PREPARATION OF' SAGO FOR OIL SORPTION of chemically modified sago bark for oil... · PREPARATION...

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PREPARATION OF' SAGO BARK FOR OIL SORPTION Muham'sfd Farid Bin Mohammed Master of (Environmental Science) 2014

Transcript of PREPARATION OF' SAGO FOR OIL SORPTION of chemically modified sago bark for oil... · PREPARATION...

PREPARATION OF' CHE~nCALLY ~10DtFIED SAGO BARK FOR OIL SORPTION

Muham'sfd Farid Bin Mohammed N~lb

Master of Sciellc~ (Environmental Science)

2014

Pusat Khidmat Maklumlt Akadtmil< . I; I1VFR~ MALAYSIA S M'AK

PREPARATION OF CHEMICALLY MODIFIED SAGO BARK FOR OIL SORPTION

MUHAMAD FARID BIN MOHAMMED NOH

A thesis submitted In fulfilment of the requirements for the degree of Master of Science

(Environmental Science)

Faculty of Resource Science and Technology UNIVERSITI MALAYSIA SARA W AK

2014

DECLARATION

I hereby declare that no portion of the work referred to this thesis has been submitted in

support of an application for another degree or qualification to this or any other university

or institution of higher learning.

(MUHA AD FARID BIN MOHAMMED NOH)

Date: 28 ~~~ 2.01tt

...

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LIST OF PUBLICATION

Ngaini, Z., Noh, F., Wahi, R. (2014). Esterified sago waste for engine oil removal in

aqueous environment. Environmental Technology. In Proceeding (Taylor & Francis).

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LIST OF ACHIEVEMENTS

1. Patent: PI 2013002599. Ngaini, Z., Wahi., R., & Noh, M. F. M. (2013). Biodegradable

absorption material and manufacturing method thereof.

2. Noh, M. F. 1\1., Ngaini, Z., & Wahi, R. (2012). Incorporation of fatty acid derivatives

onto sago network for oil absorption, in: ASEAN sago symposium 2012: Advances in

Sago Research and Development, p. 34.

3. Noh, F., Ngaini, Z., & Wahi, R. (2013). Adsorption of spilled oil from seawater by

Metroxylon Sagu bark. 26th Regional Symposium ofMalaysia Analytical Sciences, p.

50.

4. Noh, F., Ngaini, Z., & Wahi, R. (2013). Oil spilled recovery using chemically modified

sago waste. International Festival of Science, Technology, Engineering and

Mathematics.

5. Ngaini, Z., Wahi, R., Noh, M. F. M., & Ahmad, R. R. (2013). Awarded a silver award

for the project entitled "SagoZORB: Solution to Oil Spills" at the UNIMAS Research

and Development Exposition 2013.

6. Ngaini, Z., Wahi, R., Noh, M. F. M., Chuah, L. A., Nourouzi, M. M., & Choong, T. S.

Y. (2014). Awarded a gold award for the project entitled "SagoZORB 2.0: Biomass

Filter Bed for Oil and Grease Removal" at the UNIMAS Research and Development

2014.

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ACKNOWLEDGEMENT

Thank Allah, the Most Merciful Most Gracious for His Guidance and kept me in

His Grace and far from astray, I am finally able to complete this thesis.

The special thank goes to my helpful supervisor, Assoc Prof Dr Zainab Ngaini.

With her enthusiasm, inspiration, and her great efforts to explain things clearly and simply,

she helped to make my research work meaningful for me. The supervision and support that

she gave truly help the progression and smoothness of my thesis. This thesis work was

enabled and sustained by her vision and ideas.

I wish to thank Mdm Rafeah Wahi for her guidance and comments on the

experiments. Her comments and suggestions were very valuable with giving wise advice,

helping with various applications, and so on.

Special appreciation goes to all lab assistant for their endless assistance throughout

my years in UNIMAS.

I would like to acknowledge the support of research grant from CoE­

COESARlPK07/07/2012(Ol) and Ministry of Energy, Green Technology and Water,

Malaysia under Research Fund Mentoring Programs: 1 IPT A 1 Menteri. Special thank also

goes to Kementerian Pengajian Tinggi Malaysia for the financial assistance.

