Several methods are employed in the preparation of catalysts, including:
1. Precipitation: This involves the formation of a solid from a solution. The process typically includes mixing two solutions, leading to the formation of an insoluble solid (precipitate) that is collected, washed, and calcined.
2. Impregnation: A method where a support material is soaked in a solution containing the active component. After drying and calcination, the active component is dispersed on the support's surface.
3. Co-precipitation: Similar to precipitation, but multiple metal precursors are precipitated simultaneously. This method ensures a more uniform distribution of metals.
4. Sol-Gel: Involves the transition of a solution (sol) into a solid (gel). The method allows for precise control over the composition and texture of the catalyst.
5. Hydrothermal Synthesis: Utilizes high-pressure and high-temperature conditions to crystallize materials from aqueous solutions. This method is particularly useful for the synthesis of zeolites and metal-organic frameworks (MOFs).
