OPTIMIZATION VIA RESPONSE SURFACE METHODOLOGY AND KINETIC STUDY ON JATROPHA ETHLYL ESTER PRODUCTION USING
POTASSIUM HYDROXIDE AS CATALYST
KIMBERLEI MAY ANOG LALUAN
SUBMITTED TO THE FACULTY OF THE
COLLEGE OF ENGINEERING AND AGRO-INDUSTRIAL TECHNOLOGY UNIVERSITY OF THE PHILIPPINES LOS BAÑOS
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
DEGREE OF
BACHELOR OF SCIENCE IN CHEMICAL ENGINEERING
APRIL 2009
ACCEPTANCE SHEET
The report attached hereto, entitled “OPTIMIZATION VIA RESPONSE SURFACE METHOD AND KINETIC STUDY ON JATROPHA ETHYL ESTER PRODUCTION USING POTASSIUM HYDROXIDE AS CATALYST” prepared and submitted by KIMBERLEI MAY A. LALUAN in partial fulfillment of the requirements for the degree of BACHELOR OF SCIENCE IN CHEMICAL ENGINEERING, is hereby accepted.
___________________________________ ________________________________
Engr. BUTCH G. BATALLER Prof. MYRA G. BORINES Panel Member Panel Member
Date Signed Date Signed
_________________________________
Dr. LAURA J. PHAM Co-adviser
Date Signed
_________________________________
Prof. REX B. DEMAFELIS Adviser
__________________
Date Signed
_________________________________
Dr. JOVITA L. MOVILLON Chair
Department of Chemical Engineering __________________
Date Signed
_________________________________
Dr. ARSENIO N. RESURRECCION Dean
College of Engineering and Agro-Industrial Technology University of the Philippines Los Baños
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TABLE OF CONTENTS
PAGE NUMBER
TITLE PAGE i
APPROVAL PAGE ii
ACKNOWLEDGEMENT iii
TABLE OF CONTENTS iv
LIST OF TABLES vi
LIST OF FIGURES viii
LIST OF APPENDICES x
ABSTRACT xi
1. INTRODUCTION 1
1.1. Background of the Study 1
1.2. Significance of the Study 3
1.3. Objectives of the Study 3
1.4. Scope and Limitations of the Study 4
1.5. Date and Place of the Study 5
2. REVIEW OF RELATED LITERATURE 6
2.1. Jatropha Plant 6
2.2. Biodiesel 7
2.3. Oil Refining 8
2.3.1. Degumming 8
2.3.2. Free Fatty Acid Reduction 9
2.4. Transesterification Reaction 10
2.5. Thin Layer Chromatography 15
2.6. Rate of Chemical Reaction 16
2.7. Available Related Studies 18
3. METHODOLOGY 21
3.1. Materials and Reagents 21
3.2. Glasswares and Equipment 21
3.3. Procedure 21
3.3.1. Pretreatment 21
3.3. 2. Base-Catalyzed Transesterification 24
3.3.3. Design experiment 26
3.3.4. Thin Layer Chromatography 28
3.3.5. Optimum Point Determination 28
3.3.6. Time Profile for the Transesterification 29
4. RESULTS AND DISCUSSION 30
4.1. Optimization on the Production of Ethyl Ester 30 4.2. Material Balance on the Production of Dried Biodiesel 46 4.3. Determination of the Reaction Order and Rate Constant 47
5. SUMMARY AND CONCLUSION 53
6. RECOMMENDATIONS 55
BIBLIOGRAPHY 56
APPENDICES 59
LIST OF TABLES
TABLE TITLE PAGE NUMBER
3.1 Levels of Factors for the Central Composite Design 27 3.2 Experiment matrix for the optimization of ethyl ester 27
production using Response Surface Methodology
4.1.1 Experimental data obtained for the optimization of 31 ethyl ester production
4.1.2 ANOVA for the response surface 2FI model 32
4.1.3 ANOVA for the response surface quadratic model 34
4.1.4 Verification of predicted optimum points 45
4.2.1 Transesterification mass balance of biodiesel 47 production at optimum condition obtained
4.3.1 Guessed values of the order of reaction in trial 1 50 time profile
4.3.2 Guessed values of the order of reaction in trial 2 51 time profile
4.3.3 The highest correlation coefficient obtained in the 51 Experiment
A.1 Standardization of the NaOH solution 59
C.1 Data obtained from transesterification of the 28 runs 61 D.1 Sequential Model Sum of Squres (Type I) (Purity) 63
D.2 Lack of Fit tests (Purity) 63
D.3 Model Summary Statistics (Purity) 63
E.1 Sequential Model Sum of Squres (Type I) (Conversion) 64
E.2 Lack of Fit tests (Conversion) 64
E.3 Model Summary Statistics (Conversion) 64
F.1 Constraints for optimum point determination 65
F.2 Predicted optimum points 65
F.3 Raw data on the verification of optimum points 67 G.1 Time profile of trial 1 transesterification at optimum 68
