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US 8,540,958 B2Granted
Cascading purification
AssigneeSilicor Materials Inc.
InventorsScott Nichol, Anthony Tummillo, Dan Smith
Life of this patent
Estimating the term…
Abstract
The present invention provides a method of purifying a material using a cascading dissolution and washing process. The dissolution and washing processes can contain single or multiple stages. Water and dissolving chemicals are recycled through the process towards the beginning of the process.
Claims21
A method for increasing the purity of silicon, comprising:
- combining a first silicon-aluminum complex with a first hydrochloric acid solution to allow the first complex to react at least partially with the first hydrochloric acid solution, to provide a first mixture;
- separating the first mixture, to provide a third silicon-aluminum complex and the first hydrochloric acid solution;
- combining the third silicon-aluminum complex with a second hydrochloric acid solution to allow the third complex to react at least partially with the second hydrochloric acid solution, to provide a third mixture, wherein the second hydrochloric acid solution is stronger than the first hydrochloric acid solution;
- separating the third mixture, to provide a first silicon and the second hydrochloric acid solution;
- transferring portions of the second hydrochloric acid solution to the first hydrochloric acid solution to maintain the pH of the first hydrochloric acid solution, the volume of the first hydrochloric acid solution, the specific gravity of the first hydrochloric acid solution, or a combination thereof;
- combining the first silicon with a first rinse solution, to provide a fourth mixture;
- separating the fourth mixture, to provide a wet purified silicon and the first rinse solution;
- drying the wet purified silicon, sufficient to provide a dry purified silicon.
5 more elements
A method for increasing the purity of silicon, comprising:
- combining a first silicon-aluminum complex with a first hydrochloric acid solution to allow the first complex to react at least partially with the first hydrochloric acid solution, to provide a first mixture;
- separating the first mixture, to provide a third silicon-aluminum complex and the first hydrochloric acid solution;
- combining the third silicon-aluminum complex with a second hydrochloric acid solution to allow the third complex to react at least partially with the second hydrochloric acid solution, to provide a third mixture, wherein the second hydrochloric acid solution is stronger than the first hydrochloric acid solution;
- separating the third mixture, to provide a first silicon and the second hydrochloric acid solution;
- combining the first silicon with a first rinse solution, to provide a fourth mixture;
- separating the fourth mixture, to provide a wet purified silicon and the first rinse solution;
- drying the wet purified silicon, sufficient to provide a dry purified silicon;
- removing portions of the first hydrochloric acid solution from the first hydrochloric acid solution to maintain the pH and specific gravity of the first hydrochloric acid solution;
- transferring portions of the second hydrochloric acid solution to the first hydrochloric acid solution to maintain the pH of the first hydrochloric acid solution, the volume of the first hydrochloric acid solution, the specific gravity of the third hydrochloric acid solution, or a combination thereof, wherein the third hydrochloric acid solution is stronger than the first hydrochloric acid solution, and wherein the third hydrochloric acid solution is weaker than the second hydrochloric acid solution;
- adding portions of a bulk hydrochloric acid solution to the second hydrochloric acid solution to maintain the pH of the second hydrochloric acid solution, the volume of the second hydrochloric acid solution, the specific gravity of the second hydrochloric acid solution, or a combination thereof;
- transferring portions of the first rinse solution to the second hydrochloric acid solution to maintain the pH of the second hydrochloric acid solution, the volume of the second hydrochloric acid solution, the specific gravity of the second hydrochloric acid solution, or a combination thereof;
- and
- adding fresh water to the second rinse solution to maintain the volume of the second rinse solution;
- wherein the dry purified silicon comprises approximately 1000-3000 parts per million weight aluminum.
11 more elements
Dependencies are inferred from the claim text.