Processes for treating fly ashes
AssigneeOrbite Technologies Inc.
InventorsRichard Boudreault, Joël Fournier, Denis Primeau
Life of this patent
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Abstract
There are provided processes for treating fly ash. For example, the processes can comprise leaching fly ash with HCl so as to obtain a leachate comprising aluminum ions and a solid, and separating the solid from the leachate; reacting the leachate with HCl so as to obtain a liquid and a precipitate comprising the aluminum ions in the form of AlCl3, and separating the precipitate from the liquid; and heating the precipitate under conditions effective for converting AlCl3 into Al2O3 and optionally recovering gaseous HCl so-produced.
Claims20
A process for treating raw fly ash, said process comprising:
- optionally a pre-leaching treatment that consists of reducing the particle size of said raw fly ash;
- leaching said raw fly ash with HCl so as to obtain a leachate comprising aluminum ions and iron ions and a solid, and separating said solid from said leachate;
- reacting said leachate with HCl so as to obtain a liquid comprising iron ions and a precipitate comprising said aluminum ions in the form of AlCl3, and separating said precipitate from said liquid;
- and
- heating said precipitate under conditions effective for converting AlCl3 into Al2O3 and optionally recovering gaseous HCl so-produced.
A process for preparing aluminum, said process comprising :
- optionally a pre-leaching treatment that consists of reducing the particle size of raw fly ash;
- leaching said raw fly ash with HCl so as to obtain a leachate comprising aluminum ions and iron ions and a solid, and separating said solid from said leachate;
- reacting said leachate with HCl so as to obtain a liquid comprising iron ions and a precipitate comprising said aluminum ions in the form of AlCl3, and separating said precipitate from said liquid;
- heating said precipitate under conditions effective for converting AlCl3 into Al2O3 and optionally recovering gaseous HCl so-produced;
- and
- converting said Al2O3 into aluminum.
Dependencies are inferred from the claim text.