condition
G.2 Time profile of trial 2 transesterification at optimum 68 condition
LIST OF FIGURES
FIGURE TITLE PAGE NUMBER
2.1 Chemical structure of diglyceride and monoglyceride 10 2.2 Overall transesterification process of crude oil 11
2.3 Hydrolysis of triglyceride 12
2.4 Saponification fram an ester 12
2.5 Reaction mechanism of base-catalyzed 14
transesterification of vegetable oil
3.1 Settling of crude Jatropha curcasoil 22
3.2 Degumming of filtered crude oil 23
3.3 Transesterification set-up 25
3.4 Biodiesel samples 26
3.5 Time Profile Setup 29
4.1.1 The effect of interaction of the amount of ethanol with 36 reaction temperature on the purity of ethyl ester.
4.1.2 A model graph of the oil conversion to ethyl ester in 37 terms of ethanol:oil molar ratio and temperature
4.1.3 The effect of interaction between KOH and reaction 38 temperature on the purity of ethyl ester
4.1.4 A model graph of the oil conversion to ethyl ester in 39 terms of KOH: oil molar ratio and temperature
4.1.5 The effect of reaction time and reaction temperature on 40 The purity of ethyl ester
4.1.6 A model graph of the oil conversion to ethyl ester in 41 terms of reaction time and temperature
4.1.7 The effect of interaction between the amount of KOH 42 and ethanol on the purity of ethyl ester
4.1.8 A model graph of the oil conversion to ethyl ester in 43 terms of ethanol and potassium hydroxide
4.1.9 The effect of interaction between the amount of ethanol 44 and reaction time on the purity of ethyl ester
4.1.10 A model graph of the oil conversion to ethyl ester in 44 terms of ethanol and reaction time.
4.3.1 Trial 1 time profile for the production of ethyl ester at the 48 optimum condition obtained.
LIST OF APPENDICES
APPENDIX TITLE PAGE NUMBER
A Preparation and Standardization of NaOH Solution 59
B Free Fatty Acid Analysis 60
C Transesterification Raw Data 61
D Statistical Analysis of the Design Model for the 63 Purity Response Surface
E Statistical Analysis of the Design Model for the 64 Conversion Response Surface
F Optimization on Ethyl Ester Production using 65
Response Surface Methodology
G Kinetics Raw Data 68
H Material Safety Data Sheet 70
ABSTRACT
LALUAN, KIMBERLEI MAY A., College of Engineering and Agro-Industrial Technology, University of the Philippines at Los Baños, April 2009. OPTIMIZATION VIA RESPONSE SURFACE METHODOLOGY AND KINETIC STUDY ON JATROPHA ETHYL ESTER PRODUCTION USING POTASSIUM HYDROXIDE AS CATALYST.
Adviser: Prof. Rex. B. Demafelis Co-Adviser: Dr. Laura J. Pham
The optimization of the production of ethyl ester using potassium hydroxide was conducted using the Response Surface Methodology. The factors considered were the reaction temperature of 29°C to 36 °C, ethanol to oil molar ratio of seven to eight, potassium hydroxide to oil molar ratio of 0.29 to 0.32, and reaction time of three to four hours. The responses considered in the optimization of ethyl ester production were the conversion of oil to ethyl ester and its purity. The matrix of the optimization experiment was generated using the Design Expert 7.1.4. It was found that two- factor interaction and quadratic model were the models fitted for the purity and conversion of oil to ethyl ester, respectively. The optimum point predicted and verified experimentally which has the conditions of 7.86 EtOH:oil molar ratio and 0.28 KOH:oil molar ratio, 29.61 °C reaction temperature and 3.05 hours reaction time, produced an ethyl ester with a purity of 97.6%
and as high as 90.31% conversion. A time profile of the transesterification at the obtained optimum conditions was also performed to determine the kinetics of the reaction. The overall forward order of reaction evaluated was 1.108 with a constant rate of formation of ethyl ester of 0.10443 (wt% triglyceride)-0.108min-1.
