BIODIESEL FROM WASTE PALM OIL AND CHICKEN FATS AS A … from waste palm oil and chicken... · penggunaan bahan api fosil. Dari sudut pandangan alam sekitar dan aspek ekonomi, bahan

Faculty of Engineering

BIODIESEL FROM WASTE PALM OIL AND CHICKEN FATS

AS A GREEN FUEL FOR DIESEL ENGINE

Jong Yang

Master of Engineering

(Mechanical and Manufacturing Engineering)

2012

BIODIESEL FROM WASTE PALM OIL AND CHICKEN FATS

AS A GREEN FUEL FOR DIESEL ENGINE

Jong Yang

Thesis submitted to the Faculty of Engineering, University Malaysia Sarawak, in

fulfillment of the requirement for the degree of Master in Mechanical and Manufacturing

Enginneering

Faculty of Engineering

UNIVERSITY MALAYSIA SARAWAK

2012

AUTHOR‟S DECLARATION

I hereby declare that this thesis is my original writing. This is a true copy of the

thesis, including any required final revisions, as accepted by my examiners.

I understand that my thesis may be made electronically available to the public.

____________________ ____________________

Jong Yang Dr. Abu Saleh Ahmed

Student No. 10021587 (Supervisor)

ACKNOWLEDGEMENTS

I would like to express my gratitude and appreciation to my supervisor Dr. Abu

Saleh Ahmed, Mechanical & Manufacturing Engineering Department in Faculty of

Engineering at University Malaysia Sarawak, for his support, guidance and constructive

comments to enhance the quality of this thesis. I am so grateful to my co-supervisor Dr.

Sinin Hamdan for his valuable suggestions as a guardian. Thanks to some of the post

graduate students‟ for their inspiration.

My thanks also to the technicians of Mechanical & Manufacturing Engineering

Department, Chemical Engineering & Energy Sustainability Department in Faculty of

Engineering and Faculty of Resource Science & Technology at University Malaysia

Sarawak, who helped me in laboratory during research work. I would like to show my

appreciation to all have provided assistance to me in pursuing my Master of Engineering

(Mechanical & Manufacturing) Degree in Faculty of Engineering, UNIMAS.

I also like to acknowledge the financial support of Skim Yayasan Biasiswa

Sarawak Tunku Abdul Rahman during my research work.

Special thanks to my beloved family members for their support.

ABSTRAK

Pembangunan sektor perindustrian dan peningkatan populasi menyebabkan

permintaan tenaga dunia meningkat dengan berterusan. Bahan api fosil adalah terhad

kerana pembentukannya mengambil masa berjuta-juta tahun. Kesediaannya mungkin

boleh dipanjangkan dengan mengurangkan penggunnaannya. Oleh itu, beberapa negara

menggunakan pelbagai sumber tenaga yang boleh diperbaharui untuk mengurangkan

penggunaan bahan api fosil. Dari sudut pandangan alam sekitar dan aspek ekonomi, bahan

api diperolehi daripada lemak dan minyak sebagai alternatif untuk menggantikan bahan

api berasaskan petroleum telah menarik perhatian yang besar di seluruh dunia.

Biodiesel, metil ester asid lemak merupakan tenaga yang terbiodigradasikan, boleh

diperbaharui dan mampan. Ia dihasilkan daripada minyak tumbuhan atau lemak haiwan

melalui proses pengtransesteran bersama alkohol berantai pendek atau melalui proses

pengesteran asid lemak. Proses pengtransesteran merangkumi transformasi trigliserida

kepada metil ester asid lemak, dengan kehadiran alkohol dan mangkin, di mana gliserol

sebagai produk sampingan. Sisa minyak dan lemak merupakan salah satu bahan mentah

penghasilan biodiesel yang memberangsangkan kerana ketersediaannya dan kos bahan

yang murah berbanding dengan bahan mentah yang lain. Tambahan pula, penggunnaa sisa

minyak dan lemak untuk menghasilkan biodiesel juga membantu mengurangkan masalah

pelupusan yang boleh membawa kesan buruk terhadap alam sekitar.

