Low temperature reduction of metal oxides
AssigneeKinaltek Pty. Ltd.
InventorsJawad Haidar, Bilal Khan, Rajan Gnanarajan
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Abstract
Disclosed herein is a method for reducing a metal oxide in a metal oxide containing precursor. The method comprises providing a reaction mixture comprising the metal oxide containing precursor and an aluminium reductant; heating the reaction mixture in the presence of solid or gaseous aluminium chloride to a temperature at which reactions that result in the metal oxide being reduced are initiated; controlling reaction conditions whereby the reaction mixture is prevented from reaching a temperature at which thermal runaway can occur; and isolating reaction products that include reduced metal oxide.
Claims13
A method for producing a powder comprising silicon, the method comprising:
- providing a reaction mixture comprising a silicon oxide containing precursor and an aluminum reductant;
- heating the reaction mixture at atmospheric pressure in the presence of gaseous aluminum chloride or a mixture of solid and gaseous aluminum chloride to a temperature of between 300° C. and 600° C., whereby reactions that result in the silicon oxide being reduced are initiated, the amount of the aluminum chloride being between 1 wt % and 500 wt % of the weight of the silicon oxide containing precursor;
- controlling reaction conditions to maintain the temperature below 650° C., whereby the reaction mixture is prevented from reaching a temperature at which thermal runaway can occur and whereby the formation of aluminium oxychloride as a by-product is favored over aluminum oxide;
- and
- washing products of the reaction in dilute acid to isolate the silicon powder.
A method for producing a powder comprising silicon, the method comprising:
- feeding a silicon oxide containing precursor and an aluminum reductant into a reaction vessel at atmospheric pressure and at a temperature of between 300° C. and 600° C., in the presence of gaseous aluminum chloride or a mixture of solid and gaseous aluminum chloride;
- mixing the reactants together and in the presence of reaction products that form;
- controlling a feed rate of the silicon oxide containing precursor and the aluminum reductant into the reaction vessel such that the temperature in the reaction vessel does not exceed 650° C.;
- and
- washing the reaction products in dilute acid to remove aluminum oxychloride by-product and isolate the silicon powder.
Dependencies are inferred from the claim text.