Abstract: A contactless electrolytic polishing apparatus for manufacturing a lead frame having a smooth polished surface includes a polishing tank containing polishing solution and divided by partitions into a first cathode-containing vessel, a first solution-discharge vessel, a first anode-containing vessel, a second solution-discharge vessel, a second anode-containing vessel, a third solution-discharge vessel and a second cathode-containing vessel. A direct current is applied with ripples having a frequency of 40 to 120 Hz alternately to the anode and cathode in the electrolytic polishing tank filled with an electrolytic polishing solution so that the time for which the blank positioned between both electrodes functions as the anode may be at least 3.3 times longer than that for which it functions as the cathode. The blank is then plated with a metal by employing a customary method.

Abstract: In a process for treating manganese nodules wherein the nodules are reduced so as to convert most of the nickel, copper and cobalt impurities to their metallic state while inhibiting the conversion of the iron and manganese impurities to their metallic state, the resulting reduced ore is wet ground, if necessary, slurried and treated with an aqueous ammoniacal solution containing free oxygen to extract the metallic nickel, copper and cobalt as their ammine complexes. The iron and manganese are removed from the aqueous ammoniacal solution containing iron and manganese as impurities by leaching the slurry of reduced ore by adding sodium chloride or ammonium chloride thereto and blowing air in the leach solution which also contains sulfur dioxide.

Abstract: A flotation process in which copper ores or copper converter slags are ground and firstly have added thereto benzotriazole or alkyl benzotriazole as an activator and secondly one or more collectors selected from the group consisting of xanthates, dithiophosphates, thiocarbamate esters, dithiocarbamates, mercaptans and dixanthogens and further, if desired, a promoter such as kerosene, light oil, bunker oil or petroleum lubricant is added to improve the recovery for the flotation of copper ores or copper smelter slags.

Abstract: A process for separating and recovering nickel and cobalt is provided wherein a sulfide material containing cobalt and nickel is first oxidation-roasted to remove volatiles and to convert the metallic values into their oxides. These oxides are then dissolved in an aqueous solution of HCl. The solution of chloride salts thus produced is contacted with an extraction solvent comprising an admixture of trinormaloctylamine and xylene whereby the bulk of the cobalt along with the iron, copper and zinc impurities and a portion of the manganese impurities present in the original material are stripped by the extraction solvent while the bulk of the nickel and the remainder of the manganese impurities remain in the aqueous phase. The aqueous phase containing the nickel and manganese impurities is treated with chlorine gas and nickelous carbonate whereby the manganese is precipitated as manganese dioxide. The nickelous chloride solution is then subjected to electrolysis to produce metallic nickel.

Abstract: A process for recovering cobalt as cobalt sulfate solution from cobaltiferous material comprising reducing and smelting oxidized cobaltiferous material rich in iron to extract cobalt as an alloy containing cobalt and iron, which is a neat alloy or an alloy dissolved in a matte, leaving most of the iron in the resultant slag as the first step; converting the cobalt and iron in the alloy into sulfate by treating the alloy, after granulating the pure alloy or pulverizing the mixture of alloy and matte, with copper sulfate and water as the second step; and calcining the resultant mixture containing the sulfates to decompose the iron sulfate selectively into oxide, leaching the resultant calcine to extract cobalt as cobalt sulfate solution, and leaving iron as leach residue as the third step.