Abstract: Acidic stripping solutions comprising hydrogen peroxide as oxidant, either at least one phosphorous-oxy acid, or the addition of nitric acid, together with accelerators and surface active agents, are effective for the rapid and selective removal of protective hard surface coatings and nickel-base brazes from a variety of metal surfaces.

Abstract: Gold sand resulting from the nitric acid treatment of silver refinery slimes is purified by washing with hydrochloric acid under controlled operating conditions. Platinum and other precious metals and impurities are selectively separated from the gold sand leaving a gold sand which is more efficiently refined.

Abstract: A composition and process is disclosed for improving the leach resistance of the copper oxide coating on the copper circuitry of printed circuit boards to solutions used in their preparation which comprises contacting the copper oxide of the circuit board with a solution containing an amphoteric element which forms an acidic oxide, such as selenium dioxide.

Abstract: A method for the regeneration of a spent aqueous ammonium bifluoride-hydrogen peroxide solder stripping solution containing contaminant tin ions comprising adding potassium ions to the solution to precipitate a filterable tin-potassium compound.

Abstract: A process is provided for increasing the strength of antimony-lead alloys by specially treating an alloy which contains an effective amount of arsenic in the alloy, the process comprising working the alloy, rapidly heat treating the alloy, which includes quenching, for a period of time sufficient to activiate a strengthening mechanism in the alloy. The process is especially useful for the manufacture of battery grids on a continuous production line.

Abstract: An improved alkaline permanganate composition for etching printed circuit boards is provided by incorporating a secondary oxidant in the solution capable of oxidizing manganate ion to permanganate ion.

Abstract: Acidic stripping solutions comprising hydrogen peroxide as oxidant, either at least one phosphorous-oxy acid, or the addition of nitric acid, together with accelerators and surface active agents, are effective for the rapid and selective removal of protective hard surface coatings and nickel-base brazes from a variety of metal surfaces.

Abstract: A method for the recovery and reuse of an expensive palladium-tin catalyst whereby alkali hydroxide or carbonate is added to the exhausted catalytic solution and/or the spent rinse water solution to precipitate out a catalyst residue, which is then filtered, collected, washed, and dissolved in a hydrohalide acid and adjusted to a predetermined concentration.

Abstract: An improved alkaline permanganate composition for etching printed circuit boards is provided by incorporating a secondary oxidant in the solution capable of oxidizing manganate ion to permanganate ion.

Abstract: A process is provided for improving the electroless nickel plating of aluminum which has been pretreated with a barrier coating such as zinc by employing multiple plating baths under controlled operating conditions.

Abstract: Stripping solutions comprising hydrogen peroxide and sulfamic acid in correlated amounts are effective for the rapid and selective removal of nickel from mild steel surfaces and nickel, nickel alloy and nickel reaction products from alloy substrates. The compositions contain sulfamate, nitrate and chloride and peroxide ions and, preferably, an iron complexing agent such as ethylene diamine tetraacetic acid.

Abstract: High-velocity gas burners having enhanced flame stability over wide operating ranges are provided by correlating the dimensions of the combustion chamber with other burner dimensions, in particular, the ratio of the combustion chamber diameter to the flame holder exit diameter and the ratio of the effective length of the combustion chamber to the combustion chamber diameter.

Abstract: Lead is separated from material containing lead sulfide, e.g., galena ore concentrate, by a substantially autogenous process involving establishing a pool of molten lead in a kettle, adding a metallic alkali metal, e.g., metallic sodium, to the molten lead in an amount sufficient to reduce the combined lead of the lead sulfide to metallic lead, adding the ore concentrate to the molten lead pool, and mixing together the metallic sodium, molten lead and ore concentrate. The sodium reacts rapidly and exothermically with the lead sulfide to reduce the combined lead of the lead sulfide to metallic lead and form sodium sulfide. The thus-liberated metallic lead reports in the molten lead pool, and a matte phase containing the sodium sulfide separates from the molten lead and forms on the surface of the molten lead pool.

Abstract: A process for precise controlling of thiourea concentrations in a copper sulfate, sulfuric acid solution used in copper refining has permitted improvements in tankhouse current efficiencies and the quality of the refined copper deposited on the cathodes.

Abstract: A sintering machine for pulverulent ore concentrates containing sulfidic metals including an ignition zone, a sintering zone and at least two cooling zones wherein there is total recirculation of cooling gases between two cooling zones and including a recuperative heat exchanger for cooling the exhaust gas from the first cooling zone, prior to its introduction to the second cooling zone.

Abstract: The invention relates to an electrode for use in electrometallurgical processes, particularly for use as an anode in copper electrorefining to deposit copper onto starting blanks to make starting sheets or cathode products. The electrode is characterized by having a continuous planar configuration having a top, bottom and two vertical sides with two integral, distinct and separate legs extending from the bottom and adjacent to each of said vertical sides.

Abstract: A process for the production of a vulcanized latex protective coating bonded to the surface of an asbestos-cement article, particularly a pipe, is disclosed. The process includes a step whereby the latex coating is applied before autoclaving to the article, and becomes a hard, protective bonded layer during the autoclaving process.

Abstract: A process for precise controlling of thiourea concentrations in a copper sulfate, sulfuric acid solution used in copper refining has permitted improvements in tankhouse current efficiencies and the quality of the refined copper deposited on the cathodes.

Abstract: A method for the introduction of sodium into lead bullion followed by controlled solidification results in higher recovery of lead from the matte and speiss, and the elimination of the expensive undesirable dross reverberatory practice.

Abstract: A non-phosphate and non-Nta-containing detergent composition comprising from about 30 to 95% by weight of a detergent, especially an anionic or nonionic detergent and from about 5 to 70% by weight of chelidamic acid or 4-hydroxy-2,6-pyridine dicarboxylic acid hereinafter referred to as "4H" acid, and salts thereof.