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Hollow sphere bubble alumina, also known simply as bubble alumina, is a specialized form of alumina (aluminum oxide) characterized by its unique structure, which consists of spherical or bubble-like particles with a central void or hollow space. These hollow spheres are extremely lightweight and have excellent insulating properties, making bubble alumina suitable for various high-temperature and thermal insulation applications. Here are some key characteristics and applications of hollow sphere bubble alumina:


  • Hollow Structure: The primary characteristic of bubble alumina is its hollow or bubble-like structure. Each particle consists of a thin shell of alumina with a central void, which imparts low density and high porosity to the material.

  • Lightweight: Due to its hollow structure, bubble alumina is exceptionally lightweight. It has a low bulk density, making it an ideal material for applications where weight reduction is crucial.

  • High Thermal Insulation: Bubble alumina has excellent thermal insulating properties, making it suitable for use in high-temperature environments. It can withstand extreme temperatures while providing effective thermal insulation.

  • Chemical Inertness: It is chemically inert and resistant to most chemicals, which makes it suitable for use in corrosive environments.


  • Insulation: Bubble alumina is primarily used as a refractory insulation material in various high-temperature applications, such as the lining of industrial furnaces, kilns, and incinerators. Its low thermal conductivity helps to reduce heat loss and improve energy efficiency.

  • Catalyst Supports: In some catalytic processes, bubble alumina is used as a catalyst support due to its high surface area and resistance to chemical reactions.

  • Filler Material: It is used as a lightweight filler material in various composites, coatings, and insulating materials to reduce overall density while maintaining desirable mechanical and thermal properties.

  • High-Temperature Filters: Bubble alumina filters are employed in the filtration of molten metals and alloys. The porous structure allows the filtration of impurities while maintaining the temperature of the molten metal.

  • Hot Gas Filtration: It is used in hot gas filtration systems to remove particulate matter from hot gases in industrial processes.

  • Dielectric Material: Bubble alumina can serve as a dielectric material in electrical insulation applications.

  • Refractory Bricks: It is sometimes incorporated into refractory bricks to enhance their insulating properties and reduce overall weight.

  • Aluminum Production: In the aluminum industry, bubble alumina is used as a lining material for aluminum reduction cells, providing thermal insulation in the production of aluminum.

Hollow sphere bubble alumina is available in various grades and particle sizes to meet the specific requirements of different applications. Its unique combination of lightweight properties and excellent thermal insulation makes it a valuable material in industries where high-temperature processes and insulation are critical.


Hollow Sphere Alumina is a kind of new type thermal insulating material, it is produced by blasting smelted technical grade Aluminium Oxide in electric arc furnace. Crystalline structure is α-Al2O3 micro crystal. It can be made into various shaped refractories with the highest working temperature at 1800°C. The finished refractories have several times of mechanical strength comparing to other common light shaped refractories, while its volume density is only half of Alumina refractories.



Used to produce Hollow Sphere Alumina Bricks for petrochemical gasification burner, carbon black reacting furnace, metallurgical induction furnace and other high or super-high temperature furnace.

Hollow Sphere Bubble Alumina

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