Unformatted text preview: in aspirin manufacture: weighing, mixing, filtration and drying. These followed by the purification, dry screening, compression, testing, bottling, packaging and quality control. Now the manufacture of aspirin is highly automated and in most pharmaceutical companies, completely computerized. OBJECTIVE To illustrate the preparation of aspirin drug CHEMICAL AND EQUIPMENT CHEMICALS
2g Salicylic acid
3ml Acetic Anhydride (density = 1.08
10 ml Ethanol
Conc. Sulphuric Acid
1% Ferric Chloride EQUIPMENT
30ml Large test tube
Filter papers If any salicylic acid remains, its presence can be detected with 1% iron (III) chloride solution. The iron (III) gives a violet color with any molecule having a phenol group. Thus a pure sample of aspirin will not give a purple color with 1% iron (III) chloride solution. PROCEDURE PREPARATION OF CRUDE ASPIRIN 1. Weigh about 2.0g of salicylic acid up to 4 decimal, place in a 25‐ml dry test tube and add carefully 3ml of acetic anhydride. 2. Add 4 drops of concentrated sulfuric acid into the above mixture of the test tube. 3. Mix the reagents by gentle shaking and put the test tube in a beaker of water pre‐warmed to (80 – 90) °C (just below boiling) and l...
View Full Document
This document was uploaded on 03/04/2014.
- Spring '14