Abstract: In this process metal ions such as Ag.sup.+, Pb.sup.2+, Co.sup.2+, Cu.sup. 2+, Fe.sup.3+, etc., are extracted through a porous membrane impregnated with the first extractant containing chelating agents. The membrane contacts with an extraction feed on one side, and with the second extractant on the other side, and the objective metal ions are transferred from the feed to the second extractant. Throughout the extraction process, the pH values of the extraction feed, the impregnated extractant solution, and the second extractant are kept in decreasing order.An apparatus used for the above objective is also provided by this invention.

Abstract: A process for producing a spherical chelating resin is disclosed. In the production, a prepolymer is prepared in the absence or presence of a solvent by subjecting a poly-N-substituted polyamine having at least two residual active hydrogen atoms bonded to nitrogen atoms or a poly-N-substituted polyalkylene imine having at least two residual active hydrogen atoms bonded to nitrogen atoms to a poly-addition reaction with an epoxy compound having at least two epoxy groups. The prepolymer is cured by heating and agitating a suspension of the prepolymer in an aqueous solution of a water-soluble high polymer or a nonionic surfactant in the absence or presence of known curing agents for epoxy resins. The resulting spherical cured resin is subjected to a saponification reaction or to a reaction with a hydrazine or a polyamine, and then a spherical chelating resin is obtained.

Abstract: Molybdenum is selectively extracted from an aqueous solution containing various other metal values, e.g. copper, arsenic, iron, bismuth, antimony, tin, and lead in addition to molybdenum. The molybdenum-bearing solution is adjusted to a pH of about 2.0 or less, and, then, intimately contacted with an organic extracting solution containing an alpha-hydroxy oxime. The loaded organic phase, containing extracted molybdenum values, is separated from the aqueous raffinate, and the molybdenum values contained in the organic phase are stripped therefrom using an aqueous stripping solution containing ammonium hydroxide. The efficiency with which the molybdenum is stripped from the loaded organic solution is poor unless nonylphenol is present in the organic solution as it is being stripped. The nonylphenol can be added to the system anytime prior to the ammonium hydroxide stripping step, e.g.

Abstract: A method and a device for vapor growing crystals. The crystals are grown in an evacuated ampoule from a liquified sample source material, such that the source material is separated from the growing crystal by one or more capillaries or the like which provide the only pathway between the sample source and the growing crystal. There is a temperature gradient between the sample source and the growing crystal such that the growing crystal is at a lower temperature than the sample source.

Abstract: A quantitative hydrometallurgical process for the selective conversion of lead sulfide (galena) to its sulfate form under ambient conditions of temperature and pressure. The process works in the presence of associated zinc - copper - iron sulfides which survive the process in a relatively unaltered condition. It is directly applicable to ores or derived concentrates of complex sulfide systems. The lead sulfate is isolated from the ore or concentrate system by a brine wash with subsequent conversion to lead chloride. A free concentration of cupric ion is maintained during the leaching stages to act as an oxidation catalyst and to inhibit the dissolution of zinc sulfide. The forward reaction in terms of lead sulfation is controlled by a chlorite-type mineral with both anion and cation exchange capacity added to, or maintained in a dilute sulfuric acid leach cycle.

Abstract: Production of 2-phenyl-ethylene phosphonic acid by reacting styrene with phosphorus pentachloride in a molar ratio of about 1 : 2 in liquid phase and hydrolyzing the resulting complex 2-phenyl-ethylene phosphonic acid tetrachloride with water.