Green chemistry in the first year lab: Using biodiesel to teach general chemistry principles. Overview:

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1 Green chemistry in the first year lab: Using biodiesel to teach general chemistry principles Richard artmann Nazareth ollege hemistry Department verview:! What is green chemistry?! What is Biodiesel?! hemistry of Biodiesel Production! Why is Biodiesel a green product?! General chemistry concepts! Student Research Green hemistry is: the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances. Green chemistry is a highly effective approach to pollution prevention because it applies innovative scientific solutions to real-world environmental situations. EPA! What is Biodiesel?

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3 ! Availability ~ 1x 6 gal/yr! Uses: fuel, fertilizer, animal feed, cosmetics, soap, others! ontaminants: water, food particles

4 hemistry of Biodiesel Production R 1 3 R 1 R 2 Na R 2 R 3 3 R 3 R 1 = 18 ( Poly-unsarurated Linoleic acid ) R 2 = 18 ( Mono-unsaturated leic acid ) R 3 = 16 ( Saturated Palmitic acid )

5 Why is Biodiesel a green product? 1. Prevent waste: 2. Design safer chemicals and products: 3. Design less hazardous chemical syntheses: 4. Use renewable feedstocks: 5. Use catalysts, not stoichiometric reagents: 6. Avoid chemical derivatives: 7. Maximize atom economy: 8. Use safer solvents and reaction conditions: 9. Increase energy efficiency:. Design chemicals and products to degrade after use: 11. Analyze in real time to prevent pollution: General hemistry Lab Lab Manual -vs- No Lab Manual Lab notebook Written lab reports ral lab reports 12. Minimize the potential for accidents:

6 Mechanics General hemistry Principles Timing ommunication Acid - Base titration Presentation ontent Stoichiometry Background hemistry Data/Results onclusions Question/Answers Total Intermolecular forces olligative properties alorimetry Research the reaction of fats/oils with respect to a reaction we do not want ( saponification ) but which is likely to happen to a small degree. We will need to discuss, as a class, what measures we can take to minimize this reaction from happening. Research the reaction of fats and oils with sodium methoxide to induce a transesterification reaction. Specifically to produce biodiesel ( also known as FAME or fatty acid methyl esters ).

7 Familiarize yourself with sodium methoxide, its synthesis ( more than one possible way to make this ) and the hazards involved with making and using this substance. Make sure you print and thoroughly read through the MSDS for all reagents involved Research the chemical formula, molecular structure, and physical properties ( in preparation for characterizing the products of your synthesis as well as preparation for the first lab practical ) of the following substances: soybean oil as well as the oil you extracted Glycerine Methanol Biodiesel petroleum diesel 1. Titration of oil for FFA content All oil will have some FFA which requires extra Na for neutralization. 2. Stoichiometry of the transesterification reaction. ~ 3.5 g Na / L oil ( + Na for FFA ) ~ 200 ml Me / L oil Prepare solution of 1g Na / 1 L 2 0 Dissolve 1 ml oil in ml 2-propanol 2 drops phenolphthalein R 1 R 2 N a R 1 R 2 ml Na solution added = g Na needed to neutralize FFA R 1 = 1 8 ( P oly-u n sarurated L ino le ic acid ) R 2 = 1 8 ( M o no -u ns atu rated leic a cid ) R 3 = 1 6 ( S atu rated P alm itic acid ) R 3 3 R 3

8 3. olligative properties: Gel point depression 3. Intermolecular forces: a) Separation of oil/water b) Mixing of oil and NaMe/Me c) Separation of products d) Where s the excess Me? & recovery e) Washing the biodiesel f) Physical properties of reagents/products i) density ii) viscosity ( approximate ) iii) cloud point iv) acid number vi) others determined by students

9 5. alorimetry of the transesterification eat capacity of biodiesel Enthalpy of combustion Relate to calculated value using average bond enthalpies and percent fatty acid composition of soybean oil Student research: ptimization of technique Enzyme catalyzed process G analysis of biodiesel from various source oils Fractional distillation and identification of species involved in clouding and color Use of biodiesel as organic reaction solvent Acknowledgements! Nazareth ollege Faculty Development ommittee! Paula hilds (The Summer Visions Fund )! David Verdine! Glen Labenski! hris Bowen! 2005/2006 General hemistry Students