Transesterification Of Used Frying Oil And Optimization For Biodiesel Production.
TRANSESTERIFICATION OF USED FRYING OIL AND OPTIMIZATION FOR BIODIESEL PRODUCTION
FADRAH HANIM BINTI AD SUHADAK
A thesis is submitted in fulfillment
of the requirements for the award of the degree of
Bachelor of Mechanical Engineering ( Thermal-Fluid) (Honours)
Faculty of Mechanical Engineering Universiti Teknikal Malaysia Melaka
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TRANSESTERIFICATION OF USED FRYING OIL AND OPTIMIZATION FOR BIODIESEL PRODUCTION
FADRAH HANIM BINTI AD SUHADAK
A thesis is submitted in fulfillment
of the requirements for the award of the degree of
Bachelor of Mechanical Engineering ( Thermal-Fluid) (Honours)
Faculty of Mechanical Engineering Universiti Teknikal Malaysia Melaka
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i
SUPERVISOR DECLARATION
“I hereby declare that I have read this thesis and in my opinion this report is sufficient in terms of scope and quality for the award of the degree of Bachelor of Mechanical
Engineering (Thermal-Fluid)”
Signature : ... Supervisor : MD ISA BIN ALI Date : ...
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DECLARATION
“I hereby declare that the work in this report is my own except for summaries and quotations which have been duly acknowledged.”
Signature : ...
Author : FADRAH HANIM BINTI AD SUHADAK Date : ...
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Dedicated to
My beloved parent Ad. Suhadak bin Nordin and Haslinda Hanim binti Jalil and family members for being supportive and always there through my thick and thin.
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ACKNOWLEDGEMENT
Alhamdulillah. Firstly, I would like to express my gratitude to Allah S.W.T for nikmah and blessing to give me an opportunity to complete my Final Year Project successfully. In addition, not to forget, to those who gave me morale support and prayers, especially my parents who had been through my thick and thin and for that I am grateful.
I would like to express my appreciation to my supervisor, Mr Md Isa bin Ali and Dr Mohd Zulkefli bin Selamat for continuous support, guidance, help and encouragement during this project.
Last but not least, an earnest gratitude is also expressed to friends and all people who supported me in any aspects during my Final Year Project.
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ABSTRACT
Used Frying Oil (UFO) has significant potential as the raw material or starting substance for biodiesel production. As known to public the amount of petroleum is decreasing each day. Therefore, there are many research is being conducted to introduce a new alternative fuel to be used in diesel engine. The objective of this research is to compare the characteristics and performance of sodium hydroxide (NaOH) and potassium hydroxide (KOH) used for alkaline-catalyzed transesterification. The variables selected to be optimized are concentration of catalyst, reaction of time and temperature in transesterification. The respond variables to be determined are the performance of yields and density of biodiesel from UFO as the starting. Moreover, this research studies on the effect of variables and type of catalyst on transesterification process. The transesterification process is conducted on a mixing stirrer, to give out consistency of temperature and stir towards the mixture of UFO, catalyst and methanol. The density of biodiesel produced will be measures using a S.G bottle. Moreover, design of experiment is determine by Taguchi’s Method to optimize the yield product and density of biodiesel. On top of that, the optimum value of KOH catalyst is at 0.63 wt.% concentration of catalyst, 60 ℃ reaction temperature and at 20 min reaction time produces yield production of 97.1648 g and 0.8755 g/cm3. Meanwhile for NaOH, the
