Dynamic absorption efficiency of paracetamol powder in microwave drying

In microwave drying technology, research into the dynamic absorbing properties of the powder is indispensable. In this study, the reflection loss coefficient of paracetamol powder under different temperature, water content, and thickness was calculated based on the principle of electromagnetic wave transmission. The results show that the absorption performance of powder fluctuates dynamically with a series of absorption peaks, and the position of the absorption peak shifts toward the smaller thickness direction as the water content increases or the temperature rises. Because of the influence of the powder thickness on absorbing efficiency, the powder thickness should be adjusted in real time to increase drying efficiency. This study provides the thickness range for which the absorption performance of paracetamol powder under different conditions is over 99%. This study is of great significance for understanding the drying mechanism and optimizing process parameters for microwave drying of pharmaceutical powder.