Biodiesel

Question 1

What is Biodiesel?

Answer 1

a fuel comprising long-chain faCy acid methyl esters (FAMEs) derived from vegetable oils or animal fats, designated B100 and mee0ng standard requirements.

Question 2

What are some commercial methods in making Biodiesel?

Answer 2

• Base-catalyzed transesterifica0on of the oil with alcohol (approach we will use)
• Acid-catalyzed esterifica0on of the oil with methanol
• Saponifica0on of the oil to yield free faCy acids, followed by acid catalyzed esterifica0on

Question 3

What are fatty acids?

Answer 3

FaCy acids are carboxylic acids (R-CO2H) whose unbranched nonpolar hydrocarbon R-group is usually 8-18 carbon atoms long . Those found in common cooking oils such as canola, olive, vegetable , etc. mostly range from 16 to 20 carbons chain.

Question 4

What are unsaturated fatty acids?

Answer 4

UNSATURATED faCy acids have one or more C=C bond (mono-unsaturated or poly-unsaturated) in the chain and are found in unsaturated fats.

Question 5

What are saturated fats?

Answer 5

SATURATED faCy acids do not have C=C bonds in the chain and are present in saturated fats.

Question 6

What is transesterification?

Answer 6

involves transformation of an ester into another one through interchange of the alkoxy group.

Question 7

What is the limiting reagent in this reaction? Which reagent is in excess and why is this reagent required in excess?

Answer 7

Limiting reagent: Triglycerides

- Methanol used in excess in order to increase product yield due to Le Chatlier’s principle.

Question 8

What are the starting materials, reagents, catalysts and products in transesterification?

Answer 8

SM: Triglyceride
Reag: Methanol
Catalyst: NaOMe
Products: FAMEs and Glycerol (or glycerin)

Question 9

How is waste disposed in Biodiesel lab?

Answer 9

Organic liquid hazardous waste container

Question 10

How was the product analyzed and what differences were you looking for?

Answer 10

NMR,
1) disappearance of peaks due to tryglycerides -CH2-
2) FAMEs have large singlet peak due to Methoxy protons ~3.5. Products differentiated by ratio of methoxy to bis-allylic protons.
Canola: 2.5-3
Olive: 8-8.5
Veg: 1.5-2

Question 11

What is a coupling constant?

Answer 11

Distance between the individual peaks of multiplet.

Question 12

What layer will glycerol be after separation?

Answer 12

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