Comb PEGs have multiple PEG chains normally grafted onto a polymer backbone.

PEG 200 is a clear colorless viscous liquid which soluble in water. It is combustible

with density of 1.125 g/cm3. However, it will not hydrolyze or deteriorate under normal

condition. The chemical structure of PEG 200 is as shown in Figure 2.4. Polyethylene glycol

is usually used in liquid hand soaps, lotions, and creams.

HO~O~O~O~OH

Figure 2.4 Chemical structure of PEG 200.

7

As their application expanding in ranges from chemicals to industrial applications, the

scientists rapidly modified their derivatives to be a suitable use for many uses. The expanding

ranges ofapplications of PEG are resulting from their low cost and useful properties. They are

soluble in aqueous solution and organic solvents and have metal complexing ability. On the

other hand, they are biological compatible and can be easily modified chemically (Harris et ai.,

1984).

Harris et al. (1984) conducted an experiment on producing PEG derivatives and one of

them is synthesis ofPEG-mono palmitate that is derived from PEG and paln:lltic acid. The PEG

used was PEG-6000 which then dissolved in 100 mL toluene. Then, 20 mL of toluene were

removed by distillation to remove water. Palmitic acid was dissolved in 2 mL of 1 M sodium

hydroxide (NaOH) in methanol to form salt. The solvent then removed by lyophylization. The

lyophylate was dissolved in 10 mL anhydrous ethyl ether which was added with 2 mL oxalyl

chloride using dropper. The solvent was removed using rotatory evaporation. The acid

chloride and PEG lastly were mixed together and reflux for 15 min. The mixture later

undergoes cooling process of 4 DC to form the precipitate of products. The yield of PEG­

monopalmitate is 19 g.

8

l.4 Surfactants

Surfactant is short tenn for surface active agent. Surfactants are amphiphilic molecules

that have two different types of part. The tail is hydrophobic (water-hating) usually a long

chain hydrocarbon and the head is hydrophilic (water-loving) usually ionic or strongly polar

groups (Figure 2.5). The word amphiphilic and amphiphile was derived by Paul Winsor 50

years ago. The word came from two Greek roots which are amphi is double, from both sides,

around, as in amphitheater or amphibian meanwhile phi/os is friendship or affinity as in

philanthropist or philosopher (Salaguer, 2002) .

....--.. .. Figure 2.5 Surfactants characteristics (Rosen & Kunjapp'u, 2012)

In the process of cleaning, the surfactant helps to reduce the surface tension so that the

water can be spread and wet the surface. Other function of surfactant are loosening,

emulsifying and holding soil or oil in suspension until it rinsed away (Rosen & Kunjappu,

2012).

9

The surfactant tends to dissolve in aqueous and oil phase. It reduce the surface tension

of water, H20 by adsorbing at the liquid-gas interface and reduce interfacial tension of oil and

water by adsorbing at the liquid-liquid interface.

Surfactant also assembled into aggregates 10 bulk solution. Some are known as

micelles and the concentration of the surfactant started to form micelles is called the critical

micelles concentration or CMC. The micelles can be in many shapes (Figure 2.6). Some are

spherical and some are cylindrical.

Cylindrical M lie Bill

Figure 2.6 Types of micelles of surfactants (Rangel-Yagui et aI. , 2004)

The surfactant is divided into four types which are anionic, cationic, nonionic and

amphoteric surfactant. Anionic surfactant is consisted of negatively-charged head. Cationic is

consisted of positively-charged head. Meanwhile, amphoteric surfactants have dual charged

head which are either positive or negative. Lastly, non ionic surfactant does not have any

charge (Anneken et ai., 2000; Haigh, ~6; Rosen & Kunjappu, 2012). Figure 2.7 shows the

different types of surfactants.

ANIONIC (NEGATIVE)

NONIONIC (NO CHARGE)

CATIONIC (POSITIVE)

AMPHOTERIC (POSITrvE/NEGAnVE)

Figure 2.7 Types ofsurfactants (Rosen & Kunjappu, 2012)

10