Alumina is an important industrial raw material, widely used in ceramics, pharmaceuticals, adsorbent materials, catalysts, and catalyst carriers. To date, at least eight different forms of alumina have been identified, each with distinct macrostructural properties. Compared to other forms, "activated alumina" is the most widely used desiccant, defluorinating agent, catalyst, and catalyst carrier in industrial production due to its advantages such as adjustable pore structure, large specific surface area, excellent adsorption performance, acidity, and good thermal stability. Specific applications include desiccants for air compressors, defluorinating agents, specialized production, catalyst carriers, deep drying and dehydration, and catalyst carriers.