The present invention provides an alkali metal and/or alkali earth metal extraction method that has excellent extraction efficiency and allows repeated use of an aqueous solution that extracts an alkali metal and/or alkali earth metal from a solid. The alkali metal and/or alkali earth metal extraction method is a method for extracting an alkali metal and/or alkali earth metal from a solid containing the alkali metal and/or alkali earth metal, the method including an elution step in which the solid is added to a neutral amino acid-containing aqueous solution or an amino acid-containing mixed aqueous solution produced by mixing a pH adjusting agent with an aqueous solution containing at least one of a neutral amino acid, an acidic amino acid and a basic amino acid so as to elute the alkali metal and/or alkali earth metal in the neutral amino acid-containing aqueous solution or the amino acid-containing mixed aqueous solution.

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.

A cation adsorbent of an embodiment includes tungsten oxide particles having a BET specific surface area in a range of 0.82 m.sup.2/g or more and 820 m.sup.2/g or less. The cation adsorbent is added to a solution to be treated containing cations being recovery objects, and the cation adsorbent adsorbing the cations is precipitated. The generated precipitate is separated from the solution to recover the cations.

A cation adsorbent of an embodiment includes tungsten oxide particles having a BET specific surface area in a range of 0.82 m.sup.2/g or more and 820 m.sup.2/g or less. The cation adsorbent is added to a solution to be treated containing cations being recovery objects, and the cation adsorbent adsorbing the cations is precipitated. The generated precipitate is separated from the solution to recover the cations.

A method for extracting an alkali metal element comprises contacting a sample comprising a first alkali metal salt with a first lixiviant, the first lixiviant comprising a first amine cation and a first counterion, wherein the first alkali metal salt comprises a first alkali metal element, and wherein the first lixiviant is selected to react selectively with the first alkali metal salt. The method forms a depleted sample and a first supernatant comprising a first uncharged or charged amine, and a first soluble complex comprising a cation of the first alkali metal element and the first counterion. The method further transfers the first alkali metal element cation from the first supernatant, and regenerates the first amine cation by the addition of a first precipitant or salt forming agent.

A method for selectively extracting sedimentogenic strontium and barium from terrigenous elastic sediments to reflect the difference between marine and continental sedimentary environments is disclosed. The method comprises collecting loose sediment, removing visible biogenic clasts, baking the sample and crushing the sample to a grain size no larger than 100-mesh. The method further comprises weighing the sample, reacting the sample in acetic acid or acetic acid-acetate solution, stirring or oscillating the sample at room temperature and normal pressure, separating the solid and liquid after reaction and analyzing strontium and barium in the supernatant. The gained Sr/Ba ratio of the supernatant reflects whether the sediments were deposited in a marine or a continental sedimentary environment.

A method for selectively extracting sedimentogenic strontium and barium from terrigenous elastic sediments to reflect the difference between marine and continental sedimentary environments is disclosed. The method comprises collecting loose sediment, removing visible biogenic clasts, baking the sample and crushing the sample to a grain size no larger than 100-mesh. The method further comprises weighing the sample, reacting the sample in acetic acid or acetic acid-acetate solution, stirring or oscillating the sample at room temperature and normal pressure, separating the solid and liquid after reaction and analyzing strontium and barium in the supernatant. The gained Sr/Ba ratio of the supernatant reflects whether the sediments were deposited in a marine or a continental sedimentary environment.

A method for in situ solution mining of a mineral from an underground evaporite stratum using a set of wells in fluid communication with at least one mineral cavity with some wells operated in solvent injection mode and other wells operated in brine production mode and optionally with some inactive wells, comprising switching the operation mode of one or more wells. The evaporite mineral preferably comprises trona. The at least one cavity may be formed by directionally drilled uncased boreholes or by lithological displacement of the evaporite stratum at a weak interface with an underlying insoluble stratum by application of a lifting hydraulic pressure to create an interfacial gap. The extracted brine can be processed to make valuable products such as soda ash and/or any derivatives thereof. This method can provide more uniform dissolution of mineral in the cavity, minimize flow channeling, minimize sodium bicarbonate blinding for solution mining of incongruent trona ore, and/or may avoid uneven deposit of insolubles.

A method for in situ solution mining of a mineral from an underground evaporite stratum using a set of wells in fluid communication with at least one mineral cavity with some wells operated in solvent injection mode and other wells operated in brine production mode and optionally with some inactive wells, comprising switching the operation mode of one or more wells. The evaporite mineral preferably comprises trona. The at least one cavity may be formed by directionally drilled uncased boreholes or by lithological displacement of the evaporite stratum at a weak interface with an underlying insoluble stratum by application of a lifting hydraulic pressure to create an interfacial gap. The extracted brine can be processed to make valuable products such as soda ash and/or any derivatives thereof. This method can provide more uniform dissolution of mineral in the cavity, minimize flow channeling, minimize sodium bicarbonate blinding for solution mining of incongruent trona ore, and/or may avoid uneven deposit of insolubles.