Abstract: Zinc and lead are usually concomitantly present in Zn—Pb ores and tailings. A novel non-polluting hydrometallurgical process for selectively leaching and recovering zinc (Zn) from a composite lead (Pb) and zinc sulphide containing mineral, crushed untreated rock or unconsolidated mineral particles, mill tailings and/or agglomerated or unagglomerated sulphidic zinc containing waste material without necessitating smelting and refining operation has been developed. A combination of selected oxidant and alkali metal hydroxide has been found effective. A leachant consisting of e.g. a mixture of sodium hydroxide (NaOH) and sodium hypochlorite (NaOCl) is employed to selectively dissolve zinc sulphide at high pH at standard temperature and pressure (STP). The kinetics of leaching along with the effect of varying concentration (preferably of sodium hydroxide and sodium hypochlorite) were systematically investigated. Feed ore containing diverse set of minerals e.g.

Abstract: A polymer, a composition, and uses for either are disclosed. The polymer is derived from at least two monomers: acrylic-x and an alkylamine, and has attached to the polymer backbone a functional group capable of scavenging at least one metal. The polymer has a polymer backbone with a fluorescing quantity of conjugated double bonds, thereby providing a method for controlling metal scavenging via fluorescence. These polymers have many uses in various media, including wastewater systems.

Abstract: Zinc oxide particles having high transparency in visible light and high shielding properties in a ultraviolet region, with surface treatment of inactivating photocatalytic activity applied thereto, and a dispersion thereof. A manufacturing method of surface treated zinc oxide particles, including: a first step of mixing a dispersion liquid with zinc oxide particles dispersed in a solvent, and silicone resin having polysiloxane bond with at least one or more silicon atoms having a silanol group (Si—OH) and/or alkoxy silyl group (Si—OR, wherein R is alkyl group); obtaining a mixed solution containing a surface treated zinc oxide particles precursor, with the silicone resin adsorbed on the surface of each zinc oxide particle and the solvent, and drying and solidifying the mixed solution by applying heat treatment thereto, to thereby manufacture a dried body; and a second step of pulverizing the dried body, to thereby manufacture the surface treated zinc oxide particles.

Abstract: Non-spherical siliceous particles having a plurality of porous branches are disclosed and claimed. The porous branches are randomly oriented and elongated, ring-like, and/or aggregated. An additive introduced during synthesis of the particles modifies pore volume and morphology. The tunability of the pore volume includes an inner diameter ranging from about 2 ? to about 50,000 ?. Synthesizing the particles includes mixing under constant or intermittent stirring in a reaction vessel an aqueous silicic acid solution with an acidic heel solution to form a mixture. The stirring may optionally be performed at a variable speed. An additive is introduced into the mixture at a controlled rate, wherein the additive imposes a pH change from a lower pH to a higher pH to the mixture to induce siliceous particle precipitation.

Abstract: A method and composition for the reduction of the emission of selenium into the environment from the burning of fossil fuels with the use of two chemistries, either individually or in combination with each other. The method uses polydithiocarbamic compounds, including polydithiocarbamic compounds derived from a polymer produced from acrylic-x and alkylamine in conjunction with a scrubber process to capture selenium and reduce its emission in aqueous phase blowdown. The method and composition also helps reduce corrosion in the scrubber process.

Abstract: A composition comprising a polymer derived from at least two monomers: acrylic-x and an alkylamine, wherein said polymer is modified to contain a functional group capable of scavenging one or more compositions containing one or more metals is disclosed. These polymers have many uses in various mediums, including wastewater systems.

Abstract: A method and composition for the reduction of the emission of selenium into the environment from the burning of fossil fuels with the use of two chemistries, either individually or in combination with each other. The method uses polydithiocarbamic compounds, including polydithiocarbamic compounds derived from a polymer produced from acrylic-x and alkylamine in conjunction with a scrubber process to capture selenium and reduce its emission in aqueous phase blowdown. The method and composition also helps reduce corrosion in the scrubber process.

Abstract: The present invention relates to aqueous processes to make metal chalcogenide nanoparticles that are useful precursors to copper zinc tin sulfide/selenide and copper tin sulfide/selenide. In addition, this invention provides processes for preparing crystalline particles from the metal chalcogenide nanoparticles, as well as processes for preparing inks from both the metal chalcogenide nanoparticles and the crystalline particles.

Abstract: A simple, room-temperature method of producing zinc oxide nanoparticles was established by reacting zinc nitrate hexahydrate and cyclohexylamine (CHA) in either aqueous or EtOHic medium. Particles of polyhedra morphology were obtained for zinc oxide, prepared in EtOH (ZnOE), while an irregular spherical morphology, mixed with some chunky particles forzinc oxide prepared in water (ZnOW). The results indicate that there are significant morphological differences between ZnOE and ZnOW. ZnOE showed a regular polyhedral shape, while spherical and chunky particles were observed for ZnOW. The morphology was crucial in enhancing the cyanide ion photocatalytic degradation efficiency of ZnOE by a factor of 1.5 in comparison to the efficiency of ZnOW at equivalent loading of 0.02 ZnO nanoparticles wt %. Increasing the loading wt % of ZnOE from 0.01 to 0.07 led to an increase in the photocatalytic degradation efficiency from 67% to 90% after 45 minutes and a doubling of the first-order rate constant (k).