optimum value is at 0.45 wt.% concentration of catalyst, 60 ℃ reaction temperature and
30 min reaction time generates yield production of 95.6810 g and density of 0.8720 g/cm3. Thus, it shows that KOH is the better catalyst compared to NaOH in
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ABSTRAK
Minyak Masak Terpakai (MMT) mempunyai potensi sebagai bahan mentah dalam penghasilan biodiesel. Objektif kajian adalah untuk membandingkan sifat dan prestasi pemangkin natrium hidroksida (NaOH) dan kalium hidroksida (KOH) yang digunakan dalam proses transeseterifikasi katalis-alkali. Sebagaimana diketahui umum, jumlah kandungan petroleum makin berkurang dari semasa ke semasa. Pelbagai kajian dilaksanakan untuk memperkenalkan minyak alternatif untuk digunakan dalam enjin diesel. Pemboleh ubah yang akan dioptimumkan adalah kepekatan katalis, suhu dan jangka masa reaksi. Pemboleh ubah bergerak balas adalah jumlah hasil dan ketumpatan biodiesel yang dihasilkan. Kajian ini turut merangkumi kesan pemboleh ubah dan katalis terhadap proses transesterifikasi. Ketumpatan biodiesel akan diukur menggunakan radas S.G. botol. Reka bentuk kajian akan dijalankan berdasarkan kaedah Taguchi untuk menghasilkan kadar hasil dan ketumpatan yang optimum. KOH mempunyai nilai optimum pada kepekatan pemangkin 0.63 wt.%, suhu reaksi yang bernilai 60℃ dan jangka masa reaksi selama 20 minit yang berjaya menghasilkan biodiesel sebanyak 97.1648 g dan ketumpuatan 0.8755 g/cm3. Manakala, NaOH mempunyai nilai optimum
pada kepekatan pemangkin 0.45 wt.%, suhu reaksi yang bernilai 60℃ dan jangka masa reaksi selama 30 minit yang berjaya menghasilkan biodiesel sebanyak 95.6810 g dan ketumpuatan 0.8720 g/cm3. Hasil kajian menunjukkan KOH adalah katalis terbaik jika
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TABLE OF CONTENT
CHAPTER TITLE PAGE
SUPERVISOR DECLARATION i
DECLARATION ii DEDICATION iii ACKNOWLEDGEMENT iv
ABSTRACT v
ABSTRAK vi
TABLE OF CONTENT vii
LIST OF TABLE xii
LIST OF FIGURE xiv
LIST OF ABREVIATION xvi
LIST OF APPENDICES xviii
CHAPTER 1 INTRODUCTION 1
1.1 Background Study 1
1.2 Objectives 2 1.3 Problem Statement 2
1.4 Scope of Study 3 1.5 Importance of Study 4
CHAPTER 2 LITERATURE REVIEW 5
2.1 Introduction 5
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CHAPTER TITLE PAGE
2.2.1 Characteristics and Properties of VO 5
2.2.2 Types of VO 6
2.2.2.1 Palm Oil 6
2.2.2.2 Sunflower Oil 6
2.2.3 Production and Consumption of Edible VO 7
2.3 UFO 9
2.3.1 Introduction 9
2.3.2 Environmental Problems of Disposing UFO 9
2.3.3 Production of UFO 10
2.3.4 Properties and Characteristics of UFO 11
2.4 Biodiesel 12
2.4.1 Introduction 12
2.4.2 Properties and Characteristics of Biodiesel 13 2.4.2.1 Density of Biodiesel 13 2.4.3 Advantages of Biodiesel 15 2.4.4 Disadvantages of Biodiesel Usage 16
2.5 Transesterification 17
2.5.1 Introduction 17
2.5.2 Factors Effecting Transesterification 18
2.5.3 Type of Catalyst 18
2.5.3.1 Alkaline Catalyst 19
2.5.3.2 Acid Catalyst 19
2.5.3.3 Enzyme Catalyst 20
2.5.4 Alcohol Used in Transesterification Process 20
2.6 Optimisation 22
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CHAPTER TITLE PAGE
2.6.2 Experimental Design 23 2.6.3 Types of Optimization Methods 24
2.6.3.1 Factorial 24
2.6.3.2 Surface Response 25
2.6.3.3 Mixture 26
2.6.3.4 Taguchi’s Approach to Experimental 27 Design
CHAPTER 3 METHODOLOGY 29
3.1 Introduction 29
3.2 Apparatus 29
3.3 Magnetic Stirrers 30
3.4 Digital Analytical Balance 31
3.5 Water Bath 32
3.6 Fuel Sampling 33
3.6.1 Collection of UFO 33
3.6.2 Pretreatment of UFO 34
3.7 Catalyst Selection 34
3.8 Alcohol Selection 35
3.9 Procedure 35
3.9.1 Transesterification Process 35 3.9.2 Transesterification Flow Chart 37
3.10 Setup of Experiment 38
3.11 Optimization using Taguchi’s Method 39 3.11.1 Factors and Level Determination 39 3.11.2 Signal to Noise Ratio (SNR) and Analysis of 40
Variance (ANOVA)
3.11.3 Conducting Preliminary Experiment 41 3.11.4 Optimization Result 42