Most importantly, I wish to thank my parents, Muhammed Noh Zainal and Asnah

Abd Kadir for their supports and encouragement throughout my studies in UNIMAS. Their

continuous support and profound understanding very helpful to me for complete this thesis.

Last but not least, thanks to all postgraduate students in organic laboratory. My love

will always be with you guys.

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ABSTRACT

(sago (Metroxylon spp.) bark is a waste material in the sago production industries. The bark

of sago has potential application as a low cost and effective oil sorbent. Raw sago bark

(SB) was esterified using stearic acid to afford modified sago bark (MSB) with greater

hydrophobicity compared to untreated SB. The esterification of SB was conducted by the

addition of stearic acid to the SB with ratio (2:1), in the presence of difference percentage

of catalyst (5, 10, 15 and 20 %) under refluxing ethyl acetat:J In this study, the

esterification of SB using 15 % catalyst afforded MSB with highest oil sorption capacity.

The untreated SB and MSB were characterised by Fourier-Transform Infrared (FTlR)

analysis, Scanning Electron Microscopy (SEM) analysis and Brunauer-Emmett-Teller

(BET) analysis. The physical properties such as proximate analysis, hydrophobicity,

buoyancy, surface area and pore size of untreated SB and MSB were also investigated. The

esterification of SB has successfully increased the buoyancy and hydrophobicity up to 60

%. Sorption study indicated that both untreated SB and MSB were excellent oil adsorbent

in the absence of water. Sorption tests with used engine oil (UEO) were also conducted in

deionized and sea water media in different systems namely wet static system and wet

dynamic system. The MSB afforded higher oil sorption capacity in deionized water up to

2.8 gig in wet static system and 2.5 gig in wet dynamic system compare to untreated SB

(static: 0.12 gig, dynamic: 0.68 gig). In seawater condition, untreated SB showed slightly

higher oil sorption capacity in wet static system (2.0 gig) compare to MSB (1.9 gig). MSB,

however, showed higher oil sorption capacity in wet dynamic system (4.3 gig) at seawater

compared to untreated SB (0.76 gig). The finding indicated on the potential application of

MSB as oil adsorbing material in both deionized and sea water conditions.

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PENYEDlAAN KIMIA KULIT KAYU SAGU YANG TERUBAHSUAI UNTUK PENYERAPAN MINYAK

ABSTRAK

Kulit pokok sagu (Metroxylon spp.) adalah bahan buangan di dalam industri-industri

pengeluaran sagu. Kulit pokok sagu mernpunyai potensi untuk diaplikasi sebagai

penjerapan minyak yang berkos rendah dan efektif. Kulit pokok sagu (SB) diesterkan

menggunakan asid sterik untuk menjadikan kulit sagu terubahsuai (MSB) yang mernpunyai

sifat hidrofobik yang tinggi berbanding SB yang tidak dirawat. Pengesteran SB telah

dijalankan dengan penambahan asid sterik ke SB dengan nisbah (2:1), dalam kehadiran

peratusan pernangkin yang berbeza (5, 10, 15 dan 20 %) di bawah refluks etil asetat.

Dalarn kajian ini, pengesterifikasian SB dengan menggunakan 15 % pernangkin

menghasilkan kapasiti penyerapan minyaknya yang tinggi. SB tidak dirawat dan MSB

dicirikan oleh ana lis is FTIR, analisis SEM dan analisis BET. Ciri-ciri jizikal seperti

analisis proksimat, hidrofobik, keapungan, luas permukaan dan saiz liang juga dikaji.

Proses pengesteran SB berjaya meningkatkan sifat apungan dan hidrofobik sehingga 60

%. Ujian penyerapan minyak dengan menggunakan minyak enjin yang telah digunakan

(UEO) menunjukkan kedua-dua sarnpel mernpunyai kapasiti penyerapan rninyak yang baik

di dalam sistem tanpa kehadiran air. Ujian penyerapan juga dijalankan di dalam sistem

yang mengandungi media air ternyahion dan air laut dengan dua sistem yang berbeza

dinamakan sistem statik lembap dan sistem dinarnik lernbap. MSB menunjukkan kapasiti

penyerapan minyak yang tinggi di dalam air ternyahion sehingga 2.8 gig di dalam sistem

statik lembap dan 2.5 gig di dalam sistern dinarnik lembap berbanding SB tidak dirawat

