Lactose monohydrate → (+)-Lactose

Participants

Reaction Conditions

Reaction Steps

A solution of lactose monohydrate in water having a concentration of between about 5% and about 15% w/w is poured into stainless steel pans prechilled to about -35° C. The freeze dryer shelf temperature is maintained at -40° C. until the solution is frozen. The drying chamber is evacuated and primary drying is conducted at a temperature below -31.5° C. (pan contents). The temperature of the pan contents (frozen solution) is maintained at a temperature of between about -33° C. and about -38° C. by control of the shelf temperature at between about -15° C. and about -18° C. and a chamber pressure of between about 60 microns and 70 microns. When ice sublimation is complete as indicated by the temperature readings of the pan contents, secondary drying is conducted at a shelf temperature of about 25° C. for 15 h and at about 40° C. for 3 h. The amorphous lactose obtained has a water content of between about 1% and about 2%.

Provenance & Evidence