A method for manufacturing a sulfuric acid solution includes supplying a chloride ion-containing sulfuric acid solution as an initial electrolyte in an electrolyzer inside of which is divided into an anode chamber and a cathode chamber by a diaphragm; and subsequently taking out a metal dissolved electrolyte in which a metal constituting the anode is dissolved from the anode chamber while supplying a current to an anode and a cathode disposed in the electrolyzer.

A method for manufacturing a sulfuric acid solution includes supplying a chloride ion-containing sulfuric acid solution as an initial electrolyte in an electrolyzer inside of which is divided into an anode chamber and a cathode chamber by a diaphragm; and subsequently taking out a metal dissolved electrolyte in which a metal constituting the anode is dissolved from the anode chamber while supplying a current to an anode and a cathode disposed in the electrolyzer.

A catalyst structure is provided. The catalyst structure includes a porous carrier and a plurality of layered hydroxides. The porous carrier includes a nitrogen-doped carbon framework, a plurality of metal oxide particles and a plurality of carbon nanotubes. The nitrogen-doped carbon framework has a plurality of pores. The metal oxide particles are uniformly dispersed in the pores of the nitrogen-doped carbon framework. The carbon nanotubes are located on a surface of the nitrogen-doped carbon framework, and one end of each of the carbon nanotubes is connected to the surface of the nitrogen-doped carbon framework. The layered hydroxides are coated on the surface of the nitrogen-doped carbon framework.

A catalyst structure is provided. The catalyst structure includes a porous carrier and a plurality of layered hydroxides. The porous carrier includes a nitrogen-doped carbon framework, a plurality of metal oxide particles and a plurality of carbon nanotubes. The nitrogen-doped carbon framework has a plurality of pores. The metal oxide particles are uniformly dispersed in the pores of the nitrogen-doped carbon framework. The carbon nanotubes are located on a surface of the nitrogen-doped carbon framework, and one end of each of the carbon nanotubes is connected to the surface of the nitrogen-doped carbon framework. The layered hydroxides are coated on the surface of the nitrogen-doped carbon framework.

Described are methods and systems for producing hydrogen using closed-loop geothermal technology from geothermal, oil and gas or other resources. Various configurations and types of closed-loop systems are described which enable the capture, transfer and use of heat from the resource and from chemical reactions from the processes and methods employed and to also create high down bore pressure, in each case to enhance the technical and commercial efficiency of various hydrogen production methods. As hydrogen is created at high pressures and purities which are necessary for delivery and commercial use of hydrogen, the need for additional compression and purification activities is minimized. Various of the methods and systems described can make hydrogen produced from fossil fuel inputs less carbon intensive and make renewable fuel inputs produce hydrogen entirely without carbon outputs, thereby contributing substantially to the reduction of greenhouse gasses.

Described are methods and systems for producing hydrogen using closed-loop geothermal technology from geothermal, oil and gas or other resources. Various configurations and types of closed-loop systems are described which enable the capture, transfer and use of heat from the resource and from chemical reactions from the processes and methods employed and to also create high down bore pressure, in each case to enhance the technical and commercial efficiency of various hydrogen production methods. As hydrogen is created at high pressures and purities which are necessary for delivery and commercial use of hydrogen, the need for additional compression and purification activities is minimized. Various of the methods and systems described can make hydrogen produced from fossil fuel inputs less carbon intensive and make renewable fuel inputs produce hydrogen entirely without carbon outputs, thereby contributing substantially to the reduction of greenhouse gasses.

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

An apparatus and method are provided for the electrochemical production of hydrogen, oxygen and metal hydroxide wherein the metal is derived from a metal silicate. The process involves the electrolysis of a metal salt solution where hydrogen and a metal hydroxide are produced at the cathode, and oxygen, or chlorine, and an acid are produced at the anode. The acid is reacted with a metal silicate producing a soluble metal salt and water that is used in turn to make solid or dissolved metal hydroxide. The net CO.sub.2 and acid gas emissions of the invention and its products may therefore be significantly reduced or turned negative.

An apparatus and method are provided for the electrochemical production of hydrogen, oxygen and metal hydroxide wherein the metal is derived from a metal silicate. The process involves the electrolysis of a metal salt solution where hydrogen and a metal hydroxide are produced at the cathode, and oxygen, or chlorine, and an acid are produced at the anode. The acid is reacted with a metal silicate producing a soluble metal salt and water that is used in turn to make solid or dissolved metal hydroxide. The net CO.sub.2 and acid gas emissions of the invention and its products may therefore be significantly reduced or turned negative.