(statik: 0.12 gig, dinamik: 0.68 gig). Di dalam keadaan air laut, SB tidak dirawat

menunjukkan kapasiti penjerapan minyak yang agak sedikit tinggi di dalan:z sistem statik

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lembap (2.0 gig) berbanding MSB (1.9 gig). Walaubagaimanapun, MSB menunjukkan

kapasiti penjerapan minyak yang tinggi di dalam sistem dinamik lembap (4.3 gig) di air

laut berbanding SB tidak dirawat (0.76 gig). Keputusan yang diperoleh menunjukkan MSB

berpotensi untuk diaplikasi sebagai bahan penjerap minyak di dalam kedua-dua keadaan

air tenyahion dan air laut.

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Pusat Khidmt MakJumlt Akademik UNlVERSffi MALA SIA SARAWAK

TABLE OF CONTENTS

DECLARATION

LIST OF PUBLICATION

LIST OF ACHIVEMENTS

ACKNOWLEDGEMENT

ABSTRACT

ABSTRAK

TABLE OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

LIST OF ABBREVIATIONS

CHAPTER 1

INTRODUCTION

1.1 Research background

1.2 Problem statement

1.3 Justification of study

1.4 Research objectives

1.5 Scope of study

CHAPTER 2

LITERATURE REVIEW

2.1 Nature ofoil and its toxicity

2.2 Oil spills in coastal-marine environment

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I 2.2.1 The causes of oil spills 10

2.2.2 Effect of oil spilts on aquatic ecosystem and human health 11

2.3 Oil removal and recovery technologies 13

2.3.1 Oil removal by sorption techniques 17

2.4 Natural fibrous oil sorbent 19

2.5 Chemical modifications of natural fibres 22

2.6 Metroxylon sagu as potential oil sorbent 24

2.6.1 Sago residues and the potential applications 26

CHAPTER 3

MATERIALS & METHOD

3.1 Materials 29

3.2 Sample preparation 29

3.3 Chemical modification ofSB 30

3.3.1 Pre-treatment of SB 30

3.3.2 Esterification of SB 31

3.4 Characterisation of untreated SB and modified sago bark (MSB) 32

3.4.1 Moisture content 32

3.4.2 Ash content 32

3.4.3 Volatile content 33

3.4.4 Buoyancy and hydrophobicity analysis 34

3.4.5 Measurement of BET surface area and pore volume 35

3.4.6 Fourier-Transform Infrared (FTIR) analysis 35

3.4.7 Scanning electron microscopy (SEM) and elemental compositions

analysis 36

x

,....

3.5 Sorption experiments procedure 36

3.5.1 Water uptake 36

3.5.2 Oil sorption capacity 37

3.6 Reusability test of untreated SB and MSB 38

CHAPTER 4

RESUL TS & DISCUSSION

4.1 Esterification of sago bark (SB) 40

4.1.1 Pre-treatment of SB using NaOH 41

4.1.2 Esterification of SB using CaO 42

4.2 Chemical and physical properties of untreated SB and MSB 45

4.3 Water uptake study of untreated SB and MSB 48

4.3.1 Water uptake in the static system 48

4.3.2 Water uptake in the dynamic system 49

4.4 Oil sorption capacity of untreated SB and MSB 51

4.4.1 Oil sorption capacity in the wet static system 51

4.4.2 Oil sorption capacity in the wet dynamic system 55

4.4.3 Oil sorption capacity in the dry system 58

4.5 The effect of reusability 60

4.6 Comparison with other natural sorbents for removal of oil 61

CHAPTERS

CONCLUSION & RECOMMENDATION

5.1 Conclusion 63

5.2 Recommendation 65

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REFERENCES

APPENDIX A

APPENDIXB

APPENDIXC

APPENDIXD

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Table 2.1

Table 2.2

Table 2.3

Table 2.4

Table 2.5

Table 4.1

Table 4.2

Table 4.3

LIST OF TABLES

Page

Some major oil spill cases around the world and the 8 corresponding effects and clean-up techniques

