The present disclosure generally relates to processes for the reduction of transition metals using alkali metals to produce reduced transition metals.

The present disclosure generally relates to processes for the reduction of transition metals using alkali metals to produce reduced transition metals.

Systems and methods are provided for processing metal sulfate compounds and sequestering CO.sub.2. These systems and processes involve one or more electrochemical cells for producing an alkali-containing catholyte and involve a CO.sub.2 absorption reactor operatively connected to the electrochemical cell and to a CO.sub.2 source. The CO.sub.2 absorption reactor receives the alkali-containing catholyte and CO.sub.2 gas for forming an alkaline carbonate solution. The alkaline carbonate solution is directed to a vessel where it reacts with an acidic sulfate solution comprising metal ions resulting in precipitation of solid metal carbonate compounds. The acidic sulfate solution may comprise sulfide leachates from acid mine drainage, sulfide mine tailings and/or reacted pyrite concentrate. The acidic sulfate solution may be circulated through an optional SO.sub.2 reduction reactor prior to reaction in the vessel. The SO.sub.2 reduction reactor reduces trivalent metal compounds present in the acidic sulfate solution to divalent metal compounds.

Systems and methods are provided for processing metal sulfate compounds and sequestering CO.sub.2. These systems and processes involve one or more electrochemical cells for producing an alkali-containing catholyte and involve a CO.sub.2 absorption reactor operatively connected to the electrochemical cell and to a CO.sub.2 source. The CO.sub.2 absorption reactor receives the alkali-containing catholyte and CO.sub.2 gas for forming an alkaline carbonate solution. The alkaline carbonate solution is directed to a vessel where it reacts with an acidic sulfate solution comprising metal ions resulting in precipitation of solid metal carbonate compounds. The acidic sulfate solution may comprise sulfide leachates from acid mine drainage, sulfide mine tailings and/or reacted pyrite concentrate. The acidic sulfate solution may be circulated through an optional SO.sub.2 reduction reactor prior to reaction in the vessel. The SO.sub.2 reduction reactor reduces trivalent metal compounds present in the acidic sulfate solution to divalent metal compounds.

This invention relates to treated geothermal brine compositions containing reduced concentrations of iron, silica, and manganese compared to the untreated brines. Exemplary compositions contain a concentration of manganese less than 10 mg/kg, a concentration of silica ranging from less than 10 mg/kg, and a concentration of iron less than 10 mg/kg, and the treated geothermal brine is derived from a Salton Sea geothermal reservoir.

This invention relates to treated geothermal brine compositions containing reduced concentrations of iron, silica, and manganese compared to the untreated brines. Exemplary compositions contain a concentration of manganese less than 10 mg/kg, a concentration of silica ranging from less than 10 mg/kg, and a concentration of iron less than 10 mg/kg, and the treated geothermal brine is derived from a Salton Sea geothermal reservoir.

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.

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.

The present disclosure provides a polymetallic-ore beneficiation and separation reagent, a preparation method therefor and use thereof. The preparation method for a polymetallic-ore beneficiation and separation reagent, includes following steps: (1) mixing a substance A, caustic soda, soda ash and sodium polysulfide, and then heating the same and performing a catalytic reaction, to render an intermediate product B, wherein the substance A includes one or more of urea, glycine, urea peroxide, ammonium cyanate and isocyanic acid; and (2) mixing the intermediate product B with trichloroisocyanuric acid, dichloroisocyanuric acid and 2-amino-3-(4-imidazolyl)propanoic acid, to render the polymetallic-ore beneficiation and separation reagent.

The present disclosure provides a polymetallic-ore beneficiation and separation reagent, a preparation method therefor and use thereof. The preparation method for a polymetallic-ore beneficiation and separation reagent, includes following steps: (1) mixing a substance A, caustic soda, soda ash and sodium polysulfide, and then heating the same and performing a catalytic reaction, to render an intermediate product B, wherein the substance A includes one or more of urea, glycine, urea peroxide, ammonium cyanate and isocyanic acid; and (2) mixing the intermediate product B with trichloroisocyanuric acid, dichloroisocyanuric acid and 2-amino-3-(4-imidazolyl)propanoic acid, to render the polymetallic-ore beneficiation and separation reagent.