Abstract: A process and a device serve for decreasing the oxygen content of a copper melt. One or more flushing plugs, from which a scavenging gas emerges, are arranged in the perpendicular direction in the lower region of the copper melt. The scavenging gas ascends into the copper melt, and the copper melt itself is electrically stirred. The copper is initially melted in a shaft furnace, and then it is led to a treatment furnace via a transportation channel. As a result of flowing out of the flushing plugs, the scavenging gas ascends into the copper melt both in the region of the transportation channel and also in the region of the treatment furnace. The scavenging gas flows out of at least one of the flushing plugs with a composition corresponding to 30% to 70% reducing gas and 70% to 30% inert gas.

Abstract: The invention relates to copper-based catalysts, processes for their production and their use and to a process for the production of alkyl halosilanes in the presence of said catalysts.

Abstract: The copper powder contains at least one substance, which is not soluble in copper, e.g. Al.sub.2 O.sub.3, TiO.sub.2, SiO.sub.2 or B.sub.2 O.sub.3. For the production of this copper powder, a surplus of copper metal granulate is mixed with an ammonium salt and/or ammonium hydroxide, together with a saline solution in an aqueous solution, while a gas containing oxygen is added, and at a pH-value of at least 4. A copper-containing precipitate is produced, which is separated and treated at a temperature in the range from 150.degree. to 500.degree. C. in a reducing atmosphere. During this process, Cu(OH).sub.2 and Cu-oxide are transformed into metallic copper powder, which contains the dispersoid. The dispersoid content of the copper powder is preferably in the range from 0.1 to 5% by weight.

Abstract: For their wet purification, gases flowing in a line are sprayed with scrubbing liquor, the resulting mixture of gas and liquid is passed through a cyclone separator. The gas is initially sprayed in a pre-scrubbing line and the gas which contains scrubbing liquor is subsequently conducted through a substantially horizontal accelerating line having at its entrance a cross-sectional area which is 1.5 to 8 times larger than the cross-sectional area at its exit. The exit of the accelerating line communicates with the cyclone separator. Purified gas is withdrawn from the cyclone separator.

Abstract: In a process of producing copper(I) oxide by the action of an aqueous solution of a mineral acid and of oxygen-containing gas on small-lump copper metal with continuous agitation, a temperature from 10.degree. to 40.degree. C., preferably from 15.degree. to 35.degree. C., is maintained to effect a formation of particulate yellow copper(I) oxide (Cu.sub.2 O). An organic acid of the group consisting of formic acid, acetic acid, ascorbic acid, preferably ascorbic acid, may be used in addition to the mineral acid.

Abstract: A process of producing blue copper hydroxide, wherein copper metal is treated with an ammonium ion-containing aqueous solution with stirring and with a simultaneous introduction of an oxygen-containing gas and the reaction product is separated from the copper metal. A particulate, floatable copper (II) hydroxide is produced in that a material which contains copper metal is treated at a temperature of 0.degree. to 40.degree. with a solution which contains 0.1 to 10 g/l ammonium salt (calculated as NH.sub.4), 0 to 10 g/l ammonium hydroxide (calculated NH.sub.3) and, if desired, 0 to 5 g/l copper (II) salt and the resulting copper (II) hydroxide is separated.

Abstract: Metallic or ceramic hollow spheres are produced by applying a solid layer to a substantially spherical particle of foamed polymer and the coated polymer cores are pyrolyzed with formation of vapor. In order to permit an economical production of the hollow spheres and a wide selection from a wide range of metallic or ceramic materials, the particles consisting of foamed polymer are treated in a state of agitation with an aqueous suspension which contains dissolved or suspended binder and metallic and/or ceramic powder particles, whereby a coating is formed on said polymer particles. The coating is dried, the polymer particles and least part of the binder are subsequently pyrolyzed at temperatures from 400.degree. to 500.degree. C. with formation of vapor while they are agitated and the resulting metallic and/or ceramic hollow spheres are sintered at temperatures from 1000.degree. to 1500.degree. C. while they are agitated.