Penyelidikan ini dijalankan untuk mengkaji pertukaran sisa minyak dan lemak

kepada biodiesel, prestasi enjin diesel dan menganalisis kandungan pelepasan ekzos dari

enjin diesel yang menggunakan campuran biodiesel. Sisa minyak masak yang terkumpul

menjalani bes pengtasesterifikasi selepas proses prarawatan kerana nilai asidnya kurang

daripada 4. Lemak ayam yang diekstrak mempunyai nilai asid yang melebihi 4 (5.23) pula

menjalani pengesteran asid untuk menukar asid lemak bebas kepada metil ester asid lemak

sebelum pengtransesteran dijalankan. Peratusan penukaran lemak ayam kepada biodiesel

asalah lebih tinggi berbanding dengan peratus penukaran dari sisa minyak. Hasil tertinggi

didapati 96% pada nisbah minyak kepada methanol 1:4 dan 0.5 wt% kalium hidroksida.

Campuran biodiesel dengan diesel petroleum antara B0 (100% diesel petroleum)

kepada B50 (50% biodiesel + 50% petroleum diesel) telah disediakan untuk menjalani

ujian prestasi enjin. Keputusan menunjukkan kuasa brek dan penggunaan bahan api tentu

meningkat apabila peratusan biodiesel bertambah dalam campuran bahan api. Biodiesel

mempunyai kuasa output enjin yang kurang berbanding dengan diesel petroleum dan ia

berkurang apabila peratusan biodiesel dalam capuran bahan api bertambah. Analisis

pelepasan ekzos menunjukkan bahawa campuran biodiesel mempunyai pelepasan karbon

monoksida (CO), nitrogen oksida (NOx) dan hidrokarbon (HC) yang berkurang

berbanding dengan diesel petroleum.

ABSTRACT

The increases in industrialization and population have caused the world energy

demand to increase continuously. As the fossil fuels are limited and it takes millions of

years for their formation, their availability may be prolonged by decreasing overall

consumption. Thus, various renewable sources of energy have successfully been tried and

used by different countries to reduce the use of fossil fuels. Fuels derived from fats and

oils as alternative to replace petroleum-based diesel fuel have attracted huge attention over

the world due to its environmental and economic benefits.

Biodiesel, fatty acid methyl ester (FAME) is a biodegradable, renewable and

sustainable energy. It is derived from vegetable oil or animal fats through

transesterification process with short chain alcohols or by the esterification of fatty acids.

The transesterification reaction consists of transforming triglycerides into FAMEs, in the

presence of an alcohol and a catalyst, with glycerol as a by-product. Waste oil and fats

have emerged as one of the most promising feedstock for biodiesel production due to its

availability and inexpensive price as compared to other sources of biodiesel production. In

addition, the usage of waste oil and fats for biodiesel production also helps in reducing the

disposal problems which give adverse effect to the environment.

This research was conducted to study the conversion of waste oil and fats into

biodiesel, engine performance and exhaust emission analysis of diesel engine using the

wastage biodiesel blends. Collected waste cooking oil was undergoing base

transesterification after pretreatment process since its acid value was lower than 4. The

extracted chicken fats with acid value more than 4 (5.23), had undergone acid

esterification and converted free fatty acids into FAME before transesterification. The

conversion of biodiesel from chicken fats was higher than that of waste cooking oil. The

highest yield was found to be 96% at oil-to-methanol ratio of 1:4 and 0.5 wt% of

potassium hydroxide (KOH).

Biodiesel blends with petroleum diesel ranging from B0 (100% petroleum diesel)

to B50 (50% v/v biodiesel + 50% v/v petroleum diesel) were prepared to carry out the

diesel engine performance test. The results showed the brake power and specific fuel

consumption (SFC) were increased as biodiesel percentages increased in fuel blends. The

engine power output of biodiesel blends were lower than petroleum diesel and decreased

as biodiesel percentage increased in fuel blends. The exhaust emission tests showed that

biodiesel blends had a slightly lower emission of carbon monoxide (CO), nitrogen oxide

(NOx) and hydrocarbon (HC) than petroleum diesel.

