[foxthreefour]

If a a solution of a hydrochloride salt in water also contained residual DCM as an azeotrope, how would this be expected to influence crystallisation? I feel like its increasing the amount of nucleation sites and the crystal quality is being affected.

Any reading material that contains the topic would be appreciated.

[wildfyr]

It would prevent crystallization by being an impurity/lowering the melting point of the solid.

[jeffmoonchop]

If you are seeing more nucleation sites it means the solution is more supersaturated. Its possible the salt is less soluble in DCM and more soluble in water. So the DCM is acting as an antisolvent. In general if you want less nucleation sites and larger particles, you need to reduce supersaturation, slow things down. Try adding more water to see how it affects particle size.