GRADUATE AND POSTDOCTORAL STUDIES FINAL ORAL EXAMINATION

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1 GRADUATE AND POSTDOCTORAL STUDIES MCGILL UNIVERSITY FINAL ORAL EXAMINATION FOR THE DEGREE OF DOCTOR OF PHILOSOPHY OF PETER ADEWALE DEPARTMENT OF BIORESOURCE ENGINEERING INFLUENCE OF ULTRASONIC MIXING ON ENZYME CATALYZED BIODIESEL PRODUCTION FROM WASTE ANIMAL FATS June 08, :15 AM Raymond Building Room R3-045 McGill University, Macdonald Campus COMMITTEE: Dr. Sébastien Faucher (Pro-Dean), Natural Resource Sciences Dr. Michael Ngadi (Co-supervisor), Bioresource Engineering Dr. Marie- Josee Dumont (Co-supervisor), Bioresource Engineering Dr. Vijaya Raghavan (Departmental Chair), Bioresource Engineering Dr. Mark Lefsrud (Internal Member), Bioresource Engineering Dr. Varoujan Yaylayan (External Member), Food Science & Agricultural Chemistry Dr. Martin Kreiswirth, Dean of Graduate and Postdoctoral Studies Members of the Faculty and Graduate Students are invited to attend

2 ABSTRACT This study investigated the influence of ultrasonic mixing on enzyme catalyzed biodiesel production from waste animal fats. Non-edible feedstocks such as animal fat wastes (AFW) have recently increased in popularity as alternatives to vegetable oils in the production of biodiesel. They are low cost, mitigate environmental damage and increase the quality of the resultant biodiesel fuel (low NOx emissions, high cetane number and oxidative stability). But the presence of a high content in free fatty acid (FFA) in AFW has been seen as a challenge, especially when synthesized by alkaline-catalyzed transesterification. A comprehensive investigation of the rheological, thermal and physicochemical properties of AFW (tallow, lard, choice white grease and yellow grease) were studied. The physicochemical properties of animal fat waste samples and the correlation of these properties to their thermal and rheological behaviors were elucidated. Pure lard was used to monitor the effects of impurities on the rheological and thermal properties of the animal fat wastes. It was established that the presence of impurities had effects on the rheological and thermal properties of fats. Additionally, due to the high level of FFA present in the wastes, transesterification cannot be applied directly. It will be necessary to reduce the FFA level by using acid pretreatment or enzyme catalyzed transesterification Further study was conducted to develop a non-destructive technique to determine iodine value (IV) and free fatty acids (FFA) content of four different animal fat wastes and their blends using Fourier transform near-infrared spectroscopy (FT-NIR). Chemometric analysis by Partial Least Squares (PLS) regression was used to correlate spectral data with IV and FFA reference values of the samples. The effects of four spectra pre-processing (first derivative (FD), second derivative (SD), multiplicative scatter correction (MSC) and vector normalization (VN)) methods were investigated to predict the reproducibility and robustness of the PLS-NIR model developed. PLS-NIR models developed using first derivative and second derivative spectral preprocessing methods were the best for both IV and FFA content analysis (For IV, FD; R 2 = 98.70, RMSEE = 1.40 gi2/100g, RPD = 8.76, SD; R 2 = 98.92, RMSEE = 1.28 gi2/100g, RPD = 9.64 while For FFA, FD; R 2 = 99.91, RMSEE = 0.195%, RPD

3 = 34.00, SD; R 2 = 99.93, RMSEE = 0.182%, RPD = 36.8). Overall, the results of this study demonstrate the suitability of FT-NIR spectroscopy for the quality control analysis of feedstocks for biodiesel production. The use of ultrasonic processing was evaluated for its ability to achieve adequate mixing while providing sufficient activation energy for the enzymatic transesterification of waste tallow. A Ping Pong Bi Bi kinetic model approach was employed to study the effect of ultrasonic amplitude on the enzymatic transesterification. Optimal conditions for ultrasound-assisted biodiesel production from waste tallow were fat:methanol molar ratio, 1:4; catalyst level 6% (w/w of fat); reaction time, 20 min (30 times less than conventional batch processes); ultrasonic amplitude 40% at 5 khz. Reversed phase high performance liquid chromatography indicated the biodiesel yield to be 85.6 ± 0.08%. The kinetic model results revealed interesting features of ultrasound assisted enzyme-catalyzed transesterification (as compared to conventional system): at ultrasonic amplitude 40%, the reaction activities within the system seemed to be steady after 20 min which means the reaction could proceed with or without ultrasonic mixing. Similar investigation was carried out on waste lard to study the effects of ultrasonic parameters (amplitude, cycle and pulse) and major reaction factors (molar ratio and enzyme concentration) on the reaction kinetics of biodiesel production by immobilized lipase [Candida antarctica Lipase B (CALB)]. A yield of 96.8 ± 0.02% was attained in 20 min at an ultrasonic amplitude (40%) at 5 khz, fat:methanol molar ratio (1:4) and catalyst level 6% (w/w of fat). The fitted curves of the kinetic mechanism showed a sigmoidal curve due to mass transfer limitations which controlled the process at the beginning of the reaction. At ultrasonic amplitude 40%, the reaction activities within the system seemed to have steadied after 20 min which means the reaction could proceed with or without ultrasonic mixing. The feasibilities of choice white grease as biodiesel feedstock and the effects of ultrasonic parameters (amplitude, cycle and pulse) and major reaction factors (molar ratio and enzyme concentration) on the reaction kinetics of biodiesel production by immobilized lipase [Candida antarctica Lipase B (CALB)] were investigated. A yield of 98.2% was attained in 20 min at an ultrasonic amplitude (40%) at 5