TABLE OF CONTENTS

Content Page

ACKNOWLEDGEMENTS i

ABSTRAK ii

ABSTRACT iv

LIST OF TABLES x

LIST OF FIGURES xii

LIST OF ABBREVIATIONS xv

CHAPTER 1: INTRODUCTION

1.1 Background 1

1.2 Advantages of Biodiesel 3

1.3 Biodiesel from Wastage 6

1.3.1 Potential of Wastage Biodiesel 7

1.3.2 Global Status of Wastage Biodiesel 9

1.4 Biodiesel in Malaysia 11

1.4.1 Biodiesel in Sarawak 13

1.5 Problem Statement 13

1.6 Objectives 14

1.7 Brief Outline of the Report 15

CHAPTER 2: LITERATURE REVIEW

2.1 Introduction 16

2.2 Biodiesel in Worldwide 17

2.2.1 Biodiesel in European Union (EU) 19

2.2.2 Biodiesel in United States 20

2.3 Biodiesel in Asian 21

2.3.1 Biodiesel in (the) People‟s Republic of China 24

2.3.2 Biodiesel in India 25

2.3.3 Biodiesel in Indonesia 26

2.3.4 Biodiesel in Philippines 27

2.3.5 Biodiesel in Thailand 28

2.3.6 Biodiesel in Others Asian Country 30

2.3.7 Impacts of Biodiesel Production in Asia 30

2.4 Biodiesel Production 35

2.4.1 Biodiesel Feedstock/Raw Materials 36

2.4.2 Biodiesel Conversion 43

2.4.2.1 Pyrolysis 44

2.4.2.2 Dilution 44

2.4.2.3 Microemulsion 45

2.4.2.4 Transesterification 45

2.5 Variables Affecting the Transesterification Reaction 58

2.5.1 Free Fatty Acids 58

2.5.2 Water Content 59

2.5.3 Alcohol and Molar Ratio Employed 60

2.5.4 Types and Amount of Catalyst 62

2.5.5 Reaction Temperature 64

2.5.6 Rate and Mode of Stirring 64

2.5.7 Purification of the Final Product 65

2.6 Properties of Oils/Fats and Biodiesel 66

2.6.1 Properties of Oil/Fats 66

2.6.2 Properties of Biodiesel 69

2.7 Uses of Biodiesel and Their Performance 74

2.8 Exhaust Emissions 80

2.9 Problems Arise During the Use of Biodiesel 87

CHAPTER 3: METHODOLOGY

3.1 Introduction 89

3.2 Experimental Site 90

3.3 Feedstock Collection 94

3.4 Chicken Fat Extraction 95

3.4.1 Pretreatment of Used Cooking Oil 95

3.4.2 Acid Value Determination 97

3.5 Biodiesel Production 98

3.5.1 Acid Esterification 99

3.5.2 Transesterification 101

3.5.3 Biodiesel Settling 102

3.5.4 Separation of Biodiesel 102

3.5.5 Purification 103

3.6 Biodiesel Test 104

3.6.1 Blending of Biodiesel 104

3.6.2 Engine Performance Test 105

3.6.3 Emission Test 106

3.6.4 Fourier Transform Infrared Spectroscopy 108

CHAPTER 4: RESULTS AND DISCUSSION

4.1 Introduction 109

4.2 Acid Value Determination 109

4.3 Acid Estrification 110

4.4 Transesterification 111

4.4.1 Methanol/Oil Ratio 111

4.4.2 Amount of Catalyst 113

4.5 Characteristics Result 118

4.5.1 Infrared Spectroscopy 118

4.5.2 Physical Properties of Biodiesel 123

4.6 Engine Performance 124

4.6.1 Brake Power 124

4.6.2 Specific Fuel Consumption 126

4.6.3 Engine Power Output 129

4.7 Emission Test 132

CHAPTER 5: CONCLUSION AND RECOMMENDATION

5.1 Conclusion 136

5.2 Recommendation 138

REFERENCES 141

PUBLICATIONS 170

APENDIX-A 171

APENDIX-B 172

LIST OF TABLES

Table Page

Table 2.1: Bio-fuels Policies in Selected Asian Countries. 22

Table 2.2: Top 10 Countries in terms of Absolute Biodiesel Potential. 35

Table 2.3: Sources of Oil. 40

Table 2.4: Tansesterification Method. 52

Table 2.5: Enzymatic Transesterification Reaction Using Various Types of Alcohols

and Lipase

54

Table 2.6: Comparison of the Advantages and Disadvantages between Various

transesterification Methods

57

Table 2.7: Level of FFA Recommended for Alkaline Transesterification. 59

Table 2.8: Chemical Structure of Common Fatty Acids 67

Table 2.9: Oils Characteristic 69

Table 2.10: Physical Properties of Biodiesel 71

Table 2.11: Comparison of Fuel Properties of Petroleum Diesel and Biodiesel 72

Table 2.12: Chemical Structure of Oil, Ester and Petroleum Diesel 73

Table 2.13: Performance of Biodiesel Fuelled Engine as Compared to Diesel Fuelled

