1. Filtration: Removing solid impurities from the feedstock. 2. Distillation: Separating components based on boiling points to purify the feedstock. 3. Grinding and Milling: Reducing particle size to increase surface area for more effective catalysis. 4. Calcination: Heating catalysts to high temperatures in an inert atmosphere to remove volatile substances. 5. Impregnation: Adding active catalytic species onto a support material.