Oil spill incidents in Malaysia 9

Composition of the Prestige fuel oil and toxicity of its 12 components

Methods for oil spill clean-up based on previous 14 study

The composition of sago hampas 28

Yield of MSB obtained under different percentage of 43 catalyst and response

Chemical and physical characteristics of untreated SB 46 andMSB

Studied natural sorbents for removal of oil 62

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,... I

Figure 2.1

Figure 2.2

Figure 2.3

Figure 2.4

Figure 2.5

Figure 3.1

Figure 3.2

Figure 4.1

Figure 4.2

Figure 4.3

Figure 4.4

Figure 4.5

Figure 4.6

Figure 4.7

Figure 4.8

Figure 4.9

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LIST OF FIGURES

Millions gallons of spilled oil in marine environment from different sources

Proposed mechanism of adsorption

Sago palms in Pusa, Sarawak

Production of sago starch

The abundance production of (a) sago bark, (b) sago hampas and wastewater after starch extraction process

Preparation of (a) raw SB after debarking process, (b) shredded SB, and (c) ground SB

Different sorption systems in (a) dry system (b) wet static system and (c) wet dynamic system (on orbital shaker)

FTIR spectra of (a) untreated SB, (b) pre-treated SB with NaOH and (c) esterified pre-treated SB

FTIR spectrum ofMSB (sample 4)

SEM micrographs of (a) untreated SB and (b) MSB before oil adsorption

The buoyancy of (a) untreated SB and (b) MSB in water system

Water uptake of untreated SB and MSB in static system: (a) deionized water, and (b) seawater

Water uptake of untreated SB and MSB in dynamic system: (a) deionized water, and (b) seawater

Sorption capacity of untreated SB and MSB in the mixture of oil and water static system: (a) deionized water, and (b) seawater medium

The evaluation of oil sorption capacity for untreated SB and MSB in static system: (a) deionized water, and (b) seawater medium

20 x 20 cm sorbent kit consisted of untreated SB or MSB

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Figure 4.1 0 The process of clean-up UEO in deionized water: (a) 55 sorption after an hour, and (b) sorption after 24 h

Figure 4.11 Sorption capacity of untreated SB and MSB in the 56 mixture of oil and water dynamic system: (a) deionized water, and (b) seawater medium

Figure 4.12 The evaluation of oil sorption capacity for untreated 57 SB and MSB in dynamic system: (a) deionized water, and (b) seawater medium

Figure 4.13 Oil sorption capacity of untreated SB and MSB in the 59 dry system

Figure 4.14 SEM micrographs of (a) untreated SB and (b) MSB 59 after oil adsorption from UEO

Figure 4.15 Reusability and oil sorption capacity of untreated SB 60 and MSB

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LIST OF ABBREVIATIONS

SB Sago Bark

MSB Modified sago bark

UEO Used engine oil

ASTM American Society for Testing Materials

FTIR Fourier Transfonn Infrared

SEM Scanning electron microscopy

EDX Electron dispersive X-ray

BET Brunauer-emmett-teller

PAH Polycyclic aromatic hydrocarbon

NBS N-bromosuccinimide

WPG Weight per cent gain

S.D Standard deviation

K Kelvin

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CHAPTERl

INTRODUCTION

1.1 Research background

Water pollution caused by oil spills has been receiving a great attention due to its adverse

environmental effects. Approximately 224,000 tonnes of oil spilled reported in marine

environment globally between 2000 and 2011 (ITOPF, 2011). Oil pollution occurs due to

tanker disaster, wars, operation failure, accidents, and natural disaster during the operation,

transportation and storage of oil (Rengasamy et ai., 2011). Domestic and industrial activities

have also contributed significantly to oil pollution in environment.

Oil pollution has given both immediate and long-term environmental damages. Oil spills have

damaged the beaches, marshlands and marine ecosystem (Annunciado et ai., 2005). It also

gives negative impact to marine mammals, birds and fish, and destroyed wildlife habitat and

breeding grounds. The oil not only severely pollutes the marine environment, but also poses a

serious threat to marine life (Wang et ai., 2010). The formation of oil-in-water emulsion or

floating film occurs during oil spill could be toxic to ~icroorganisms for oil biodegradation

process (Karan et ai., 2011).

Due to the serious oil pollution problems in water bodies, many oil removal technologies have

been introduced and improved. The aims are to return the functions of an ecosystem and re­

establish the biological community in the ecosystem (Karana et ai., 2011). Examples of

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available oil removal techniques are in-situ burning, bioremediation, mechanical methods,

chemical methods, and sorbents. However, these techniques are not available for all types of

spilled oil. There are some factors that might affect oil spilled control such as type of oils, the

surface on which it spills, the soil and subsoil conditions, and the weather conditions (AI­

Majed et ai., 2012).

