An electrochemical process comprises a step E.sup.l of electrolysis of an electrolyte in order to produce gaseous oxygen and a step of converting oxidation-reduction chemical energy into electrical energy with production of H.sub.2. The electrolyte comprises M.sup.m+ ions of a metal M corresponding to the redox pair (M.sup.m+/M), and A.sup.a+ ions of a depolarization additive A corresponding to a redox pair (A.sup.a+/A). Current is supplied between the anode and the cathode, A.sup.a+ and M.sup.m+ are deposited on the cathode respectively in the form of A and M during the electrolysis and gaseous oxygen is released at the anode. The supply of current between the anode and the cathode is then cut off. Depolarization occurs corresponding to the conversion step C°, with production of H.sub.2 and dissolution of M and A into M.sup.m+ and A.sup.a+ at the electrode acting as the cathode during step E.sup.l and the produced H.sub.2 is collected.

A method for extracting metal ions from water is provided that includes disposing two electrically conductive electrodes in water, where the water includes a target ion species in solution, where at least one of the electrically conductive electrodes is a functionalized electrode having species-specific adsorption of the target ion species, and providing electrical current to the electrically conductive electrodes such that the one or more target ion species are deposited to metallic form or metal oxides at the functionalized electrode by one or more electrochemical reactions.

A method for extracting metal ions from water is provided that includes disposing two electrically conductive electrodes in water, where the water includes a target ion species in solution, where at least one of the electrically conductive electrodes is a functionalized electrode having species-specific adsorption of the target ion species, and providing electrical current to the electrically conductive electrodes such that the one or more target ion species are deposited to metallic form or metal oxides at the functionalized electrode by one or more electrochemical reactions.

The method includes two technological segments (i) a reduction segment and (ii) an oxidation segment that are interconnected by various support technological processes for the regeneration of solutions and gases and heat recuperation. The reduction segment includes an electrolysis that is performed from a solution of chloride salts of an energy carrier. During the electrolysis, these elements reduce to a lower oxidation state, solidify on the electrodes or precipitate to a solid state. The solid substance thus obtained is the energy carrier that can be stored outside of the electrolyser until a need for additional energy emerges. During the electrolysis, chlorine gas develops that is collected and dissolved in water. An HCl solution is regenerated, which is used in the oxidation segment. Oxygen is released in this process. The energy that has thus been stored in the oxidation potential of the energy carrier is released during a spontaneous chemical reaction between the energy carrier and the HCl solution in the oxidation segment. In this chemical reaction, the oxidation state of the chemical elements which constitute the energy carrier is increased to an oxidation state identical to that from before the beginning of the electrolysis. The reaction product hydrogen is formed that represents a high calorific fuel. This fuel can be immediately converted to heat or electrical energy, without a need for intermediate storage, by known methods. Only water enters the entire method, oxygen and hydrogen leave, while the cycle is closed/cyclic for the remaining substances.

The present invention concerns a process for the recovery of lead from a lead pastel electrolytically, where the pastel contains lead sulfate. The process provides for the leaching of the non-desulfurised pastel and the subsequent removal of the sulfates by precipitation; the leachate containing the lead ions is then subjected to electrolysis for the recovery of metal lead. The present invention further relates to a process for the recovery of lead accumulator components, wherein the lead contained in the pastel of the accumulators is recovered according to the aforesaid process.

The present invention concerns a process for the recovery of lead from a lead pastel electrolytically, where the pastel contains lead sulfate. The process provides for the leaching of the non-desulfurised pastel and the subsequent removal of the sulfates by precipitation; the leachate containing the lead ions is then subjected to electrolysis for the recovery of metal lead. The present invention further relates to a process for the recovery of lead accumulator components, wherein the lead contained in the pastel of the accumulators is recovered according to the aforesaid process.

A closed loop electrochemical process of recovery of high-purity lead uses continuous formation of adherent lead on a cathode from an electrolyte that is used to dissolve desulfated lead paste. Preferred cathodes include aluminum containing cathodes that are operated in methane sulfonic acid to produce a micro- or nanoporous mixed matrix metallic composition and lead dioxide formation at the anode is avoided using appropriate anode configurations or operating conditions

A closed loop electrochemical process of recovery of high-purity lead uses continuous formation of adherent lead on a cathode from an electrolyte that is used to dissolve desulfated lead paste. Preferred cathodes include aluminum containing cathodes that are operated in methane sulfonic acid to produce a micro- or nanoporous mixed matrix metallic composition and lead dioxide formation at the anode is avoided using appropriate anode configurations or operating conditions

The method includes two technological segments (i) a reduction segment and (ii) an oxidation segment that are interconnected by various support technological processes for the regeneration of solutions and gases and heat recuperation. The reduction segment includes an electrolysis that is performed from a solution of chloride salts of an energy carrier. During the electrolysis, these elements reduce to a lower oxidation state, solidify on the electrodes or precipitate to a solid state. The solid substance thus obtained is the energy carrier that can be stored outside of the electrolyser until a need for additional energy emerges. During the electrolysis, chlorine gas develops that is collected and dissolved in water. An HCl solution is regenerated, which is used in the oxidation segment. Oxygen is released in this process. The energy that has thus been stored in the oxidation potential of the energy carrier is released during a spontaneous chemical reaction between the energy carrier and the HCl solution in the oxidation segment. In this chemical reaction, the oxidation state of the chemical elements which constitute the energy carrier is increased to an oxidation state identical to that from before the beginning of the electrolysis. The reaction product hydrogen is formed that represents a high calorific fuel. This fuel can be immediately converted to heat or electrical energy, without a need for intermediate storage, by known methods. Only water enters the entire method, oxygen and hydrogen leave, while the cycle is closed/cyclic for the remaining substances.

The present application relates to the electrochemical extraction of lead (Pb) from a lead-containing material using a deep eutectic solvent. This is of particular use in the recycling of the lead-based materials that result from energy generation processes.