초록 ▼

The present invention relates to an electrochemical cell and a process for producing a hydroxide solution, sulfuric acid and a halogen gas from a hydrogen halide and a sulfate solution. In particular, the sulfate solution may be an alkali metal sulfate solution, such as sodium or potassium sulfate s

The present invention relates to an electrochemical cell and a process for producing a hydroxide solution, sulfuric acid and a halogen gas from a hydrogen halide and a sulfate solution. In particular, the sulfate solution may be an alkali metal sulfate solution, such as sodium or potassium sulfate solution, an alkaline earth metal sulfate solution or an ammonium sulfate solution. The cell and the process may use either an anhydrous or an aqueous hydrogen halide, namely, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a respective dry halogen gas, such as chlorine, fluorine, bromine, or iodine, to produce hydrogen ions in order to split the alkali metal solution and form the sulfuric acid. The cell has two membrane-electrode assemblies, where an anode is disposed in contact with one membrane, and a cathode is disposed in contact with another membrane. The sulfate solution is fed in between the membrane-electrode assemblies.

대표청구항 ▼

[ What is claimed is:] [13.] A process for producing a sodium hydroxide solution, sulfuric acid and chlorine from essentially anhydrous hydrogen chloride and a sodium sulfate solution, wherein:(a) a sodium sulfate solution is fed to a first compartment of an electrochemical cell, wherein the sodium

[ What is claimed is:] [13.] A process for producing a sodium hydroxide solution, sulfuric acid and chlorine from essentially anhydrous hydrogen chloride and a sodium sulfate solution, wherein:(a) a sodium sulfate solution is fed to a first compartment of an electrochemical cell, wherein the sodium sulfate solution comprises sulfate ions and sodium ions;(b) molecules of essentially anhydrous hydrogen chloride are fed to a second compartment of the electrochemical cell and are transported to an anode of the cell;(c) the molecules of anhydrous hydrogen chloride are oxidized at the anode to produce halogen gas and protons, and the protons are transported through a first cation-transporting membrane;(d) the first membrane rejects the sulfate ions and the sulfate ions join the protons to form a sulfuric acid solution;(e) water is fed to a third compartment of the electrochemical cell and is reduced to hydrogen and hydroxyl ions; and(f) a second membrane rejects the hydroxyl ions and the hydroxyl ions are joined with the sodium ions to form a solution of hydroxide.