Abstract: A zinc production method further includes chlorine-concentration adjusting processes 101, 101?, and 105 of using an alkali hydroxide aqueous solution as an extraction solvent for selectively extracting zinc components in a zinc-containing aqueous-solution generating process 102, and separating chlorine components contained in electric arc furnace dust or secondary dust to decrease the chlorine concentration of a zinc-containing aqueous solution at a stage prior to an electrolyzing process 103.

Abstract: In order to remove fluorine from a zinc containing solution before zinc electro-refining in lower cost, fluorine is removed by adsorption from a zinc containing solution (leached solution) utilizing the character of the predetermined iron compound or zinc compound which can adsorb fluorine in an acid solution and desorb fluorine in an alkaline solution. The fluorine adsorbent/desorbent having adsorbed fluorine is treated in an alkaline solution, to desorb the fluorine. This makes it possible to regenerate the fluorine adsorbent/desorbent. Further, an electrolytic solution for zinc electro-refining can be prepared in lower cost, thus total zinc refining costs can be reduced.

Abstract: In order to remove fluorine from a zinc containing solution before zinc electro-refining in lower cost, fluorine is removed by adsorption from a zinc containing solution (leached solution) utilizing the character of the predetermined iron compound or zinc compound which can adsorb fluorine in an acid solution and desorb fluorine in an alkaline solution. The fluorine adsorbent/desorbent having adsorbed fluorine is treated in an alkaline solution, to desorb the fluorine. This makes it possible to regenerate the fluorine adsorbent/desorbent. Further, an electrolytic solution for zinc electro-refining can be prepared in lower cost, thus total zinc refining costs can be reduced.

Abstract: In order to remove fluorine from a zinc containing solution before zinc electro-refining in lower cost, fluorine is removed by adsorption from a zinc containing solution (leached solution) utilizing the character of the predetermined iron compound or zinc compound which can adsorb fluorine in an acid solution and desorb fluorine in an alkaline solution. The fluorine adsorbent/desorbent having adsorbed fluorine is treated in an alkaline solution, to desorb the fluorine. This makes it possible to regenerate the fluorine adsorbent/desorbent. Further, an electrolytic solution for zinc electro-refining can be prepared in lower cost, thus total zinc refining costs can be reduced.

Abstract: In a metal-winning method, copper ore or copper-ore concentrates is effectively hydraulically leached in a chloride leach liquor and the resultant leached liquor is diaphragm-electrolyzed. A chloride electrolyte containing Br? ions and the leached metals is subjected to a diaphragm-electrolysis in an electrolytic cell comprising an anode compartment (4) and a cathode compartment (3). A portion of the electrolyte in the anode compartment (4) is withdrawn from below an anode (2) of the anode compartment (4) and is returned to the leaching step so as to increase the oxidation potential of the chloride leach liquor.

Abstract: A method of producing high purity electrolytic copper through halide-bath electrowinning is provided. The method includes the steps of: growing copper in dendritic form to be deposited on a cathode; and recovering growth ends of 3.0 mm or shorter from the dendrites.

Abstract: In order to remove fluorine from a zinc containing solution before zinc electro-refining in lower cost, fluorine is removed by adsorption from a zinc containing solution (leached solution) utilizing the character of the predetermined iron compound or zinc compound which can adsorb fluorine in an acid solution and desorb fluorine in an alkaline solution. The fluorine adsorbent/desorbent having adsorbed fluorine is treated in an alkaline solution, to desorb the fluorine. This makes it possible to regenerate the fluorine adsorbent/desorbent. Further, an electrolytic solution for zinc electro-refining can be prepared in lower cost, thus total zinc refining costs can be reduced.

Abstract: A method of producing high purity electrolytic copper through halide-bath electrowinning is provided. The method includes the steps of: growing copper in dendritic form to be deposited on a cathode; and recovering growth ends of 3.0 mm or shorter from the dendrites.

Abstract: In a metal-winning method, copper ore or copper-ore concentrates is effectively hydraulically leached in a chloride leach liquor and the resultant leached liquor is diaphragm-electrolyzed. A chloride electrolyte containing Br? ions and the leached metals is subjected to a diaphragm-electrolysis in an electrolytic cell comprising an anode compartment (4) and a cathode compartment (3). A portion of the electrolyte in the anode compartment (4) is withdrawn from below an anode (2) of the anode compartment (4) and is returned to the leaching step so as to increase the oxidation potential of the chloride leach liquor.