Engine

75

Table 2.14: Comparative of Exhaust Emission for Biodiesel or its Blends Relative to

Petroleum Diesel

84

Table 3.1: Specification of Chemicals. 93

Table 3.2: Diesel Engine Specification 106

Table 3.3: Test Sequence and Fuel Composition 107

Table 4.1: Results of Acid Numbers Determination by Titration. 110

Table 4.2: Comparison of Acid Value Before and After Acid Esterification. 111

Table 4.3: Comparison of Physical Properties of Biodiesels and Diesel. 123

LIST OF FIGURES

Figure Page

Figure 2.1: World‟s Biodiesel Production, 2009. 18

Figure 2.2: Worldwide Production of Biodiesel, 2001-2009. 18

Figure 2.3: World Biodiesel Consumption, 2001-2009. 19

Figure 2.4: Mechanism of Thermal Decomposition of Triglycerides. 44

Figure 2.5: Transesterification of Triglycerides 46

Figure 2.6: Transesterification Reaction 47

Figure 2.7: Mechanism of the Alkali-Catalyst Transesterification of Vegetable

Oils

48

Figure 2.8: Mechanism of Acid Catalyzed Transesterification 49

Figure 2.9: Flow Diagrams Comparing Biodiesel Production using Lipase-

Catalyst

50

Figure 2.10: Chemical Structure of Vegetable Oil. 66

Figure 2.11: Percent Change in Exhaust Emission vs Biodiesel Percentage in

Blend

81

Figure 2.12: Fuel-cycle CO2 Emission for Petroleum Diesel, B20 and B100 82

Figure 3.1: Overview of Methodology 89

Figure 3.2: Waste cooking Oils 94

Figure 3.3: Collected Chicken by-Product 95

Figure 3.4: Soxhlet Extraction 96

Figure 3.5: Filtrating Waste Cooking Oil 96

Figure 3.6: Titration Setup and the End-Point for the Titration of Oil. 98

Figure 3.7: Schematic Diagram of Biodiesel Production Process 99

Figure 3.8: Acid Exterification 100

Figure 3.9: Acid Esterification Setup. 101

Figure 3.10: The Mixture Formed Two Layers After Settled Over Night. 102

Figure 3.11: Washing Process of Impure Biodiesel. 103

Figure 3.12: Infrared Spectrophotometer 108

Figure 4.1: Effect of Methanol-to-Oil Ratio on the Production Yield 112

Figure 4.2: Effect of Catalyst Percentages on the Biodiesel Production Yield from

Waste Cooking Oil

113

Figure 4.3: Effect of Catalyst Percentages on Biodiesel Production Yield From

Chicken Fats.

115

Figure 4.4: Biodiesel Production Yield From Waste Cooking Oil Using KOH. 115

Figure 4.5: Biodiesel Production From Waste Cooking Oil Using NaOH. 116

Figure 4.6: Biodiesel Production From Chicken Fats Using KOH. 117

Figure 4.7: Biodiesel Production From Chicken Fats Using NaOH. 117

Figure 4.8: FTIR Spectrum of Petroleum Diesel. 115

Figure 4.9: FTIR Spectrum of WCO and WOB. 116

Figure 4.10: FTIR Spectrum of Chicken fat and WFB. 117

Figure 4.11: Brake Power (kW) vs. Engine Speed (rpm) Obtained During

Performance Tests Using WOB Blends.

124

Figure 4.12: Brake Power (kW) vs. Engine Speed (rpm) Obtained During

Performance Tests Using WFB Blends.

125

Figure 4.13: Specific Fuel Consumption of Various WOB Blends 127

Figure 4.14: Specific Fuel Consumption of Various WFB Blends. 127

Figure 4.15: Comparison of Specific Fuel Consumption of Biodiesel Blends

Between WOB

128

Figure 4.16: Engine Power Output of Various WOB Blends. 129

Figure 4.17: Engine Power Output of Various WFB Blends. 130

Figure 4.18: Comparison of Engine Power Output of Biodiesel Blends Between

WOB and WFB.

