Particle Breakage Using Wet Mill, Ultrasonic, and Hydrodynamic Cavitation

Abstract

In-line fluidic devices and mills are often used for controlling crystal size distribution during crystallization. In this work, we investigated the breakage of organic crystals in three particle breakage devices. Paracetamol was selected as a model API (active pharmaceutical ingredient). In order to focus the investigation on particle breakage, we have used paracetamol suspended in its saturated solution and eliminated possible changes in particle size because of crystallization or dissolution. Particle breakage in a wet mill (WM), which is one of the commonly used particle breakage devices, is compared with the two cavitation-based devices: one based on ultrasonic or acoustic cavitation (AC) and the other based on hydrodynamic cavitation (HC). The particle size distributions (PSD) were measured by using laser diffraction. Kapur function analysis was used to study the effect of various conditions, such as rotational speed, intensity, or pressure drop, on the specific breakage rates and breakage mechanisms. The vortexbased HC device used in this work generated more fine particles than any other technique at a similar power consumption.

Pre-Treatment of Spent Coffee Grounds Using Hydrodynamic Cavitation

“…The HC process breaks down the solid particles present in the system into smaller ones. The higher the pressure accompanying the HC process, the smaller the particles obtained which is in agreement with the literature [49].…”

Gravity as a Knob for Tuning Particle Size Distributions of Small Molecules

“…Thus, the evolution of the CWCLD in the process is a representation of the evolution of coarser particles in the process. If breakage had been the only dominating mechanism, the larger particles would have broken down into smaller particles. , Breakage is characterized by a shift of the mode of the CWCLD to the left with time, which is not observed in Figure g. In contrast, during secondary nucleation, the generation of many fine particles increases the total counts/s in the LWCLD with time.…”