Lactose powder flowability enhancement by atmospheric pressure plasma treatment

Abstract

For the first time, an atmospheric‐pressure plasma process is presented that enables continuous flowability improvement of cohesive, temperature‐sensitive, and fine‐grained powder. For this, an atmospheric pressure dielectric barrier discharge operating with argon and oxygen is used to dissociate HMDSO and form nanoparticles. The nanoparticles are directly deposited on the surface of cohesive lactose powder. These nanoparticles decrease the distance‐dependent attractive van der Waals forces in between the lactose particles and therefore, improve its flowability. Flow factor and powder surface are investigated using a ring‐shear tester and scanning electron microscopy, respectively. High flow factors are found when the total flow rate and HMDSO concentration trigger the formation of large nanoparticle quantities and agglomerates. Repeating the plasma process up to three times improves flowability from the cohesive regime to the easy flowing regime.