131

Figure 4.19: CO Emission vs. Engine Speed. 132

Figure 4.20: NOx Emission (ppm) vs. Engine Speed (rpm) 134

Figure 4.21: HC Emission (ppm) vs. Engine Speed (rpm). 135

LIST OF ABBREVIATIONS

ASTM - American Society for Testing and Materials

B100 - 100% biodiesel

B20 - 20% biodiesel + 80% Petroleum Diesel

Bgy - Billion Gallons per Year

C=C - Alkenes Functional Group

C=O - Carbonyl Functional Group

C–H - Alkanes Fuctional Group

CH3ONa - Sodium Methoxide

CH4 - Methane

CO - Carbon Monoxide

CO2 - Carbon Dioxide

EU - European Union

FAME - Fatty Acid Methyl Ester

FFA - Free Fatty Acid

FTIR - Fourier Transform Infrared Spectroscopy

GHG - Greenhouse Gaseous

H2SO4 - Sulphuric Acid

HC - Hydrocarbon

HPLC - High Pressure Liquid Chromatography

IEA - International Energy Agency

KOH - Potassium Hydroxide

MeOH - Methanol

mg - miligram

NaOH - Sodium Hydroxide

NOx - Nitrogen Oxides

O–H - Hydroxyl Functional Group

OPEC - Organization of the Petroleum Exporting Countries

PM - Particulate Matter

PRC - People Republic China

SFC - Specific Fuel Consumption

SO2 - Sulphur Oxides

VOC - Volatile Organic Compound

WCO - Waste Cooking Oil

WFB - Waste Fat Biodiesel

WOB - Waste Oil Biodiesel

CHAPTER 1

INTRODUCTION

1.1 Background

The increase in industrialization and population has caused the world energy

demand to increase continuously. Total world energy usage is predicted to rise from 495

quadrillion Btu in 2007, to 590 quadrillion Btu in 2020 and 739 quadrillion Btu in 2035

(US Energy Information Administration, 2010a). The World Energy forum has predicted

that fossil-based oil, coal and gas reserves will be exhausted in less than 10 decades. As

the fossil fuels are limited and it takes millions of years for their formation, their

availability may be prolonged by decreasing its overall consumption. In addition, world

crude oil price increased from USD 34.57 per barrel in January 2009 to USD 111.42 per

barrel in April 2011 and the oil price are expected to be increasing continuously (US

Energy Information Administration, 2010b). Oil prices have been especially sensitive to

demand expectations, with producers, consumers, and traders continually looking for an

indication of possible recovery in world economic growth and a likely corresponding

increase in oil demand. Thus, various renewable sources of energy have successfully been

tried and used by different countries to reduce the use of fossil fuels. These renewable

sources of energy include solar energy, wind energy, geothermal energy, tidal energy,

ocean thermal energy, hydropower and others. (Gui et al., 2008). Among all these

resources, fuels derived from fats and oils as alternative to replace petroleum-based diesel

fuel has attracted huge attention over the world due to its environmental and economic

benefits.

Rudolf Diesel invented diesel engine in 1892 and received the patent in 1983 (Shay,

1993). Diesel engines are main workhorses for heavy-duty vehicles because of their good

fuel economy and durability. They have higher thermal efficiency, resulting from high

compression ratio and lean fuel combustion. On 10 August 1893, he ran his own diesel

model with peanut oil for the first time in Augsburg, Germany. In 1930s and 1940s,

vegetables oils were used as diesel fuels when petroleum supplies were expensive. During

World War II, Belgium, France, Italy, UK, Portugal, Germany, Brazil, Argentina, Japan

and China were using vegetable oils as emergency fuels (Goering et al., 1982). Vegetable

oil has almost similar energy density, cetane number, heat of vaporization, and

stoichiometric air/fuel ratio with petroleum diesel. However, vegetable oils cannot be used

directly in diesel engines as the high viscosity of vegetable oils if compared to petroleum

diesel fuel results in poor atomization. Thus, applying vegetable oils to diesel engine will

cause injector coking, severe engine deposits, filter gumming problems, piston ring

sticking and thickening of the lubricant oil (Murugesan et al., 2009).

On 31 August 1937, G. Chavanne, a Belgian academician at the University of

Brussels, obtained a patent, entitled “Procedure for the transformation of vegetable oils for

their uses as fuels” – Belgian patent 422,877. This patent described the alcoholysis of

vegetable oils using alcohol. Alcoholysis also called transesterification which separate the

fatty acids from the glycerol by replacing the glycerol with short linear alcohols. This is

the first production of biodiesel although transesterification of vegetable oils was

conducted in 1853, before diesel engine became functional (Werner, 2003).