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CHAPTER TITLE PAGE
3.9.5 Verifying Optimization Result 42 3.12 Measuring Density of Biodiesel 43
CHAPTER 4 RESULT AND DISCUSSION 45
4.1 Introduction 45
4.2 Yield Production of Biodiesel 45 4.2.1 Biodiesel Yield Production of KOH Catalyst 45 4.2.2 Biodiesel Yield Production of NaOH Catalyst 46 4.2.3 Comparison of KOH and NaOH catalyst on 47
Biodiesel Yield Production
4.3 Density of Biodiesel 48
4.3.1 Biodiesel Density of KOH Catalyst 49 4.3.2 Biodiesel Density of NaOH Catalyst 51
4.4 Analysis of ANOVA 53
4.4.1 Biodiesel Yield Production 53 4.4.1.1 Effect on Concentration of Catalyst 55 4.4.1.2 Effect on Reaction Temperature 56 4.4.1.3 Effect on Reaction Time 57 4.4.2 Density of Biodiesel 57 4.4.3 Ranking of Parameters on Yield Production 59 4.4.3.1 Ranking for KOH Catalyst 59 4.4.3.2 Ranking for NaOH Catalyst 60
4.5 Possible Error Causes 62
CHAPTER 5 CONCLUSION AND RECOMMENDATION 64
5.1 Introduction 64
5.2 Conclusion 64
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CHAPTER TITLE PAGE
BIBLIOGRAPHY 67
REFERENCES 68
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LIST OF TABLE
NUM. TITLE PAGE
2.1 World Production of VO 2008/2009 7
2.2 Physical Properties of UFO 11
2.3 Biodiesel Standard Specification 15 2.4 Comparison of Methylation and Ethylation of VO and Fats 22 3.1 Specifications of Magnetic Stirrers 30 3.2 Specification of Digital Analytical Balance 31 3.3 Specification of Water Bath 32
3.4 Properties of UFO 33
3.5 Chosen Parameter and Its Level for KOH 39 as the Catalyst
3.6 Chosen Parameter and Its Level for NaOH 40 as the Catalyst
3.7 Possible Combination with Three Parameers at Three 41 Levels for KOH Catalyst
3.8 Possible Combination with Three Parameers at Three 42 Levels for NaOH Catalyst
4.1 Table of KOH Catalyst on Yield Production 46 4.2 Table of NaOH Catalyst on Yield Production 47 4.3 Density Range of EN14214:2003, MS 2008:2008 and 49
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xiii
NUM. TITLE PAGE
4.4 Biodiesel Density of KOH Catalyst Fulfilled 50 Accordance to Standard EN 14214, MS 2008:2008
and EN 590:1999
4.5 Biodiesel Density of NaOH Catalyst Fulfilled 52 Accordance to Standard EN 14214, MS 2008:2008
and EN 590:1999
4.6 Comparison of Yield Production at 20 ˚C and 40 ˚C 56 4.7 Biodiesel Density of KOH for the Best Combination and 58
Poorest Combination Predicted by Taguchi’s Method
4.8 Biodiesel Density of NaOH for the Best Combination and 58 Poorest Combination Predicted by Taguchi’s Method
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LIST OF FIGURE
NUM. TITLE PAGE
2.1 Estimated Global Edible Oil Consumption on World 8 Population Growth
2.2 Annual Amount of UFO in Major Asian Cities 10 2.3 Confounding Effect of Fuel Density and Cetane Number 14
on Emission
2.4 Transesterification Reaction Producing Biodiesel 17
3.1 Magnetic Stirrers 30
3.2 Digital Analytical Balance 31
3.3 Water Bath 32
3.4 Filteration Process 34
3.5 Layer of Glycerin and Biodiesel 34 3.6 Layers of Biodiesel and Water for Washing Process 36 3.7 Flow Chart of Transesterification Process 37 3.8 Transesterification Experimental Setup 38 3.9 UFO, NaOH and KOH are Material Used 38
During Transesterification Process
3.10 S.G. Bottle 43
3.11 Weighing Filled S.G. Bottle 44 4.1 Comparison of KOH and NaOH on Biodiesel Yield 48
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NUM. TITLE PAGE
4.2 ANOVA for Biodiesel Yield Production of 53 KOH Catalyst
4.3 ANOVA for Biodiesel Yield Production of 54 NaOH Catalyst
4.4 Ranking of Parameters Based on Its Effect towards 59 KOH Yield Production
4.5 Taguchi Analysis on Ranking Parameters for KOH 60 Catalyst
4.6 Ranking of Parameters Based on Its Effect towards 61 NaOH Yield Production
4.7 Taguchi Analysis on Ranking Parameters for NaOH 61 Catalyst
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LIST OF ABREVIATION