4 khz, fat:methanol molar ratio (1:4) and catalyst level 6% (wt/wt of fat). The kinetic model results also showed ultrasound assisted enzyme-catalyzed transesterification reaction activities at ultrasonic amplitude 40% to be steady after 20 min. The fitted curves of the kinetic mechanism equally revealed a sigmoidal curve due to mass transfer limitations which controlled the process at the beginning of the reaction. The results of this study give a better understanding of the reaction rates with respect to individual reactants and system parameters which is a great advantage for design and construction of the biodiesel reactors using ultrasonic mixing. Curriculum Vitae 2010 Now PhD Study, Bioresource Engineering, McGill University, Ste-Anne-de-Bellevue, QC, Canada M.Sc. Agricultural and Environmental Engineering, University of Ibadan, Ibadan, Oyo State, Nigeria B.Eng. Agricultural Engineering, University of Ilorin, Ilorin, Kwara State, Nigeria. AWARDS Int'l Doctoral Award (MIDAs), McGill University, Montreal, Canada ( ). Grad Excellence Award-00066, McGill University, Montreal, Canada ( ). Great Travel Awards, McGill University, Montreal, Canada ( ). Provost s Grad Fellow-AG Award, McGill University, Montreal, Canada (2010). Best Graduate Prize, Faculty of Engineering and Technology, University of Ilorin, Nigeria ( ) Best Graduate Prize, Agricultural Engineering Department, University of Ilorin, Nigeria ( ) PUBLICATIONS 1) Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Enzyme-catalyzed synthesis of biodiesel from waste tallow

5 assisted by ultrasonication. Ultrasonics Sonochemistry, 27, 1-9; doi: /j.ultsonch ) Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Recent Trends of Biodiesel Production from Animal Fat Wastes and Associated Production Techniques. Renewable and sustainable energy reviews, 45, ; doi: /j.rser ) Peter Adewale, Ogan Mba, Marie-Josee Dumont, Michael Ngadi and Robert Cocciardi, Determination of the iodine value and the free fatty acid contents of waste animal fat blends using FT-NIR. Vibrational spectroscopy, 72, 72-78; dx.doi.org/ /j.vibspec ) Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Rheological, thermal, and physicochemical characterization of animal fat wastes for use in biodiesel production. Energy technology, 2, ; dx.doi.org/ /ente ) Ogan Mba, Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Application of near-infrared spectroscopy to characterize binary blends of palm and canola oils. Industrial Crops and Products, 61, ; dx.doi.org/ /j.indcrop ) Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Enzyme-catalyzed synthesis and kinetics of ultrasonic assisted methanolysis of waste lard for biodiesel production. Revised paper submitted to Chemical Engineering Journal. 7) Peter Adewale, Marie-Josee Dumont and Michael Ngadi, Enzyme-catalyzed synthesis and kinetics of ultrasonic assisted methanolysis of waste choice white grease for biodiesel production. Submitted to Energy and Fuel (Under review). CONFERENCE PRESENTATIONS 1) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, Kinetic Study of Biodiesel Production by Ultrasound-assisted Enzymatic Transesterification of Waste Tallow. Proceedings of 12 th Annual World Congress on Industrial Biotechnology, Montreal, QC, CA. 2) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, Enzymatic synthesis and kinetics of ultrasonic assisted transesterification of waste lard for biodiesel production. Paper number: 026. Proceedings of the Canadian Society for Bioengineering (CSBE-SCGAB) annual conference, Edmonton, AB, CA.

6 3) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, FT- NIR Determination of Iodine Value and Free Fatty Acid content of Waste Animal Fat Blends. Paper number: Proceedings of American Society of Agricultural and Biological Engineers (ASABE) Annual International Conference, Montreal, QC, CA. 4) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, Fast Methanolysis of Waste Tallow for Biodiesel Production Assisted by Ultrasonication. Paper number Northeast Agricultural and Biological Engineering Conference (NABEC), Kemptville, ON, CA. 5) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, Thermal and Physicochemical Properties of Waste Animal Fats. Paper number FPE-341. Proceedings of American Society of Agricultural and Biological Engineers (ASABE) Annual International Conference, Kansas city, Missouri, USA. 6) Adewale, P., Marie-Josee Dumont and M.O. Ngadi, Effects of Composition on Waste Animal Fat Rheology and Crystallization. Paper number Northeast Agricultural and Biological Engineering Conference (NABEC), Altoona, PA, USA. 7) Adewale, P., and M.O. Ngadi, CFD Modeling of Liquid- Liquid Two Phase Flow in Biodiesel Production. Paper number Northeast Agricultural and Biological Engineering Conference (NABEC), Orillia, ON, CA. 8) Adewale, P., and M.O. Ngadi, Modeling Hydrodynamics of Immiscible Liquid (Methanol-Oil). Paper number Northeast Agricultural and Biological Engineering Conference (NABEC), South Burlington, VT, USA.