摘要:
A method for purifying a gaseous hydride, which comprises bringing a crude gaseous hydride into contact with at least one material from nickel arsenides, nickel phosphides, nickel silicides, nickel selenides, or nickel borides to remove oxygen contained in the crude gaseous hydride.
摘要:
The invention provides a method for accelerating the removal and recovery of selenium from aqueous solutions, such as agricultural irrigation drainage streams or mine waste waters by the bioreduction of Se(VI) to Se(IV) species by using Clostridium soil bacteria together with a rapid exchange reaction which occurs between the aqueous selenium species selenous acid (H.sub.2 SeO.sub.3) and pyrite (FeS.sub.2) to remove all forms of selenium from the aqueous solution. The exchange reaction product FeS.Se may be treated with dilute mineral acid such as sulfurous acid to generate hydrogen selenide (H.sub.2 Se), which is burned in air to yield free selenium. The free selenium recovered is available for use in the electronics, photocopying equipment and other industries. A reusable bacteria-containing soil and pyrite filter apparatus for installation in drainage canals and other conduits is additionally provided to facilitate the removal of aqueous selenium pollutants.
摘要:
A process for the preparation of chalcogenide alloy compositions which comprises providing a chalcogenide alloy; admixing therewith crystalline or amorphous selenium; and subsequently subjecting the resulting mixture to evaporation.
摘要:
A process for the direct synthesis of high surface area amorphous chalcogenides of transition metals of Group IV, V, VI and VII elements, comprising the steps of:(1) forming a mixture of:(a) a halide of a said transition metal having the formula MY.sub.n where Y is chlorine, bromine, flurorine, or iodine, and n is 3, 4, 5 or 6, and(b) a source of chalcogen selected from compounds having the formula (R).sub.3 Si--X--Si(R).sub.3 wherein R is alkyl having from 1-4 carbon atoms and X is sulfur, selenium or tellurium,(2) reacting said mixture at a temperature of -77.degree. C. to +160.degree. C.;(3) separating the transition metal chalcogenide from the reaction mixture; and(4) washing said chalcogenide with an inert solvent to remove unreacted materials and the byproducts of the reaction.The high surface area amorphous chalcogenides prepared according to the covalent exchange process of the invention are advantageously used in primary or secondary batteries, particularly lithium cells. They are of amorphous chemical structure as shown by X-ray, Raman and infrared analysis. Their small crystal size, high surface area, and freedom from oxygen and water contamination, make them high activity, rechargeable cathodes in lithium cells.
摘要:
A method for forming metal chalcogenides is disclosed. An atmosphere of an elemental middle chalcogen is formed and a metal is reacted with the chalcogen in the vapor phase to form a metal chalcogenide powder.
摘要:
In order to obtain substances that are optically transparent in the infrared range, usable in the manufacture of optical fibers or radiation emitters, a metal or metalloid chalcogenide other than an oxide is produced by a double-substitution reaction between a starting chalcogen compound--particularly a hydride such as H.sub.2 S, H.sub.2 Se or H.sub.2 Te--and a salt of the desired metal or metalloid, e.g. a chloride. The starting compound and the reactant salt preferably are vaporized at a temperature below the melting point of the resulting metal chalcogenide which thereupon precipitates in the reaction chamber.
摘要:
Dissolved selenium values are removed from an acidic aqueous copper sulphate solution by treating the solution at a temperature of at least about 140.degree. C. with a stoichiometric excess relative to the dissolved selenium of sulphur dioxide or a sulphite solution to produce a selenium-containing precipitate and dissolved cuprous copper. The temperature of the treated solution is maintained at at least about 140.degree. C. and an oxygen containing gas is passed into the treated solution under a pressure of at least about 350 kPa to oxidize dissolved cuprous copper to dissolved cupric copper.
摘要:
This invention relates to a method of utilizing alkali metal hydrides, such as sodium hydride and lithium hydride, under mild and safe conditions. The method may be used to produce bonds between hydrogen and elements such as carbon, silicon, germanium, tin, phosphorous, arsenic, antimony and tellurium. Many organic compounds, such as chlorides, bromides, ketones, aldehydes and acid chlorides, may also be reduced. The elements from the above list are bonded, before the reduction, to electronegative elements such as fluorine, chlorine, bromine, iodine, oxygen, sulfur, selenium and nitrogen.According to the invention, the alkali metal hydride is catalytically activated by a solution of an alkali borohydride in a suitable ether solvent, so that it rapidly replaces the halogens or other electronegative groups by hydrogen atoms.
摘要:
A low cost chemical spray deposition of metal and mixed metal chalcogenides is accomplished by spray depositing an oxide film from a mixture of a salt of the metal in solution with a water soluble hydrocarbon and water solvent. This oxide film is subjected to a heat treatment in the presence of a chalcogenide gas to induce an ion exchange process transforming the metal oxide or mixed metal oxide into the chalcogenide films of the present invention.The deposition process is used to provide efficient selective absorbing surfaces for a solar thermal energy converter. The process may further be employed to produce a thin film photovoltaic device for converting light energy into electricity.
摘要:
This invention relates to a process for the recovery of metal values from copper refinery anode slimes composed largely of copper, selenium, insolubles, and precious metals, including silver, comprising leaching the slimes with a solution containing from 20 to 200 g/l H.sub.2 SO.sub.4 and from 2 to 25 g/l hexavalent chromium at a temperature not exceeding about 80.degree. C., whereby copper dissolution is maximized and selenium and silver dissolution are minimized, separating the leach solution from the undissolved slimes residue, precipitating selenium from the separated leach solution by treatment with metallic copper, and electrowinning copper from the resulting purified solution.
摘要翻译:本发明涉及从铜,硒,不溶物和贵金属(包括银)组成的铜精炼阳极泥中回收金属值的方法,包括用含有20-200g / l H 2 SO 4的溶液浸出泥浆,以及 在不超过约80℃的温度下从2至25g / l六价铬,由此铜溶解最大化并且硒和银溶解最小化,将浸出溶液与未溶解的泥浆残留物分离,从分离的浸出溶液中沉淀硒 通过用金属铜处理,并从得到的纯化溶液中电解提取铜。