A process for producing alumina and a lithium salt comprising the steps of: (a) calcining an alpha spodumene ore or concentrate to produce beta spodumene; and (b) (I) leaching beta spodumene from the calcining step (a) with an alkaline solution under pressure; or (II) sulphating beta spodumene with at least sodium sulphate and leaching said sulphated beta spodumene to produce a lithium containing solution and a zeolitic residue. The lithium containing solution is treated to provide a purified lithium salt and said zeolitic residue is treated to provide high purity alumina.

A readily soluble alumina and a method for preparing the same involve: mixing an aluminum hydroxide and a sodium aluminate solution to obtain an aluminum hydroxide slurry; performing a high-temperature reaction on the aluminum hydroxide slurry to obtain an alumina hydrate; and performing a low-temperature calcination on the alumina hydrate to obtain a readily soluble alumina.

A readily soluble alumina and a method for preparing the same involve: mixing an aluminum hydroxide and a sodium aluminate solution to obtain an aluminum hydroxide slurry; performing a high-temperature reaction on the aluminum hydroxide slurry to obtain an alumina hydrate; and performing a low-temperature calcination on the alumina hydrate to obtain a readily soluble alumina.

This invention refers to a technically and economically viable process for recovery of relevant metallic and non-metallic contents from mining residues, particularly the bauxite residue, using it in its integral form. Such a process route uses energy from microwaves, assisted leaching and logic sequencing of steps that allow a technically and economically viable removal of components from the bauxite residue, particularly the residue from the Bayer process. The invention also refers to a microwave reactor that is appropriate for performing the above-mentioned process, as well as to a method for heating a mining product.

This invention refers to a technically and economically viable process for recovery of relevant metallic and non-metallic contents from mining residues, particularly the bauxite residue, using it in its integral form. Such a process route uses energy from microwaves, assisted leaching and logic sequencing of steps that allow a technically and economically viable removal of components from the bauxite residue, particularly the residue from the Bayer process. The invention also refers to a microwave reactor that is appropriate for performing the above-mentioned process, as well as to a method for heating a mining product.

The present invention refers to a process for the preparation of a high surface area nanoparticulate alpha alumina.

The present invention refers to a process for the preparation of a high surface area nanoparticulate alpha alumina.