Abstract: The invention relates to a method for the treatment of fluoboric electrolyte resulting from the processes of electro-extraction of metals such as copper and lead comprising a leaching stage with fluoboric acid, in order to recycle said fluoboric acid to be recirculated to said leaching stage devoid of impurities of metals such as Me=Fe, Zn, Ca, Mg, Cd, characterized in that it comprises the stages of: a) treating said fluoboric electrolyte comprising Cu(BF4)2 or Pb(BF4)2 with H2S in order to precipitate CuS or PbS respectively in accordance with the reactions Cu(BF4)2+H2S=>CuS+2HBF4  (1) Pb(BF4)2+H2S=>PbS+2HBF4  (2) thus obtaining a solution of HBF4 containing the fluoborates of said metals Me, said solution being separated, b) treating said Me fluoborates with H2SO4 in accordance with the reaction 2 Me(BF4)n+n H2SO4=>Me(SO4)n+2n HBF4  (3) (where Me=Fe, Zn, Ca, Mg, Cd) it being possible for said sulp

Abstract: This process treats copper concentrates, either in the form of a primary sulfide, such as chalcopyrite, or a secondary sulfide, such as chalcocite and covellite, to obtain high purity copper metal having not less than 99.99% purity. In the case of a primary sulfide, the copper concentrate is subjected to leaching and is transformed into cement or a precipitated sulfide. In the case of the secondary sulfide, the copper concentrates are subjected to leaching with ferric fluoborate and fluoboric acid. Subsequent to leaching, the solution is subjected to copper electrowinning in a diaphragm cell to deposit copper on the cathode of the diaphragm cell.

Abstract: A process for processing electric steelworks dusts containing oxidized high-iron, zinc-bearing materials in order to recover iron and zinc from [them] said dusts. The process includes the steps of: feeding the dusts to an induction furnace partially filled with a charge of metal or alloy to be smelted, wherein the charge is present as a molten bath that is made turbulent by induced currents; contacting the dusts with a surface of the turbulent molten bath inside the furnace; and reducing zinc and iron oxides contained in the dusts inside the furnace, while oxidizing zinc and carbon monoxide rising from the bath.

Abstract: The copper is selectively precipitated in the form of a sulfide from the solutions containing it, according to the reaction:Cu.sup.2+ +S.sup.2- .fwdarw.CuSThe precipitated solid, constituted by copper sulfide, is filtered, washed and then leached with a solution of ferric fluoborate and fluoboric acid, which dissolves the copper as a fluoborate while forming elemental sulfur, according to the reaction:CuS+2Fe(BF.sub.4).sub.3 .fwdarw.Cu(BF.sub.4).sub.2+2Fe(BF.sub.4).sub.2 +S.sup.oAfter filtering off the sulfur, the copper fluoborate solution is subjected to an electrolysis in a diaphragm cell, obtaining a deposit of pure copper at the cathode and a regenerated solution of ferric fluoborate at the anode, which is utilized to leach further copper sulfide.

Abstract: The conditions for electrowinning Zn, Ni, Co and Cd metals from baths based on chlorinated ammino complexes of Me(NH.sub.3).sub.n Cl.sub.m type are substantially improved by the addition of small levels of dissolved Br, which considerably reduce the cell voltage without exerting any negative effects on cathodic current yields.

Abstract: A process for producing metals, Me, selected from zinc, nickel, cadmium and cobalt, in which the corresponding water-soluble ammino complex Me(NH.sub.3).sub.n Cl.sub.m is formed, and such a complex, in an aqueous solution, is submitted to electrolysis in a cell which is free of there being a separator structure between the anodic and the cathodic compartments.

Abstract: A process for the production of alkali metal hydroxides, such as caustic soda, and elemental sulfur, characterized in that to an electrochemical cell an aqueous solution of an alkali metal sulfide, e.g., sodium sulfide, is fed in order to cause the following reactions to take place:at the anode Na.sub.2 S.fwdarw.2Na.sup.+ +S+2e.sup.-at the cathode 2H.sub.2 O+2e.sup.- .fwdarw.2OH.sup.- +H.sub.2with the overall reaction being thus the following:Na.sub.2 S+2H.sub.2 O.fwdarw.2NaOH+S+H.sub.2.Elemental sulfur, which is insoluble, is recovered from the anodic solution by filtration. The NaOH solution is extracted from the cathodic compartment by the addition of water. The concentration of the solution of alkali metal hydroxide obtained is a function of the characteristics of the membrane used. The standard potential of the anodic reaction:S.sup.2- -2e=S.sup.0is lower than of the corresponding processes which led to the development of gases (Cl.sub.2, O.sub.

Abstract: Copper scrap, reduced to particulate form having particle sizes not larger than 50 mm, is leached in a suitable apparatus with a solution of ferric fluoroborate in fluoroboric acid. During leaching, copper is dissolved, with ferric fluoroborate simultaneously being reduced to ferrous fluoroborate according to the following reaction:2 Fe(BF.sub.4).sub.3 +Cu.fwdarw.Cu(BF.sub.4).sub.2 +2 Fe(BF.sub.4).sub.2(1)The resulting solution is fed to the cathodic compartment of diaphragm cell, in which copper is deposited, in compact and highly pure form, on a stainless steel cathode, from which it is periodically recovered.