Question

How does using too much solvent during crystallization affect percent recovery?

Answer 1

During the crystallization process, the solvent used for the recrystallization should be minimum, so as to form the saturated solution of the compound to be crystallized. Then, there will be a maximum recovery of the compound.

But if you use too much (very high) amount of solvent during crystallization, the solvent has to evaporate first to obtain the precipitate or crystals of the pure compound. In this case, there will always be a crystallization of a small amount of product. You need to collect the crystals and filter the mother liquor several times, as a result, there will be a loss of compound, which will severely affect its percent recovery.