▎ 摘　　要

NOVELTY - Recovering metal from metal-containing material by leaching, involves providing aqueous solution containing leaching agent precursor; providing one or more source(s) of external energy comprising a source of electric current connected to one or more non-metallic electrode(s) comprising carbon material(s) and/or derivatives selected from graphite, graphene and carbon nanomaterial(s) selected from carbon nanofibers, carbon nanotubes and carbon nanobuds; treating the aqueous solution with the external energy, which is electric current providing electrochemical reactions, to form hydrogen peroxide from oxygen in the aqueous solution, preferably by electrochemical oxygen reduction; reacting the leaching agent precursor with the formed hydrogen peroxide to form a leaching agent and to obtain a leaching solution; providing metal-containing material; reacting the metal-containing material with the leaching solution to obtain soluble metal complexes, and recovering the soluble metal complexes. USE - The method or device is useful for recovering metal from metal-containing material by leaching (claimed). ADVANTAGE - In simple leaching method and device for recovering metals from metal-containing materials, the process can be implemented by providing external non-chemical energy to the process, for example by using electrochemical reactions, such as electrolysis/electrosynthesis, ultrasound, plasma and/or laser. In the method, lesser or no additional chemical agents are required and the process can be controlled and maintained with less additional reagents. The process can be also controlled electronically, which enables fast and accurate control of the reactions, also automation of the control. This results in an efficient and safe method where inexpensive and safe agents can be used. The use of hazardous chemicals, such as cyanide materials or strong acids, for example sulfuric acid or nitrohydrochloric acid, can be avoided. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a device for recovering metal from metal-containing material by leaching, comprising a reactor arranged to receive metal-containing material and aqueous solution, source(s) of external energy arranged to provide external energy to the aqueous solution (14) in the reactor, the source of external energy comprising one or more non-metallic electrode(s) comprising carbon material(s) and/or derivatives selected from graphite, graphene and carbon nanomaterial(s) selected from carbon nanofibers, carbon nanotubes and carbon nanobuds, connected or arranged to be connected to a source of electric current to provide electrochemical reactions, preferably to obtain electrochemical oxygen reduction reaction, to form hydrogen peroxide; a measuring device arranged to measure one or more reaction product(s) obtained to the aqueous solution by using the external energy; a control unit operatively connected to the sources of external energy and to the measuring device, the control unit being, as a feedback to the measurement, arranged to adjust the source(s) of external energy to obtain a desired level of reactions, such as the electrochemical oxygen reduction reactions, in the aqueous solution; and preferably component for recovering metal complexes from the solution.