Bauxite residue recovery includes mixing a solution of hydrochloric acid (HCL) according to a predetermined concentration, and adding the HCL solution to a quantity of raw red mud recovered from industrial operations as waste material. The highly alkaline property of the bauxite residue, commonly known as red mud is at least partially neutralized from the HCL, and makes the resulting washed red mud more amenable to subsequent uses in various applications in fields such as construction, wastewater treatment, and metal recovery processes. The process recovers washed red mud from the red mud and HCL solution by filtering the raw red mud and HCL solution for generating a stream of leach liquor from the filtrate and the recovered washed red mud from the residue. The neutralized red mud is further treated to extract metals such as calcium, iron, aluminum, silicon, and titanium.

Methods and compositions for improving performance of flocculants in an industrial production process. Methods include pH triggered cross-linking reaction between a flocculating agent, such as dextran, and a composition comprising a boronic acid-containing polymer. The pH trigger can be provided by a fluid having a pH of 8 or more. The production process can be a Bayer Process and the fluid is caustic liquor or slurry in the fluid circuit of the Bayer, wherein the reaction time is reduced over conventional methods and the cross-linked dextran composition effectuates improved flocculation of the trihydrate particles.

Methods and compositions for improving performance of flocculants in an industrial production process. Methods include pH triggered cross-linking reaction between a flocculating agent, such as dextran, and a composition comprising a boronic acid-containing polymer. The pH trigger can be provided by a fluid having a pH of 8 or more. The production process can be a Bayer Process and the fluid is caustic liquor or slurry in the fluid circuit of the Bayer, wherein the reaction time is reduced over conventional methods and the cross-linked dextran composition effectuates improved flocculation of the trihydrate particles.

A Bayer process includes contacting bauxite and calcium fluoride with sodium hydroxide and forming a slurry, with the calcium fluoride may provide at least 1 wt. % of the calcium added to the process, and precipitating alumina from the slurry.

A Bayer process includes contacting bauxite and calcium fluoride with sodium hydroxide and forming a slurry, with the calcium fluoride may provide at least 1 wt. % of the calcium added to the process, and precipitating alumina from the slurry.

The present invention relates to a waste battery treatment method which includes preparing a waste battery including a waste positive electrode which includes an aluminum current collector and a positive electrode active material layer formed on at least one surface of the aluminum current collector, heat treating the waste battery at a temperature of 650° C. or higher in an air atmosphere or oxidizing atmosphere to convert the aluminum current collector into aluminum oxide, and recovering aluminum oxide powder and positive electrode active material powder from the heat-treated waste battery.

The present invention relates to a waste battery treatment method which includes preparing a waste battery including a waste positive electrode which includes an aluminum current collector and a positive electrode active material layer formed on at least one surface of the aluminum current collector, heat treating the waste battery at a temperature of 650° C. or higher in an air atmosphere or oxidizing atmosphere to convert the aluminum current collector into aluminum oxide, and recovering aluminum oxide powder and positive electrode active material powder from the heat-treated waste battery.

A method for controlling the concentration of impurities in Bayer liquors, the method comprising the steps of adding an oxide and/or a hydroxide of a metal other than aluminium to a Bayer liquor with a desired TA; forming a layered double hydroxide; and incorporating at least one impurity in said layered double hydroxide, wherein the impurities are selected from the group comprising phosphorus, vanadium and silicon.

A method for controlling the concentration of impurities in Bayer liquors, the method comprising the steps of adding an oxide and/or a hydroxide of a metal other than aluminium to a Bayer liquor with a desired TA; forming a layered double hydroxide; and incorporating at least one impurity in said layered double hydroxide, wherein the impurities are selected from the group comprising phosphorus, vanadium and silicon.

A method for controlling the concentration of impurities in Bayer liquors, the method comprising the steps of adding an oxide and/or a hydroxide of a metal other than aluminium to a Bayer liquor with a desired TA forming a layered double hydroxide; and incorporating at least one impurity in the layered double hydroxide, wherein the impurities are selected from the group comprising chloride, fluoride, sulfate and TOC.