Abstract: A method for producing an alkali metal hydroxide, comprises providing an electrolytic cell that includes at least one membrane having ceramic material configured to selectively transport alkali metal ions. The method includes introducing a first solution comprising an alkali metal hydroxide solution into a catholyte compartment such that said first solution is in communication with the membrane and a cathode. A second solution comprising at least one alkali metal salt and one or more monovalent, divalent, or multivalent metal salts is introduced into an anolyte compartment such that said second solution is in communication with the membrane and an anode. The method includes applying an electric potential to the electrolytic cell such that alkali metal ions pass through the membrane and are available to undertake a chemical reaction with hydroxyl ions in the catholyte compartment to form alkali metal hydroxide.

Abstract: Metal ion conducting ceramic materials are disclosed having characteristics of high ion conductivity for certain alkali and monovalent metal ions at low temperatures, high selectivity for the metal ions, good current efficiency and stability in water and corrosive media under static and electrochemical conditions. The metal ion conducting ceramic materials are fabricated to be deficient in the metal ion. One general formulation of the metal ion conducting ceramic materials is Me1+x+y?zMIIIyMIV2?ySixP3?xO12?z/2, wherein Me is Na+, Li+, K+, Rb+, Cs+, Ag+, or mixtures thereof, 2.0?x?2.4, 0.0?y?1.0, and 0.05?z?0.9, where MIII is Al3+, Ga3+, Cr3+, Sc3+, Fe3+, In3+, Yb3+, Y3+, or mixtures thereof and MIV is Ti4+, Zr4+, Hf4+, or mixtures thereof.

Abstract: Metal ion conducting ceramic materials are disclosed having characteristics of high ion conductivity for certain alkali and monovalent metal ions at low temperatures, high selectivity for the metal ions, good current efficiency and stability in water and corrosive media under static and electrochemical conditions. The metal ion conducting ceramic materials are fabricated to be deficient in the metal ion. One general formulation of the metal ion conducting ceramic materials is Me1+x+y?zMIIIyMIV2?ySixP3?xO12?z/2, wherein Me is Na+, Li+, K+, Rb+, Cs+, Ag+, or mixtures thereof, 2.0?x?2.4, 0.0?y?1.0, and 0.05?z?0.9, where MIII is Al3+, Ga3+, Cr3+, Sc3+, Fe3+, In3+, Yb3+, Y3+, or mixtures thereof and MIV is Ti4+, Zr4+, Hf4+, or mixtures thereof.

Abstract: A method is provided to recycle and synthesize aqueous alkali chemicals from industrial and radioactively contaminated alkali salt based waste streams using a two-compartment electrolytic cell having an alkali cation-conductive ceramic membrane. The processes and apparatus provide the capability of recycling and synthesizing value added chemicals, including but not limited to, alkali hydroxides.