A reflux apparatus with is set up and filled with 150 mL of anhydrous ethanol, a slow addition of 60 mL of concentrated sulfuric acid is then started and heat at reflux for 1 h, without exceeding 140°C. Subsequently, the mixture is poured into 750 mL of water and the mixture is neutralized with calcium carbonate in the presence of strong stirring. The mixture is heated to 65°C, filtered and washed with some hot water. The filtrate is then basified with sodium carbonate while calcium carbonate drops out, then filtered and washed with some water. The filtrate is concentrated until crystals form on a hot plate, then placed in a refridgerator to cool the mixture down and finally placed in a desiccator to dry the product.
The mixture after reflux
Addition of the calcium carbonate
Concentration of the filtrate
A sample of the product