A method for producing a concentrated aqueous sodium hydroxide solution from a purge stream deriving from a sodium carbonate, or sesquicarbonate, or wegsheiderite crystallizer, or sodium bicarbonate crystallizer, said purge stream comprising sodium carbonate and/or bicarbonate, and at least 1% of sodium chloride or sodium sulfate and a soluble impurity from an ore deposit comprising at least one of the following elements: As, Ba, B, Ca, Co, K, Li, Mo, P, Pb, Se, Sn, Sr, Te, Tl, Ti, V, and W, to be purified, the method comprising: causticizing at least 50 mol. % of the sodium carbonate into a caustic solution and into a calcium carbonate mud with lime and water; separating the mud from the caustic solution; concentrating the caustic solution by removing part of the water to obtain a concentrated caustic solution comprising at least 25% NaOH, and a crystallized solid comprising sodium carbonate and sodium chloride and/or sulfate; and separating the crystallized solid from the concentrated caustic solution, said crystallized solid to be disposed of or to be further valorized.

The present disclosure provides stabilized hematoxylin formulations having a pH of less than 2.4. The present disclosure also provides methods of using such stabilized hematoxylin formulations to stain biological samples.

The present disclosure provides stabilized hematoxylin formulations having a pH of less than 2.4. The present disclosure also provides methods of using such stabilized hematoxylin formulations to stain biological samples.

The present disclosure relates to processes for recovering rare earth elements from an aluminum-bearing material. The processes can comprise leaching the aluminum-bearing material with an acid so as to obtain a leachate comprising at least one aluminum ion, at least one iron ion, at least one rare earth element, and a solid, and separating the leachate from the solid. The processes can also comprise substantially selectively removing at least one of the at least one aluminum ion and the at least one iron ion from the leachate and optionally obtaining a precipitate. The processes can also comprise substantially selectively removing the at least one rare earth element from the leachate and/or the precipitate.

The present disclosure relates to processes for recovering rare earth elements from an aluminum-bearing material. The processes can comprise leaching the aluminum-bearing material with an acid so as to obtain a leachate comprising at least one aluminum ion, at least one iron ion, at least one rare earth element, and a solid, and separating the leachate from the solid. The processes can also comprise substantially selectively removing at least one of the at least one aluminum ion and the at least one iron ion from the leachate and optionally obtaining a precipitate. The processes can also comprise substantially selectively removing the at least one rare earth element from the leachate and/or the precipitate.

A pre-sodium treated positive electrode material for copper-zinc-based sodium ion battery and method of preparing the same are provided. The method includes the steps of obtaining a mixed solution containing copper-zinc-based elements through wet pre-sodium first, then conducting spray drying of the mixed solution containing copper-zinc-based elements to obtain precursor powder of positive electrode material for copper-zinc-based sodium ion battery, and then mixing the precursor powder with a sodium source for sintering, coating and crushing to obtain positive electrode material for copper-zinc-based sodium ion battery. The pre-sodium treated positive electrode material for copper-zinc-based sodium ion battery thus prepared introduces weakly oxidizing zinc and nickel elements on the basis of the copper-based material, reducing the use of highly oxidizing copper and iron elements. After being prepared into a battery, the oxidation of metal ions in the electrochemical environment is reduced overall.

The present disclosure provides stabilized hematoxylin formulations having a pH of less than 2.4. In general, the stabilized hematoxylin formulations comprise a solvent, a hematoxylin dye, and an acid. The present disclosure also provides methods of using such stabilized hematoxylin formulations to stain biological samples. The present disclosure also provides for methods of readjusting the pH of a stabilized hematoxylin formulation to provide a hematoxylin staining solution.

The present disclosure provides stabilized hematoxylin formulations having a pH of less than 2.4. The present disclosure also provides methods of using such stabilized hematoxylin formulations to stain biological samples.