Fine powder mixing in a vibratory ball mill

The applicability of the vibratory ball mill to fine powder mixing is investigated using two model 1:1000 binary systems of microfine salicylic acid sucrose and milled tolbutamide with lactose. Mill performance is evaluated by measuring the extent of mixing relative to a specified standard and by comparing the rate of mixing to the Revolvo-Cube, a conventional tumbling mixer. It is demonstrated that the vibratory ball mill offers distinct advantages in combining the two unit operations of milling and mixing by rapidly producing highly homogeneous fine powder mixtures. Finally, the mechanism of comminution and mixing in the vibratory ball mill at the particulate level is examined.