Patent ID: 8173005
Filing Date: 2012-05-08
Classification: C01B,C25C,Y02E,Y02P

Abstract:
1. A process for obtaining hydrogen gas and oxygen gas from water decomposition comprising using a copper-chlorine (Cu—Cl) thermochemical cycle comprising the steps of: 1) reacting electrolytic Cu and dry HCl to obtain hydrogen gas and molten CuCl salt; 2) subjecting solid CuCl and HCl in an aqueous solution to electrolysis to obtain Cu and an aqueous slurry containing HCl and CuCl 3) drying the aqueous slurry obtained from step (2) to obtain solid CuCl 4) reacting the solid CuCl 5) decomposing the solid CuOCuCl wherein at least one first chemical heat pump that upgrades low grade heat from an industrial source to a higher intermediate temperature, supplies heat to the endothermic step 4) of the hydrogen gas production cycle and at least one second chemical heat pump that is a solid-gas heat pump and utilises a high temperature salt to upgrade heat from the exothermic step 1) of the hydrogen gas production cycle, to a higher temperature needed by the endothermic oxygen step 5) of the hydrogen gas production cycle.