Transesterification is an organic reaction where an ester is transformed into another

through interchange of the alkoxy moiety (Ramadhas et al., 2005). When the ester is

reacting with an alcohol, the tranesterification process is called alcoholysis. In the

transesterification of vegetable oils, a triglyceride reacts with an alcohol in the presence of

a strong acid or base, producing a mixture of fatty acids alkyl esters and glycerol. The

overall process is a sequence of three consecutive and reversible reactions, in which di-

and monoglycerides are formed as intermediates. The fatty acid alkyl esters that is

produced from this process is called biodiesel.

1.2 Advantages of Biodiesel

According to Oil and Gas Journal (O&GJ) estimate, worldwide reserves at the

beginning of 2004 were 1.27 trillion barrels of oil and 6,100 trillion cubic feet of natural

gas. These are roven recoverable reserves. In today‟s consumption rate, about 85 barrels

per day of oil and 260 billion cubic feet per day of natural gas, the reserves will end in

2040 for oils and 2060 for natural gas (Marilyn Radler, 2011).

Interest in the use of alternative fuels for diesel engines has risen with the decrease

of petroleum reserves and the rise in environmental consciousness. The fuel which will be

alternated to petroleum diesel must be suitable and acceptable technically,

environmentally and economically. Therefore, biodiesel which is produced from vegetable

oils and animal fats appeared to be the most suitable alternative fuel for petroleum diesel.

Biodiesel is a biodegradable, renewable and sustainable energy. It is derived from

vegetable oil or animal fats which are renewable sources. Aside from its biodegradability,

biodiesel is also renewable in contrast to scarce fossil fuel used which is formed from the

remnants of animals and plants that had lain in the earth for millions years. Biodiesel is

obtained via transesterification process of glycerides in oil with alcohols. It has been well-

reported that biodiesel was obtained from straight vegetable oil such as rapeseed, palm,

soybean, sunflower, algae as petroleum diesel substitute. Biodiesel can also be prepared

from waste cooking oil such as palm, sunflower, canola, corn, fish, and chicken fats

(Sharma and Singh, 2009).

Biodiesel is non-toxic and non-hazardous. In term of toxicity, biodiesel is the best

alternative that has been proven to be safe and not harmful to the environment. It does not

contain any inorganic compound that is non-biodegradable or toxic compound that will

bring adverse effects to human health and environment. Various tests verified that

biodiesel is non-toxic that poses no threat to human health (Zhou and Thomson, 2009).

Straight vegetable oils are more viscous than petroleum diesel. The higher

viscosity of straight vegetable oils will cause poor atomization. Thus, the diesel engine

needs some modifications when running straight vegetable oil in a diesel engine. Like

petroleum diesel, biodiesel operates in compression-ignition engines. When running a

diesel engine with biodiesel or biodiesel blends, the automobile does not require any

complex modification or conversion, although older vehicles may require replacement of

fuel lines and other rubber components. Biodiesel is often blended with petroleum diesel

in ratios of 2% (B2), 5% (B5), or 20% (B20). It can also be used as pure biodiesel (B100).

It has been well-reported that the engine performances of diesel engine run with biodiesel

or biodiesel blends are similar with diesel engine running with petroleum diesel (Singh

and Singh, 2010).

Biodiesel has many advantages compared to petroleum diesel and it plays an

important role in meeting future fuel requirements. Petroleum diesel fuels can contain up

to 20% polycyclic aromatic hydrocarbons. For an equivalent number of carbon atoms,

polycyclic aromatic hydrocarbons are up to three orders of magnitude more soluble in

water than straight chain aliphatic. The fact that biodiesel does not contain polycyclic

aromatic hydrocarbons makes it a safe alternative for storage and transportation (Hu et al.,

2005).

Biodiesel has 10-12% more oxygen than petroleum diesel. Since it is oxygenated,

it is a better lubricant than diesel fuel, increasing the life of engines, and is combusted

more completely. Indeed, many countries are introducing biodiesel blends to enhance the

lubricity of low-sulfur diesel fuels (Tyson, 2001).

Biodiesel has higher cetane number and flash point than petroleum diesel. The

higher flash point of biodiesel makes it a safer fuel to use, handle, and store. Biodiesel has

almost no sulfur, and does not contribute to greenhouse gaseous. Using biodiesel instead