Final Exam- Biodiesel Portion

Question 1

What is biodiesel? (general)

Answer 1

A domestic, renewable fuel for engines that is derived from natural oils

Question 2

What is biodiesel? (technical)

Answer 2

a fuel that is made up of long-chain fatty acid methyl esters (FAMEs) that is derived from vegetable oils or animal fats

Question 3

How do you make biodiesel?

Answer 3

Either a) base-catalyzed transesterification of the oil with methanol or b) acid-catalyzed esterification of the oil with methanol

Question 4

What approach to making biodiesel was used in this lab?

Answer 4

base-catalyzed transesterification

Question 5

What is a fatty acid?

Answer 5

carboxylic acids that have an R group of 8-18 carbons. Fatty acids are commonly found in cooking oils like canola, olive, vegetable, and are around 16-20 Cs long

Question 6

What’s an unsaturated fatty acid?

Answer 6

Contains one or more carbon carbon double bond

Question 7

What’s a saturated fatty acid?

Answer 7

Do not contain carbon carbon double bonds at all

Question 8

What are the major component fatty acids in the oils that are used in this experiment?

Answer 8

a-linolenic, linoleic, oleic, and palmitic acids

Question 9

Picture of the above acids

Answer 9

picture from the slides

Question 10

What is transesterification?

Answer 10

the transformation of one ester into another ester through the interchange of the alkoxy group

Question 11

Why use base-catalyzed production?

Answer 11

It is economically friendly. Low rxn temperature and pressure, minimal side rxns, faster than acid-catalyzed, less corrosive than acid-catalyzed

Question 12

Draw the transesterification reaction that is specific to this experiment

Answer 12

Picture of the slide

Question 13

Draw the mechanism of transesterification of oils

Answer 13

Picture of the slide

Question 14

What are the expected FAMEs of this experiment?

Answer 14

methyl stearate
methyl linoleate
methyl oleate
methyl palmitate
methyl a-linoleate

Question 15

Which FAMEs are in canola oil?

Answer 15

methyl oleate
methyl linoleate
methyl a-linoleate

Question 16

Which FAMEs are in olive oil?

Answer 16

methyl oleate
methyl palmitate
methyl linoleate

Question 17

Which FAMEs are in vegetable oil?

Answer 17

methyl oleate
methyl linoleate
methyl stearate

Question 18

Draw the structures of the FAMEs

Answer 18

Picture from slide

Question 19

What characterization technique is used in this experiment?

Answer 19

H-NMR of the FAMEs is done

Question 20

What does the number of signals mean on H-NMR?

Answer 20

how many different kinds of protons are present

Question 21

What does the position on H-NMR mean?

Answer 21

this is the chemical shift, which shows how shielded the proton is

Question 22

What does the intensity on H-NMR mean?

Answer 22

The number of protons of a specific type

Question 23

What does peak-splitting mean on H-NMR?

Answer 23

the number of neighboring protons

Question 24

What is the starting material?

Answer 24

triglyceride

Question 25

What is the limiting reagent in this experiment?

Answer 25

triglyceride

Question 26

What is the excess reagent in this experiment?

Answer 26

methanol

Question 27

What is created when you add water to sodium methoxide?

Answer 27

sodium hydroxide
methanol

Question 28

Where should FAMEs be disposed of?

Answer 28

organic liquid hazardous chemical waste container

Question 29

Which way does the excess reagent shift the equilibrium to in this experiment?

Answer 29

to the right

Question 30

What are you looking for on the H-NMR to decipher your product?

Answer 30

appearance of peak due to OCH3
disappearance of CH2 peak due to triglyceride
Intensity of the peaks will change

Question 31

What is the top layer made of in this experiment?

Answer 31

FAMEs and methanol

Question 32

What is the bottom layer made of in this experiment?

Answer 32

glycerol

Question 33

What does NaOCH3 serve as in this experiment?

Answer 33

catalyst