Alumina is a valuable raw material used in the production of various products such as adsorbents, abrasives, polishing agents, refractory materials, and aluminum. It is obtained from bauxites through the Bayer process and requires the removal of certain organic compounds to enhance its production. From: Journal of Hazardous Materials, 2020

2014年1月1日 · The structure of these alumina polymorphs differs from that of corundum: they are characterized by cubic close packing of the oxide ions. The product obtained by calcination of boehmite in air is designated as γ-Al 2 O 3 , whereas the product obtained by calcination of bayerite in air is designated as η-Al 2 O 3 .

2004年6月30日 · Most solid phases in natural water contain aluminium oxides. Alumina plays an important role in regulating the composition of soil–water, sediment–water, and other natural water systems [11]. Active alumina, due to its high surface area, mechanical strength and thermal stability has found several applications as an adsorbent and catalyst.

Alumina is defined as aluminum oxide, a white powder produced through the Bayer process which involves the dissolution of bauxite in caustic soda, followed by precipitation and calcination steps. AI generated definition based on: Encyclopedia of Energy, 2004

Alumina is widely utilized in cosmetics as an abrasive, absorbent, and anticaking, bulking, and opacifying agent [114]. Reports conducted by the Personal Care Products Council show that alumina is used in 523 leave-on products, with rinse-off products, eyelid-based products, lipsticks, and skincare products accounting for 40, 84, 87, and 104 ...

2014年5月1日 · The most common “transitional” alumina polymorphs which are applied in the catalysis field are those that may be prepared by thermal decomposition of the oxy-hydroxide boehmite (γ-AlOOH) or of the hydroxide bayerite (α-Al(OH) 3). Differently from corundum, these alumina polymorphs are all based on cubic close packing array of oxide anions.

2025年1月3日 · The sharp increase in corrosion rate with an increasing the alumina addition from 3 wt.% to 10 wt.% is due to the problem mentioned previously, which is the tendency of alumina nanoparticles to agglomerate with increasing their content, which leads to weak binding with matrix and then their fallout, forming cavities and porosities that enhances ...

2024年12月30日 · The SDS-alumina nanoemulsion samples with varying concentrations of alumina NP exhibit increasing G′ (storage modulus) and G″ (loss modulus) value as the angular frequency increases, as evident from Fig. 13. This increase indicates that at higher frequencies, the nanoemulsions display more prominent viscoelastic behavior.

2025年2月1日 · Oxide/oxide composites typically consist of alumina-based fibers embedded in an alumina-based porous matrix [[2], [3], [4]]. Consequently, oxide/oxide composites combine the superior properties of alumina ceramics with quasi-ductile fracture behaviors owning to several crack deflection mechanisms [5, 6]. These composites provide low cost, high ...

2011年1月1日 · The long and increasingly fluid alumina supply lines provide considerable impetus to the further improvement and global standardisation of alumina specifications. This also prompts the need to look at the step-change potential in radically altering the current geographically and resource-inefficient approach to alumina production.