Adsorption using appropriate oil sorbent seems to be the best solution for oil spill recovery

due to its effectiveness, feasibility, simplicity and easy handling (Wahi et ai., 2013). A good

sorbent usually possess high oleophilic and hydrophobic property (Deschamps et al., 2003),

high oil sorption capacity, buoyancy and retention over time, durability in aqueous media,

reusability and biodegradability (Karana et aI., 2011), environmental friendly, and low-cost

method (Shavandi et al., 2012). There are three classes of oil sorbents which are commonly

reported. It includes synthetic organic, inorganic mineral and agricultural (organic) products

(Deschamps et aI., 2003; Radetic et al., 2008; Sun et al., 2003; Wahi et aI., 2013). The most

often reported on synthetic organic sorbents are polyurethane (Li et al., 2012) and

polypropylene (Lin et aI., 2010). The example of inorganic sorbents are organoclay (Cannody

et al., 2007), calcium carbonate (Arbatan et al., 2011). Kapok (Abdullah et aI., 2010; Lim and

Huang, 2007), vegetable fibres (Annunciado et al., 2005), sawdust (Banerjee et al., 2006),

cotton fibres (Deschamps et al., 2003), rice husks (Kumagai et al., 2007), populus seed fibres

(Likon et al., 2013), and sugar cane bagasse (Said et aI., 2009; Sun et al., 2003; Hussein et al.,

2008) are the examples of natural organic sorbents. Natural organic sorbents are the best oil

sorbents material in tenns of abundance, eco-friendly, comparatively low cost, sustainable and

biodegradable compared to other sorbents.

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Despite of their advantages, many natural sorbents might be submerged after saturation due to

its ability to absorb/adsorb both oil and water (Li et ai., 2012). Lack of hydrophobicity and

low buoyancy of the sorbent will reduce the effectiveness of oil sorption in aqueous system.

Therefore, several approaches have been made to improve oil sorption capacity of natural

sorbent material through chemical modification. Among the approaches are solvent treatment

(Wang et ai., 2012, Abdullah et ai., 2010), esterification (Banerjee et ai., 2006; Said et ai.,

2009), and acetylation (Adebajo and Frost, 2004; Sun et ai., 2003; Sun et ai., 2004).

Sago bark, a type of waste from metroxyion sagu, has potential to be used as natural fibre for

oil removal. It is because sago bark comprises of cellulose and lignin with large amount of

hydroxyl functional groups (-OH), which prone to chemical modification and used for oil

sorption. Metroxyion sagu also known as sago comes from genus metroxyion and belongs to

Palmae family (Singhal et ai., 2008). In the production of sago starch, large quantity of waste

which contains both solid and liquid materials is produced. In Sarawak, about 20,000 tons of

sago barks were produced annually from sago mill industries (Wahi et ai., 2014). Most people

use the barks of the trunk as timber fuel, temporary walls, ceilings and fences (Rahman, 2008).

Due to its chemical composition, raw sago bark has the potential to be utilised as oil sorbent.

The raw sago bark generally has good sorption capacity, comparable density with synthetic

sorbent, chemical free and highly degradable. Therefore, the utilisation of agricultural waste

such as sago bark into value added products is good to be used for global environmental

conservation and sustainable development (Rahman and Sundin, 2008).

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1.2 Problem statement

In Malaysia, oil pollution is one of the mam prob~ems affecting the marine coastal

environment. Oil pollution in coastal area occurs from t!xploitation, extraction, transportation

and/or disposal activities (Rengasamy et aI., 2011). Oil spills are serious environmental

disasters, often leading to significant, long-term impacts on the environment, ecology and

sosio-economic activities of an area. Mortality and damage to marine life, disrupting the food

chain, affecting community health and many others are examples of oil spill effects. Safe and

environmentally oil spill management has become an increasing problem worldwide. Thus, oil

spills should be handled systematically and effectively to reduce environmental pollution

especially in lake, river and marine environment. Most published works on the oil spill

remediation has dealt with advanced recovery technology. Wahi et al. (2013) claimed that

