Comparison of Milling Processes: Ball Mill Versus Air Classifying Mill

Abstract

A study was initiated to compare the milling process and equivalence of mills for milling a fibrous material. In this study, milling processes using either a ball mill (Abbe Model Number 2) or an air classifying mill (Mikro ACM 10) were compared. Samples from both processes were evaluated by appropriate physical and chemical analyses such as particle size, surface area, densities, and potency. The particle size distribution and surface area analysis showed equivalence between the two milling processes. Scanning electron micrographs (SEM) showed that the samples had similar morphology. The potency of samples obtained from either of the milling processes was not affected by differences in the milling processes. In addition, results of milled samples that were subsequently granulated and compressed into tablets showed no difference in assay, content uniformity or disintegration time. Based on these results, it is concluded that the ball mill and the air classifying mill produce material that is equivalent in terms of physical and chemical properties, and therefore the processes of milling are interchangeable.