The crude dyestuff is distilled to get 1/3rd of the
using the Soxhlet apparatus at 70°C for 3hrs. In
this process ethanol is recovered and the concentrated
dye is obtained. The solution is kept overnight at room
temperature for precipitation. The precipitation in
ethanol water is obtained by decanting the solution. The
obtained particles are dried in the oven overnight at
60°C. Water was added in the Soxhlet apparatus. By
addition of water, the boiling points of the compounds
are lowered, allowing them to evaporate at lower
temperatures.
Whatever the concentration of solvent may be, the
purification process remains the same.