removal ofoil particles in oily water by advanced technologies have certain limitations such as

expensive and difficult to maintain. Biomass such as agricultural wastes is the most potential

natural resource of oil spill remediation. Sago starch production industry generated significant

amount of wastes sago bark annually, which is about 20,000 tons (Wahi et aI., 2014). The high

production of sago bark in sago processing industries could be the alternative way to recovery

oil spill. However, the major drawbacks of this waste are low hydrophobicity and low

buoyancy that could lead to low oil removal efficiency and low oil sorption capacity. One of

the chemical modification techniques to increase oil removal efficiency of natural sorbent is

esterification. Modification of natural sorbent via esterification has been proven to contain

lower water uptake and higher oil sorption capacity in comparison with untreated fibre

(Banerjee et aI., 2006; Said et al., 2009). This study has directed on improving and deploying

natural sorbent which are not only low cost but also safest resources of oil spill control.

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1.3 Justification of study

The present research examines a chemical modification of sago bark using esterification with

fatty acid derivative for the preparation of oil sorption materials. So far, only few studies on

esterification of natural fibre for oil sorption were conducted and no studies on esterification

of sago bark have been published. Therefore, this study provides information regarding the

usefulness of modified sago bark via esterification with fatty acid derivative for oil spilled

treatment in water bodies. This study also provides information on the characteristic of

untreated sago bark and modified sago bark as oil sorbents. The modification of sago bark

could be used effectively to recover oil spilled in water bodies for instance, heavy industrial

wastewater or ecosystem.

1.4 Research objectives

The objectives of this study are:

1. To prepare the modified sago bark (MSB) via esterification with fatty acid

derivative for oil sorption.

11. To characterise the untreated sago bark (SB) and MSB as oil sorbent that are

applicable to clean up oil spill.

111. To investigate and compare the capability of untreated SB and MSB to adsorb used

engine oil (UEO) in deionized water and seawater system

IV. To study the reusability of untreated SB and MSB.

5

I.S Scope of study

In this study, modification of SB with stearic acid and calcium oxide as a catalyst was

perfonned via esterification process. The scope of this study involved measuring the

behaviours of untreated SB and MSB as oil sorbent. The untreated SB and MSB were

characterised by proximate analysis, FTIR analysis and SEM analysis. The physical properties

such as hydrophobicity, buoyancy, surface area and pore size of untreated SB and MSB were

also investigated. In tenns of application, untreated SB and MSB were exposed in oily water

containing UEO. Oil sorption in water system was studied in non-turbulent (wet static system)

and turbulent (wet dynamic system) environment. In addition, oil sorption behaviour of

untreated SB and MSB in oily seawater were also examined. Water sorption capacity was

perfonned to evaluate the potential of untreated SB and MSB to adsorb water. The reusability

test of MSB was conducted and the results were compared to the untreated SB.

6

CHAPTER 2

LITERATURE REVIEW

2.1 Nature of oil and its toxicity

Oil is a complex substance containing hundreds of different compounds mainly consist of

carbon and hydrogen which is immiscible with water but soluble in organic solvents. There

are many different types of oil ranging from very light oils to heavy crude oils depending on

the number of carbon atoms in the hydrocarbon chain (Boyd et al., 2001 ). It includes 284

crude oils varying in proportion, and refined oils such as diesel oil, heavy fuel oil, lubricating

oil, kerosene and gasoline (Enache and Zagan, 2009). Oil is a viscous liquid having density

less than water. In addition, oil is immiscible in water thus emulsion will form between oil and

water or floating film that can caused water pollution (Karan et al., 2011).

Water pollution caused by oil spillage is very dangerous to ecosystem due to its toxicity.

Different oil types have different toxicity and can be divided into different groups based on the

properties of spilled oil. Enache and Zagan (2009) stated there are three main groups of oil

which are light refined, heavy refined and crude oils. !hey can be distinguished according to

their appearance on the water surface. Light refined oils such as petrol, gasoline and kerosene

are very volatile and will evaporate quickly after spill, often disappear within two to three

days. Heavy refined oils such as diesel and fuel oil are very viscous and do not disappear

naturally. Characteristics and behaviours of crude oils can be classified according to their

types and origins. Most crude oils will form emulsion with seawater within 24 to 48 h. This

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