Abstract: Uses for a composition comprising a polymer derived from at least two monomers: acrylic-x and an alkylamine, wherein said polymer is modified to contain a functional group capable of scavenging one or more compositions containing one or more metals are disclosed. These polymers have many uses in various mediums, including wastewater systems.

Abstract: Cd-112 isotope is recycled from a Cd-112 chemical separated solution or a remainder of an electroplating solution having a Cd-112 target. The present invention recycles Cd-112 isotope with a low cost, a high purity and a high recycle rate. The recycled Cd-112 isotope can be easily stored. And, the Cd-112 isotope can be used as an imaging agent in nuclear medicine.

Abstract: Disclosed is a method of manufacturing a metal oxide nano powder comprising preparing a first dispersed solution by adding a nano-sized metal powder to water and dispersing the metal powder within the water, performing a hydration reaction of the first dispersed solution at a temperature of about 30 to about 70° C. to generate a precipitation, and filtering and drying the precipitation to prepare a metal oxide powder. Also, disclosed is a metal oxide nano powder manufactured by the method described above, and having any one of a bar-form, a cube-form, and a fiber-form.

Abstract: The separation method for zinc sulfide, in the hydrometallurgical process by a High Pressure Acid Leach for nickel oxide ore comprising leaching and solid/liquid separation step, neutralization step, zinc removal step, and nickel recovery step, which can inhibit clogging of a filter cloth and reduce a frequency of washing operation and replacement operation of a filter cloth by improving filtration performance of zinc sulfide, and inhibit decrease of nickel recovery ratio, in the zinc removal step in which zinc sulfide is formed by adding a sulfurizing agent to the neutralization final liquid containing zinc as well as nickel and cobalt and zinc sulfide is separated to obtain a mother liquid for nickel recovery containing nickel and cobalt. The separation method for zinc sulfide of the present invention is characterized in that in the above-described neutralization step, the leach residue is added to the leach liquor, and pH of the neutralization final liquid is adjusted so as to fall to the range from 3.

Abstract: Method for producing hydrometallurgical zinc oxide powder having characteristics equivalent to that derived from a French process, comprising formation of an aqueous pulp from a starting zinc oxide having particles of nodular structure, wet milling of this aqueous pulp, separation in this milled pulp between a liquid phase and a solid phase containing the zinc oxide, and drying of said solid phase, coupled with a mechanical deagglomeration of the particles during drying, to obtain a dry zinc oxide powder with particles of nodular structure having a particle size distribution where the particles have an average size (d50) between 0.02 and 20 ?m.

Abstract: A method for extraction of zinc values from an aqueous alkaline solution of zinc, especially a solution obtained by the stripping of a galvanized coating from a ferrous metal product e.g. steel, or from electric arc furnace dust. The method comprises subjecting the aqueous alkaline solution to solvent extraction using an organic solution of an oxine i.e. an organic extractant containing an 8-hydroxyquinoline group, and separating the organic solution from aqueous alkaline solution. Zinc values are recovered from the organic solution e.g. by stripping with acid and subjecting the resultant aqueous solution containing zinc values for recovery of zinc e.g. to electrowinning or to precipitation of zinc carbonate. The method may be used in the preparation of galvanized steel for recycle to a steel manufacturing plant, with recovery of zinc and for recovery of zinc values from electric arc furnace dust.

Abstract: The present invention relates to an apparatus and a process for producing zinc oxide from an acid soluble zinc-bearing material. The process according to the present invention comprises the steps of leaching the zinc oxide material with sulphuric acid; precipitating iron and silica from the leach solution using calcium oxide; removing copper, cadmium and cobalt from the leach solution by cementation with zinc dust; precipitating zinc oxide from the leach solution using calcium oxide; and upgrading zinc content in zinc oxide precipitates by separating zinc oxide from gypsum using a flotation or granulometric sizing technique.

Abstract: A method for the preparation of nano size zinc oxide particles having an average primary particle diameter of less than or equal to 15 nm, which are redispersible in organic solvents and/or water, by basic hydrolysis of at least one zinc compound in alcohol or an alcohol/water mixture. The hydrolysis is carried out with substoichiometric amounts of base, based on the zinc compound. The precipitate which originally forms during hydrolysis is left to mature until the zinc oxide has completely flocculated. This precipitate is then thickened to give a gel and separated off from the supernatant phase.

