A process for the production of potassium sulphate by conversion of potassium chloride and sulphuric acid using a muffle furnace, said furnace comprising a reaction chamber and a combustion chamber, wherein in the reaction chamber potassium chloride (KCI) and potassium hydrogen sulfate (KHSO.sub.4) are reacted to form potassium sulphate while supplying heat to the reaction chamber from the combustion chamber, wherein the combustion chamber has at least a pair of regenerative burners and wherein the process comprises the steps of alternatingly causing one of the regenerative burners to perform a combustion operation in the combustion chamber to heat the reaction chamber and another of the regenerative burners to perform a heat-regenerating operation in a regenerator, wherein the pressure in the combustion chamber is kept at a pressure of between 0.2 and 3 mbarg.

Lithium is an essential element for high-energy rechargeable batteries and other technologies. Disclosed herein are systems and processes for the extraction of lithium from liquid resources. The aforementioned systems and processes utilize ion exchange materials that selectively and reversibly bind lithium. The performance of the ion exchange materials is enhanced by the use of a chemical additive.

There are provided processes for treating red mud. For example, the processes can comprise leaching red mud with HCl so as to obtain a leachate comprising ions of a first metal (for example aluminum) and a solid, and separating said solid from said leachate. Several other metals can be extracted from the leachate (Fe, Ni, Co, Mg, rare earth elements, rare metals, etc.). Various other components can be extracted from solid such as TiO.sub.2, SiO.sub.2 etc.

There are provided processes for treating red mud. For example, the processes can comprise leaching red mud with HCl so as to obtain a leachate comprising ions of a first metal (for example aluminum) and a solid, and separating said solid from said leachate. Several other metals can be extracted from the leachate (Fe, Ni, Co, Mg, rare earth elements, rare metals, etc.). Various other components can be extracted from solid such as TiO.sub.2, SiO.sub.2 etc.

The present invention relates to a furnace suitable for the production of sulfate salts, in particular potassium sulfate, from sulfuric acid and an alkali metal chloride and/or an alkaline earth metal chloride wherein heating is supplied by electrical resistors. The furnace is more energy-efficient and environmentally-friendly than furnaces relying on fossil fuels, and enables a significantly increased control over heat distribution and temperature profiles therewithin. The invention further relates to methods for the production of sulfate salts.

The present invention relates to a furnace suitable for the production of sulfate salts, in particular potassium sulfate, from sulfuric acid and an alkali metal chloride and/or an alkaline earth metal chloride wherein heating is supplied by electrical resistors. The furnace is more energy-efficient and environmentally-friendly than furnaces relying on fossil fuels, and enables a significantly increased control over heat distribution and temperature profiles therewithin. The invention further relates to methods for the production of sulfate salts.

A process for battery chemical production, where a sodium sulfate stream is treated with an ion exchange process to provide potassium sulfate and sodium chloride. The sodium chloride may be treated with a chlor-alkali to produce sodium hydroxide for use upstream in the battery chemical production process.

A process for battery chemical production, where a sodium sulfate stream is treated with an ion exchange process to provide potassium sulfate and sodium chloride. The sodium chloride may be treated with a chlor-alkali to produce sodium hydroxide for use upstream in the battery chemical production process.