Alumina, or aluminum oxide grains are used by Refractron to manufacture many of its porous ceramic products. Alumina is chosen because of its chemical durability, strength and refractory properties.
Refractron customizes the grain size, bond chemistry, forming method and firing conditions to meet the requirements of each application. The chemistry of the specific alumina materials, and processing can impact the color of the material, which is why porous alumina can be black, grey, tan or white.
Porous ceramics from Refractron are resistant to most acids, except hydrofluoric and phosphoric. They also demonstrate excellent resistance to organic solvents, as well as alkaline solutions up to ~50ºC (122°F). Our rugged alumina porous ceramics are “green”, long lasting solutions that are not only mechanically strong (MOR 26 MPa), but inert and cleanable.
Regular cleaning can restore porous alumina products to like new conditions. Unlike many polymeric based materials alumina ceramics can be subjected to aggressive cleaning treatments including high temperatures and corrosive chemicals without destroying them.
Refractron’s porous alumina is the material of choice for fine bubble diffusers, as they are hydrophilic. For a given pore size, alumina diffusers produce finer bubbles that lead to better gas transfer efficiency than rubber diffusers or membranes.
Porous alumina products are used in a variety of applications up to 800°C to replace metal or as an alternative to plastic, polymeric or fabric. Refractron’s alumina products can be generically categorized as a porous ceramic wick, filter, sparger or fine bubble diffuser. Applications include:
|De chlorination||Emissions monitoring|
|Sour gas & water treatment||Water/beverage filtration||Printing|
|De watering minerals|