Abstract: 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.

Abstract: This alkali metal and/or alkali earth metal extraction method is superior in terms of cost and allows repeated use of the aqueous solution that extracts alkali metal and/or alkali earth metal from a solid. This method is for extracting alkali metal and/or alkali earth metal from a solid containing an alkali metal and/or alkali earth metal, and involves an elution step in which the solid is added to an amino acid-containing aqueous solution, and the alkali metal and/or alkali earth metal is eluted into the amino acid-containing aqueous solution.

Abstract: This alkali metal and/or alkali earth metal extraction method is superior in terms of cost and allows repeated use of the aqueous solution that extracts alkali metal and/or alkali earth metal from a solid. This method is for extracting alkali metal and/or alkali earth metal from a solid containing an alkali metal and/or alkali earth metal, and involves an elution step in which the solid is added to an amino acid-containing aqueous solution, and the alkali metal and/or alkali earth metal is eluted into the amino acid-containing aqueous solution.

Abstract: 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.

Abstract: Provided is a method of producing an aluminum composite material, the method including: a decalcification treatment step of eluting a calcium oxide component from cement to form decalcified cement having a reduced content of the calcium oxide component; and an aluminum oxide formation step of bringing molten aluminum into contact with the decalcified cement to replace, among metal oxide components contained in the decalcified cement, metal oxide components other than the calcium oxide component, in particular, a silicon dioxide component, with aluminum oxide.

Abstract: Disclosed is a carbon dioxide gas processing apparatus including an oxidization vessel for producing a magnesium oxide by oxidizing magnesium-containing powder in an atmosphere of a gas such as a carbon dioxide gas that contains oxygen as a constituent element thereof, a carbonate production tank that reserves water or a water solution therein and that introduces the magnesium containing oxygen as a constituent element produced in the oxidization vessel, and a carbon dioxide gas supplying means for supplying carbon dioxide gas to the carbonate production tank.