ANOVA = Analysis of Variance CH3 ONa = Sodium Methoxide
CO = Carbon Monoxide CO2 = Carbon Dioxide
DOE = Design of Experiment FFA = Free Fatty Acid Fp = Flash Point H2S = Hydrogen Sulfide
HC = Hydrocarbon
HG = Heat Gross of Combustion k = Number of factors
KOH = Potassium Hydroxide L = Number of Level LCD = Liquid Crystal Display LTB = Larger the Better
N = Least Number of Experiment NaOH = Sodium Hydroxide
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NOx = Nitrogen Oxides
NTB = Nominal the Better OA = Orthogonal Array O&G = Oil and Gas
P = Parameter
PM = Particulate Matter S.G = Specific Gravity SNR = Signal to Noise Ratio STB = Smaller the Better TE = Trial and Error UFO = Used Frying Oil USD = United States Dollar
USDA = United States Department of Agriculture VO = Vegetable Oil
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LIST OF APPENDICES
NUM. TITLE PAGE
1 Transesterifiaction Flowchart 74
2 Measuring Density using S.G Botlle Flowchart 76 3 Taguchi Analysis of Biodiesel Yield Production 78
for KOH Catalyst
4 Taguchi Analysis of Biodiesel Yield Production 83 for NaOH Catalyst
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1
CHAPTER 1
INTRODUCTION
1.1. Background Study
Biodiesel fuel is defined as long chain fatty acid methyl or ethyl esters produced by the transesterification of vegetable oils or animal fats used as frying oils. Biodiesel is derived from vegetable oil or animal fats via transesterification with alcohol such as methanol and ethanol. It is also recommended to be used as a substitute of petroleum. It is due to biodiesel characteristics of an oxygenated, renewable, biodegradable and an environmental friendly biofuel with similar flow and combustion properties and also low emission profile. Moreover, with introduction of biodiesel it has help in reducing global warming gas emission like carbon dioxide, sulfur and carbon monoxide.
The benefits of biodiesel have garnered attention of many countries to conduct research and development in biodiesel industry. Unfortunately, the feedstock contains a tremendous amount of free fatty acids (FFA). The FFA is reacted with alkaline catalyst to produce soap, soap can exhibit the separation of methyl ester and glycerol and produce formation of emulsion during the washing procedure is conducted.
Optimization is selected to produce the highest rate of transesterification based on the several factors such as, catalyst concentration, reaction time and reaction temperature of transesterification. It is used to cut down time and cost production of biodiesel as optimal point is determine for further research or production of large scale biodiesel.
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1.2. Objectives
The objectives of this study are to conduct test on used frying oil (UFO), in order producing an alternatives biodiesel to be used in automotive industries. The test is conduct in laboratory scales using transesterification process to reduce the viscosity of the UFO. However, the transesterification process will be optimized to achieve the following objectives:
i. Compare the characteristic and performance of two commonly used catalyst used for alkaline– catalyzed transesterification.
ii. Optimize the variables that influence the transesterification. The variables involved will be reaction time, concentration of catalyst and reaction temperature
1.3. Problem Statement
Vegetable oil is being used extensively in food industry as frying oil. Mostly, the UFO will be discharged to pipe or thrown away without proper way of managing the UFO. This situation has lead to many environmental problems. For example, fat, oil and grease cause major problems to drains. When they are disposed down through the kitchen sinks or drains they cause blockages; when they enter rainwater pipes they cause pollution in streams and rivers.
