Abstract: Process for the production of lead hydrate or monoxide of high purity, from materials and/or residues containing lead in the form of sulphates, monoxides and/or other compounds, such as the paste coming from exhaust acid batteries, comprising the following steps of desulphurisation of the material and/or residue containing lead sulphate in an aqueous suspension with a suitable carbonate or hydrate in order to get conversion of the lead sulphate into a carbonate or hydrate, calcination of this desulphurised material and/or residue in order to get impure lead monoxide, followed by cooling and grinding, leaching of the impure lead monoxide by an aqueous solution of acetic acid followed by filtering to separate a solid residue, consisting mainly of non converted lead sulphate, from a lead acetate solution, precipitation of the lead acetate in solution by means of an alkaline hydroxide or alkaline-earth hydroxide, able to obtain soluble acetates, in order to get a precipitate, depending on the precipitation temper

Abstract: A process for producing composite materials with a metal matrix and with a content of powder reinforcer agent lower than is minimum theoretical compaction value, with said process being based on an infiltration technique, is disclosed, which essentially consists in charging the reinforcer material to a casting mould, and then infiltrating into the same mould the metal matrix in the molten state, with said metal matrix being let cool until it solidifies, and characterized in that the reinforcer agent, consisting of non-metal powders, is blended, before being charged to said casting mould, with a diluting agent having a different compaction degree, constituted by metal fibres and/or ceramic fibres and/or ceramic whiskers and/or metal powders of the same composition as of the matrix.

Abstract: There is disclosed a method for the separation of antimony from acidic solutions which contain antimony, alone, or together with other metallic ions, by extracting antimony with an organic, water-immiscible, polyol-containing diluent. The method comprises the steps of contacting the antimony-containing acidic solution with a water-immiscible organic diluent containing at least one polyol dissolved therein, preferably a diol, said polyol serving to extract the antimony. The polyol serves to selectively extract the antimony from the acidic solution to the exclusion of other metallic ions such as copper and nickel.

Abstract: Disclosed is a process for obtaining a metallurgical bond between a metal material, or a composite material having a metal matrix, and a metal casting, or a metal alloy casting, which comprises carrying out a surface treatment on said material by means of the deposition of a thin layer of a metal, generally different from the metals contained in the material and in the casting, which is capable of increasing the wettability between the metal of the casting and the material, as well as the heat transfer coefficient between said two partners; and a step of casting around the same material, positioned inside a mold, of the metal, or of the metal alloy the same casting is constituted by.

Abstract: A composite material is disclosed, which contains a matrix of Zn-Al alloy reinforced with silicon carbide powder, which powder has a granulometric distribution comprised within the range of from 1 to 200 .mu.m.

Abstract: The invention relates to the separation of indium from acidic solutions containing it, by means of the formation of complex compounds with complexing substances supported on either planar or tubular membranes, of ploymeric character, and of the de-complexing of the same, followed by a re-extraction or stripping with acidic solutions, which may be either of the same type of, or different from the starting solutions.

Abstract: A process for separating arsenic from acid aqueous solutions containing arsenic and other metal ions. The process involves bringing the acid aqueous solution into contact with a water-immiscible organic diluent consisting of hydrocarbons, alcohols or their mixtures, in which there is dissolved as solvent at least one polyol. The solvent thereby extracts the arsenic, which is then re-extracted with a counter-solvent.

Abstract: A process for the selective extraction of arsenic from acid solutions containing other metals comprising treating the solutions with polyhydroxybenzene derivatives in organic diluent; mono- and di- alkyl derivatives containing at least four alkyl carbon atoms of pyrocatechol and pyrogallic acid are particularly contemplated for use in the removal of arsenic from strongly acid copper-containing electrolyte solutions.

Abstract: The present invention relates to a composite material comprising a porous lead alloy containing from 0.7 to 1.0% silver or 0.1 to 1.0% calcium or 0.7 to 1.0% silver and 0.1 to 1.0% calcium and having its pores filled by a resin such as epoxy resin. The product has utility as a battery electrode and as a sound absorbing material.

Abstract: Process for the separation of arsenic from acid aqueous solutions containing arsenic and other metals characterized in that the acid aqueous solution is placed in the contact with water-immiscible organic solvent which extracts the arsenic, the arsenic being reextracted from the organic solvent by means of a countersolvent.

Abstract: A corrosion-resisting anode made of a planar sheet of alloyed lead, to be used in industrial cells wherein acidic solutions are circulated, for the electrowinning of non-ferrous metals, such as zinc and cadmium, is characterized in that it is composed by 98.9 to 99.9% of lead, from 0.1 to 1% calcium and from 0 to 0.1% silver.

Abstract: To solve pollution problems in electrolytic cells for the production of zinc by electrolyzing a solution of a zinc salt, shielding baffles are provided above the cell anodes, the gap between adjoining baffles being such as to provide a satisfactory tight seal while permitting the evacuation of noxious gases and mists through manifolds formed through the cell walls.