A method for making a porous metal article of manufacture is provided. The method includes subjecting a saturated aqueous electrolytic solution wherein silver or copper is a donor in a container with two electrodes, where dendrite crystals of silver or copper or silver or copper nanowires are formed and collected. The collected dendrite crystals or nanowires are pressed and sintered, thereafter cooled to room temperature at room temperature and finally pressing the cooled geometric shape to form the porous silver metal article of manufacture. The collected dendrites crystals or nanowires also can be pressed in a carbon based mold or, alternatively, a non-carbon based mold and in vacuum, sintered, cooled to room temperature.

An electrowinning cell for extracting metals from an electrolyte solution, the electrowinning cell comprising a housing, a solution inlet, a solution outlet, a plurality of anodes, a plurality of cathodes and a product outlet, wherein at least one anode is substantially impermeable and configured to maintain a gap between a lower edge of the anode and the housing, so that fluid flow of solution is directed below the anode, and wherein at least one cathode is secured at a lower edge to the housing to prevent fluid flow below the lower edge of the cathode.

A method for extracting palladium includes: (1) mixing a palladium-containing material with nitric acid and an alkali metal ion-containing catalyst to obtain a mixed solution, heating the mixed solution, and removing a resulting residue to obtain a palladium-containing leaching liquor; and (2) subjecting the palladium-containing leaching liquor obtained in step (1) to separative extraction to obtain metallic palladium or at least one palladium-containing product, and reusing a residual solution for step (1) in a subsequent extraction. The alkali metal ion-containing catalyst of the present disclosure can leach palladium at a higher rate than that when pure nitric acid of the same concentration is used and does not volatilize, such that the recycling of a mother liquor can be realized. The method involves simple operations, has low production costs, greatly shortens the palladium extraction time, does not lead to secondary pollution, and meets the requirements of environmental protection.

A method for extracting palladium includes: (1) mixing a palladium-containing material with nitric acid and an alkali metal ion-containing catalyst to obtain a mixed solution, heating the mixed solution, and removing a resulting residue to obtain a palladium-containing leaching liquor; and (2) subjecting the palladium-containing leaching liquor obtained in step (1) to separative extraction to obtain metallic palladium or at least one palladium-containing product, and reusing a residual solution for step (1) in a subsequent extraction. The alkali metal ion-containing catalyst of the present disclosure can leach palladium at a higher rate than that when pure nitric acid of the same concentration is used and does not volatilize, such that the recycling of a mother liquor can be realized. The method involves simple operations, has low production costs, greatly shortens the palladium extraction time, does not lead to secondary pollution, and meets the requirements of environmental protection.

A method for collecting silver ions and phosphoric acid in a waste fluid includes collecting silver chloride from the waste fluid, collecting silver chloride including providing a chloride compound to the waste fluid; and collecting phosphoric acid, collecting phosphoric acid including distilling the waste fluid from which the silver chloride has been collected.

A method for collecting silver ions and phosphoric acid in a waste fluid includes collecting silver chloride from the waste fluid, collecting silver chloride including providing a chloride compound to the waste fluid; and collecting phosphoric acid, collecting phosphoric acid including distilling the waste fluid from which the silver chloride has been collected.

The present invention relates to a carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, and more particularly to an environmentally friendly carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, in which valuable metals selectively adsorbed from e-waste wastewater are oxidized using, as an anode, an electrode including carbon nanotubes and a nano adsorption material capable of selectively adsorbing valuable metals and are simultaneously reduced at a cathode, thereby separating and recovering valuable metals.

The present invention relates to a carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, and more particularly to an environmentally friendly carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, in which valuable metals selectively adsorbed from e-waste wastewater are oxidized using, as an anode, an electrode including carbon nanotubes and a nano adsorption material capable of selectively adsorbing valuable metals and are simultaneously reduced at a cathode, thereby separating and recovering valuable metals.

The present application relates to methods for leaching and extraction of precious metals. For example, the present application relates to methods of leaching gold, palladium and/or platinum from a substance comprising gold, palladium and/or platinum (such as a gold-containing ore or a platinum group metal (PGM) concentrate) using an organic solvent that is water-miscible or partially water-miscible.

The present application relates to methods for leaching and extraction of precious metals. For example, the present application relates to methods of leaching gold, palladium and/or platinum from a substance comprising gold, palladium and/or platinum (such as a gold-containing ore or a platinum group metal (PGM) concentrate) using an organic solvent that is water-miscible or partially water-miscible.