Abstract: A process and apparatus for granulating slag in which molten slag is charged into a drum and is solidified and granulated therein on cooled surfaces. To ensure a rapid cooling at a high thruput rate, the molten slag is applied to the inside surface of a drum, which rotates on a horizontal axis and has a cooled shell, and the solidified film of slag is mechanically detached from the inside surface after about three-quarters of a revolution of the drum and is discharged.

Abstract: An apparatus is described which serves for a pyrometallurgical processing of fine-grained solids suspended in high-oxygen gases, comprising a generally horizontally extending cylindrical vessel and a combustion shaft, which communicates with and vertically opens into the vessel which is provided with a gas outlet opening and with an opening for discharging molten material. An almost complete separation of the molten particles is effected in that the mouth of the combustion shaft tangentially opens into the vessel at the entrance of a spiral-shaped entrance passage, which opens into a discharge slot, which is formed in the shell of the vessel and which in the lower portion of the shell of the substantially cylindrical vessel extends substantially parallel to the longitudinal axis of the vessel.

Abstract: The effectiveness of organic additives acting as inhibitors during the electrolytic deposition of metals from aqueous electrolytes, which contain organic additives for improving the deposition of metal, is electrically measured. In order to permit an improved and more reliable check of the effectiveness of the inhibitor and to permit a controlled supply of makeup inhibitors at the required rate, a partial stream of the electrolyte is supplied to flow at a constant velocity in a measuring cell provided with at least three wire electrodes having a fresh conductor surface, a measuring current of 5 mA to 1.0 A is supplied to the electrodes and is maintained, and the slope of the plotted cathode potential-time curve in the range from 0.1 to 50 minutes is taken as a measure of the effective conecentration of the inhibitor.

Abstract: Nonferrous metal powder or nonferrous metal powder mixtures are made by reacting a metal compound in an aqueous medium with an aqueous sugar or starch solution with stirring and optionally at an elevated temperature and the precipitated metal powder is separated. The nonferrous metal oxide or hydroxide in a concentration between 20 and 400 g/l (calculated as metal) is treated in the aqueous medium at a pH-value above 3.2 and at a temperature between 20.degree. and 160.degree. C. and the virtually oxide free nonferrous metal powder which is precipitated is separated. Oxides or hydroxides of the metals Cu, Ag, Ni, Co, Sn, Pb, Sb, As, or Bi are used.

Abstract: A cathode for use in the electrolytic refining of copper which comprises a carrying bar and a flat starting plate, which is secured to the carrying bar and made of special steel and provided with electrically insulating edge strips at least at its vertical longitudinal edges, which are formed in their edge faces with a groove, which contains an edge strip, that is made of a natural or synthetic polymer and fits into said groove and protrudes from the edge throughout its length. To prevent a deposition of metal in the critical region, the insulating edge strip which has been fitted into the dovetail groove has been formed by a longitudinal folding of a polymer film and contains at its fold line a wire of special steel, and the side portions of said film are coextensive and lie one over the other and are liquid-tightly joined to each other. The invention relates also to a process of manufacturing the cathode.

Abstract: An apparatus for producing ignitable solids-gas suspensions has a feeder for vertically feeding the solids-primary gas suspension, a secondary gas passage concentrically surrounding said feeder, and a stage for mixing both streams.

Abstract: A method for the continuous pyrometallurgical processing of copper-lead matte having a high lead content relative to copper. In order to ensure an economical and ecologically satisfactory processing, the following steps are performed in a continuous sequence: (a) In one processing stage a suitable atmosphere is provided and temperatures above 1250.degree. C. and a high turbulence are maintained in a molten bath, volatile lead components are incorporated in a fine dust and liquid matte having a decreased lead content and metallic lead included in a copper-containing lead alloy are produced; (b) in another processing stage, gases which contain free oxygen are blown into or onto the liquid matte which has been produced in stage (a) and is at a temperature above 1250.degree. C.

Abstract: A cladding process and apparatus in which steel strip or sheet is cladded with a metal of lower melting point, e.g. lead, by maintaining a bank of constant level of the molten cladding material between a belt and the strip or sheet substrate which passes along an inclined path and is cooled to harden the molten material thereon. During the cooling process the applied material is compressed against the substrate.