Instead of throwing away the UFO, it can be transform to engine fuel. However, since the UFO contains higher viscosity compared to normal engine fuel, transesterification process is used to lower the viscosity indirectly producing biodiesel. Biodiesel is made from vegetable oil or animal fats through transesterification process, is recommended to be used as a substitute fuel for petroleum based diesel mainly because biodiesel comes from a renewable source, has a characteristics of biodegradable and environmentally friendly fuel, with an alike flow properties, combustion properties and low emission profile (Lotero E. et al., 2004). Indirectly, it helps to reduces global warming gas emissions such as carbon dioxide. Moreover, when biodiesel has no aromatics characteristics, it will reduce the
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3
harmful carbon monoxide and hydrocarbon emission in the exhaust gas compared to petroleum based diesel fuels (Peterson & Hustrulid, 1998).
Moreover, biodiesel can be used as an alternative fuel in transportation industry. All of natural sources such as petrochemical sources, coal and natural gas, are finite and at current usage rates will be consumed in the future (Meher et al, 2006). The depletion of world petroleum reserves and increased environmental concerns has gather recent interest in alternative sources for petroleum based fuels (Fukuda et al, 2001).
On top of that, the effect on type of catalyst, concentration of catalyst, reaction time and reaction temperature towards the performance of transesterification process is study. The performance of transesterification process refering to yield production of biodiesel. The density of optimum combination of variables to produce the highest and lowest amount of yield production is analyse whether it is in the standards of EN 14214:2003, MS 2008: 2008 and EN 590:1999 (Petroleum Diesel).
1.4. Scope of Study
Based on problem statement, this report will approach through the following scope: 1. The process variables that influence the transesterification of triglycerides such
as catalyst concentration, reaction time and reaction temperature will be investigated and optimised.
2. Types of catalyst to be used are potassium hydroxide (KOH) and sodium hydroxide (NaOH).
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1.5. Importance of Study
The importance of this study is to optimize the important variables and to compare the characteristic and performance of two commonly used catalyst used for alkaline –catalyzed transesterification process. With the important variables such as concentration of catalyst, reaction time and reaction temperature, being optimized only then, a high quality of biodiesel can be produce.
The high energy demand in the industrialized world and domestic sector, had caused pollution problems due to the widespread use of fossil fuels make it increasingly necessary to develop the renewable energy sources of smaller environmental impact than the fossil fuels such diesel fuels. The alternative fuel must be feasible, competitive in terms of economic, acceptable to the environment and readily available, and biodiesel fulfilled those properties. Moreover, biodiesel also has characteristics of biodegradability, non-toxic and contains low emission profiles as compare to diesel fuel.
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NTB = Nominal the Better
OA = Orthogonal Array
O&G = Oil and Gas
P = Parameter
PM = Particulate Matter S.G = Specific Gravity SNR = Signal to Noise Ratio STB = Smaller the Better
TE = Trial and Error
UFO = Used Frying Oil USD = United States Dollar
USDA = United States Department of Agriculture
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LIST OF APPENDICES
NUM. TITLE PAGE
1 Transesterifiaction Flowchart 74
2 Measuring Density using S.G Botlle Flowchart 76 3 Taguchi Analysis of Biodiesel Yield Production 78
for KOH Catalyst
4 Taguchi Analysis of Biodiesel Yield Production 83 for NaOH Catalyst
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CHAPTER 1
INTRODUCTION
1.1. Background Study
Biodiesel fuel is defined as long chain fatty acid methyl or ethyl esters produced by the transesterification of vegetable oils or animal fats used as frying oils. Biodiesel is derived from vegetable oil or animal fats via transesterification with alcohol such as methanol and ethanol. It is also recommended to be used as a substitute of petroleum. It is due to biodiesel characteristics of an oxygenated, renewable, biodegradable and an environmental friendly biofuel with similar flow and combustion properties and also low emission profile. Moreover, with introduction of biodiesel it has help in reducing global warming gas emission like carbon dioxide, sulfur and carbon monoxide.
