Production of Biodiesel

Diesel versus Biodiesel

Diesel• Petroleum product (Petra =

rock; oleum = oil)• Made from crude oil which

takes millions of years to form

• Non-renewable resource

Biodiesel• Can be made from vegetable

oils and animal fats• Most commonly made from

soybean and canola oil, vegetable crops that can be grown annually

• Can be made from waste oils and greases (from fryers of restaurants and factories)

• Renewable resource

How is biodiesel made?

• Primary source of biodiesel is vegetable oil

• Most plant oils and animal fats are triglycerides

How is biodiesel made? continued

• Reaction of transesterification

Base catalyst is a strong base potassium hydroxide which is reacted to methanol to form methoxide.

Other name: methyl alcohol

How is biodiesel made? continued• Heat is also necessary to speed up the reaction• The fatty acid tails are removed from the glycerol

in the oils• They are converted into esters (biodiesel)

Lab Objectives

• Perform a transesterification on a triglyceride (oil) to separate glycerol and fatty acids.

• Use a two phase process to increase conversion of vegetable oil to biodiesel

• Observe the differences in burning properties between biodiesel and vegetable oil.

Safety First

• Gloves• Goggles• Lab apron

CHEMICALS ARE CORROSIVE (CAN CAUSE BURN).CAUTION AROUND HOT PLATESPART OF YOUR GRADE WILL BE ON HOW YOU CAN FOLLOW SAFETY.

Materials

• 2 100 ml beakers • Graduated cylinder 100

ml• graduated cylinder 10 ml• Thermometer• Transfer pipettes• Stirring rod• 12.5 ml Methyl alcohol• timer

Materials shared

• vegetable oil• potassium hydroxide• Electronic balance• Hot plate

Making crude biodiesel – two phase process

• Methoxide preparation: mixing methanol with potassium hydroxide (steps 1 to 7)

• Phase 1 transesterification: react the oil with methoxide while heating to produce biodiesel esters and glycerol (steps 8 to 16)

• Phase 2 transesterification: convert any remaining triglycerides (oil) into biodiesel (steps 17 to 21)

Pre-lab: Procedure reading comprehension

• While reading the procedures 1 to 21:– Put a box around amounts/ grams or volumes/ml of

chemicals. – Underline action verbs/phrase– Put a circle around times and temperature.– Draw the safety triangle symbol whenever

there is safety issue.Example: 1. using an electronic balance, weigh out 0.6 g of potassium hydroxide. Continue shaking in 60 seconds increments. Heat the oil to 55-60°C.

Pre-lab: procedure flowchart

• Take the underlined, boxed, and circled information and put it into a flowchart.

• Add illustrations to your flowchart