Lab and pilot plant tours Scaling up

1. Lab and pilot plant toursScaling up www.abpischools.org.uk

3. Pear shaped flask • Bunsen burner • Reflux condenser • Vacuum filtration Preparation of Aspirin (typical A level procedure)

4. Preparation of Aspirin (typical A level procedure) 1. Weigh out 2g of 2-hydroxybenzoic acid and place it in a pear shaped flask. (The starting material is a fluffy irritant white solid.) 2. Add 4.0cm3 of ethanoic anhydride. (A colourless liquid with a pungent smell.) 3. The reaction mixture will get slightly warm so cool it by swirling the flask under running water. 4. When it is cool, add two anti-bumping granules. 5. Heat under reflux for 30 minutes. 6. Cool the mixture. 7. Pour into 100cm3 of cold water containing 10cm3 of dilute sulphuric acid. Stir and allow the resulting suspension to stand for 15 minutes. 8. Filter off the crystals that form. Dry and weigh the product.

5. The chemistry used to make aspirin ethanoic anhydride 2-hydroxybenzoic acid aspirin

6. Preparation of Aspirin (typical A level procedure) 1. Weigh out 2g of 2-hydroxybenzoic acid and place it in a pear shaped flask. (The starting material is a fluffy irritant white solid.) How would you do this for 20kg - 10,000 times the scale?

7. Preparation of Aspirin (typical A level procedure) 1. Weigh out 2g [20kg] of 2-hydroxybenzoic acid and place it in a pear shaped flask. (The starting material is an irritant fluffy white solid.)

8. Preparation of Aspirin (typical A level procedure) Temperature probe 2. Add 4.0cm3 [40 litres] of ethanoic anhydride. (A colourless liquid with a pungent smell).

9. Preparation of Aspirin (typical A level procedure) 2. Add 4.0cm3 [40 litres] of ethanoic anhydride. (A colourless liquid with a pungent smell).

10. Preparation of Aspirin (typical A level procedure) 3. The reaction mixture will get slightly warm so cool it by swirling the flask under running water.

11. Preparation of Aspirin (typical A level procedure) 3. The reaction mixture will get slightly warm so cool it by swirling the flask under running water.

12. Preparation of Aspirin (typical A level procedure) 3. The reaction mixture will get slightly warm so cool it by swirling the flask under running water.

13. Preparation of Aspirin (typical A level procedure) 4. When it is cool, add two anti-bumping granules. 5. Heat under reflux for 30 minutes.

14. Heat under reflux for 30 minutes 140 120 °C 100 80 60 40 20 60 90 120 150 180 30 Time in minutes

15. Preparation of Aspirin (typical A level procedure) 5. Heat under reflux for 30 minutes. Condenser The maximum transfer of heat from the fluid in the jacket to the reaction mixture is 2° per minute

16. Heat under reflux for 30 minutes 140 120 °C 100 80 60 40 20 60 90 120 150 180 30 Time in minutes

17. Preparation of Aspirin (typical A level procedure) Condenser 6. Cool the mixture. 7. Pour into 100cm3 [1000 litres] of cold water containing 10cm3 [100 litres] of dilute sulphuric acid. Stir and allow the resulting suspension to stand for 15 minutes. 8. Filter off the crystals that form. Dry and weigh the product.

18. Preparation of Aspirin (typical A level procedure) 8. Filter off the crystals that form. Dry and weigh the product.

19. Filter off the crystals that form

20. Dry and weigh the product