The benefits of biodiesel have garnered attention of many countries to conduct research and development in biodiesel industry. Unfortunately, the feedstock contains a tremendous amount of free fatty acids (FFA). The FFA is reacted with alkaline catalyst to produce soap, soap can exhibit the separation of methyl ester and glycerol and produce formation of emulsion during the washing procedure is conducted.
Optimization is selected to produce the highest rate of transesterification based on the several factors such as, catalyst concentration, reaction time and reaction temperature of transesterification. It is used to cut down time and cost production of biodiesel as optimal point is determine for further research or production of large scale biodiesel.
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1.2. Objectives
The objectives of this study are to conduct test on used frying oil (UFO), in order producing an alternatives biodiesel to be used in automotive industries. The test is conduct in laboratory scales using transesterification process to reduce the viscosity of the UFO. However, the transesterification process will be optimized to achieve the following objectives:
i. Compare the characteristic and performance of two commonly used catalyst used for alkaline– catalyzed transesterification.
ii. Optimize the variables that influence the transesterification. The variables involved will be reaction time, concentration of catalyst and reaction temperature
1.3. Problem Statement
Vegetable oil is being used extensively in food industry as frying oil. Mostly, the UFO will be discharged to pipe or thrown away without proper way of managing the UFO. This situation has lead to many environmental problems. For example, fat, oil and grease cause major problems to drains. When they are disposed down through the kitchen sinks or drains they cause blockages; when they enter rainwater pipes they cause pollution in streams and rivers.
Instead of throwing away the UFO, it can be transform to engine fuel. However, since the UFO contains higher viscosity compared to normal engine fuel, transesterification process is used to lower the viscosity indirectly producing biodiesel. Biodiesel is made from vegetable oil or animal fats through transesterification process, is recommended to be used as a substitute fuel for petroleum based diesel mainly because biodiesel comes from a renewable source, has a characteristics of biodegradable and environmentally friendly fuel, with an alike flow properties, combustion properties and low emission profile (Lotero E. et al., 2004). Indirectly, it helps to reduces global warming gas emissions such as carbon dioxide. Moreover, when biodiesel has no aromatics characteristics, it will reduce the
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petroleum based diesel fuels (Peterson & Hustrulid, 1998).
Moreover, biodiesel can be used as an alternative fuel in transportation industry. All of natural sources such as petrochemical sources, coal and natural gas, are finite and at current usage rates will be consumed in the future (Meher et al, 2006). The depletion of world petroleum reserves and increased environmental concerns has gather recent interest in alternative sources for petroleum based fuels (Fukuda et al, 2001).
On top of that, the effect on type of catalyst, concentration of catalyst, reaction time and reaction temperature towards the performance of transesterification process is study. The performance of transesterification process refering to yield production of biodiesel. The density of optimum combination of variables to produce the highest and lowest amount of yield production is analyse whether it is in the standards of EN 14214:2003, MS 2008: 2008 and EN 590:1999 (Petroleum Diesel).
1.4. Scope of Study
Based on problem statement, this report will approach through the following scope: 1. The process variables that influence the transesterification of triglycerides such
as catalyst concentration, reaction time and reaction temperature will be investigated and optimised.
2. Types of catalyst to be used are potassium hydroxide (KOH) and sodium hydroxide (NaOH).
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1.5. Importance of Study
The importance of this study is to optimize the important variables and to compare the characteristic and performance of two commonly used catalyst used for alkaline –catalyzed transesterification process. With the important variables such as concentration of catalyst, reaction time and reaction temperature, being optimized only then, a high quality of biodiesel can be produce.
The high energy demand in the industrialized world and domestic sector, had caused pollution problems due to the widespread use of fossil fuels make it increasingly necessary to develop the renewable energy sources of smaller environmental impact than the fossil fuels such diesel fuels. The alternative fuel must be feasible, competitive in terms of economic, acceptable to the environment and readily available, and biodiesel fulfilled those properties. Moreover, biodiesel also has characteristics of biodegradability, non-toxic and contains low emission profiles as compare to diesel fuel.