Abstract: A method for preparing a CdS photocatalyst represented by general formula (I): m(a)/Cd[M(b)]S, comprising the steps of: dissolving Cd-containing and M-containing compounds in water in such an amount that the mol % of M ranges from 0.001 to. 20.00; adding one H2S or Na2S as a reactant in the solution with stirring to precipitate Cd[M]S; washing the precipitate with water and vacuum-drying the precipitate in a nitrogen environment at a temperature of 105˜150° C. for 1.5˜3.0 hours; doping a liquid m-containing compound to this precipitate in such an amount that the % by weight of m ranges from 0.10 to 5.00. In the formula, m represents a doped metal element as an electron acceptor selected from the group of Ni, Pd, Pt, Fe, Ru, Co or an oxidized compound of these metals; a represents a percentage by weight of m, ranging from 0.10 to 5.00; M is a promoter selected from the group consisting of V, Cr, Al, P, As, Sb and Pb; b represents mol % of M/(M+Cd), ranging from 0.

Abstract: A sol having dispersed in a liquid medium particles of a hydrated zinc stannate having a primary particle diameter of from 2 to 200 nm and represented by the formula xZnO.ySnO.sub.2.zH.sub.2 O wherein the molar ratio of x:y:z is 1:0.83 to 1.43:1.00 to 5.00.

Abstract: A process for recycling a zinc phosphating system sludge comprising forming a mixture of the sludge with water and phosphoric acid. The mixture is formed at an elevated temperature and a pH of between 1.5 and 2.4. The sludge substantially dissolves in the mixture and iron phosphate precipitates out. The resultant liquid comprises a substantially zinc ion and phosphate ion solution suitable for use as a make-up feed in zinc phosphating system.

Abstract: A process for separately removing zinc and iron from acidic wastewater. The process involves adding alkali metal hydroxide to the acidic wastewater (below about pH 4) to achieve a first pH of about 4.8 to at most about 5.4 and precipitate an iron hydroxide-containing precipitate at this pH. The precipitate from the wastewater is separated and then additional alkali metal hydroxide is added to achieve a second pH in the range from about 8.8 to about 9.4. A zinc hydroxide containing precipitate forms at this second pH and is then recovered by filtration.

Abstract: Flaky fine particles of zinc oxide have an average particle diameter of 0.1 to 1 micron, an average particle thickness of 0.01 to 0.2 micron and a mean platy ratio (aspect ratio) of at least 3. They are useful as an ingredient for an external composition containing a medicine or cosmetic.

Abstract: A method of treating solid hazardous wastes containing unacceptable levels of leachable metals such as lead, cadmium and zinc includes mixing the solid waste with a buffering agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and with an additional agent which is an acid or salt containing an anion that forms substantially nonleachable forms of the metals, which additional agent is selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid and metallic iron so that under both acidic and nonacidic leaching conditions the metals in the mixture will be converted to substantially nonleachable forms.

Abstract: Alkali metal chlorites are produced by the reaction of chlorine dioxide with an alkali metal amalgam in a reaction mixture where the pH is maintained at from about 9.5 to about 11.5 by providing an excess of the alkali metal to the chlorine dioxide of at least 10 mole percent.Alkali metal chlorites obtained by this process are free of insoluble mercury and have reduced concentrations of soluble mercury as a contaminant.

Abstract: An improved technique for purifying a solution of metallic salts from copper and cadmium contained in such solution is described. A bed of zinc granules is disposed on a grid at the bottom of a vertically arranged, cylindrical reaction chamber. The solution to be purified is pumped upwardly through the grid and the zinc bed at a speed in the range of 0.08-0.5 m/sec. to impart a turbulent motion to the zinc granules throughout the height of the reaction chamber. The turbulence causes the copper-cadmium cake adhering to the zinc particles during the reaction to separate from the granules, so that the separated cake flows out of the reaction chamber with the purified liquid to be quickly and easily removed therefrom.

Abstract: Method for recovering potassium hydroxide and zinc oxide from potassium zincate solutions, characterized in that a selective solvent of potassium hydroxide, which is miscible with water, is added to the zincate solution, in that the zinc oxide precipitate thus obtained is filtered and in that the mother liquors for separating the potassium hydroxide solution from the solvent are treated. The invention applies to all electrochemical storage cell batteries having a zinc negative electrode in which it is required to purify the electrolyte with a view to scavenging it.

Abstract: Disclosed is an improved method for the preparation of CdSSe by the reaction in an aqueous medium of CdCO.sub.3 with a soluble metal sulfide and selenium to form a raw cake which is subsequently calcined to form the desired product. During calcination, an inert gas is allowed to flow over the raw cake thereby forming a CdSSe pigment with improved electrical properties for use in electrostatographic copying.

Abstract: Mercury is removed from sulfuric acid by adding finely divided aluminum to the acid, cooling the mixture to a temperature not exceeding about 15.degree.C. and filtering the mixture in from about 1 to about 6 hours.