Abstract: A process for the recovery of selenium from a urethane solution containing selenium compounds which may be in the form of metallic selenium, inorganic selenium and/or organoselenium compounds which comprises contacting the selenium-containing urethane solution at suitable temperatures with a supported metal or a mixture of metals and/or metal oxide compounds, said metal selectively chosen from Group B metals, i.e., Group IB through VIIIB, metals of the Periodic Table and particularly supported copper and mixtures of copper and other metal oxide compounds of said group.

Abstract: Selenium is removed from copper electrolytes by adding a substance selected from the group consisting of metals above copper in the electromotive series, excluding alkali metals, such as nickel powder, cobalt powder and iron powder. Sodium sulfide can also be used along with a subsequent addition of ferric sulfate. The amount of the reactive substance added should be sufficient to reduce the selenium content to below 2 ppm.

Abstract: Red amorphous selenium is obtained by precipitating selenium from a solution of selenious acid in methanol or ethanol with hydrazine or a soluble salt thereof at a temperature between about -20.degree. C. and the freezing point of the solution. Furthermore, the stable red amorphous selenium may contain a halogen.

Abstract: Red amorphous selenium is obtained by precipitating selenium from a solution of selenious acid in methanol or ethanol with hydrazine or a soluble salt thereof at a temperature between about -20.degree. C. and the freezing point of the solution. Further, the stable red amorphous may contain thallium which may then contain a halogen.

Abstract: Process for preparation of a solid phase dispersion of photoconductive materials in an insulating binder matrix from a film forming insulating polymeric resin and an organo-selenium compound capable of undergoing selective decomposition in response to an appropriate stimulus; whereby, elemental selenium is extruded from said organo-selenium compound and deposited in the binder matrix. Because this extrusion/deposition of elemental selenium can be performed selectively, it is possible to prepare binder films having photoconductive image patterns which are suitable for use in range extended and conventional xerography.

Abstract: There are provided curable anaerobic pressure sensitive adhesive stocks in the form of sheets and tapes in which the adhesive is contained between two differential release surfaces. This construction permits total pressure sensitive adhesive transfer to a substrate which is to be firmly secured to another substrate upon the exclusion of oxygen and initiation of cure of the anaerobic resin.The adhesive layer provided may be homogeneous or heterogeneous, and there may be contained within the adhesive layer a support layer.The release liner employed is preferably impervious to migration of contained compounds which serve as the accelerators for cure of the curable anaerobic resin.

Abstract: A process for recovering pure selenium from metal substrates having a selenium coating thereon without impairment of the substrate for reuse which comprises substantially converting the selenium in said coating to a water-soluble selenocyanate by immersing the coated substrate in an aqueous solution of an alkali metal cyanide, removing the substrate from the resultant solution, treating the resultant solution with an acid to precipitate the selenium from the remaining liquid.

Abstract: The present invention relates to a method and apparatus for purifying selenium or its alloys by precipitation. The method is characterized in that a smaller portion of a larger amount selenium or selenium alloy is kept at the respective transition temperature between solid and liquid phases while the remaining portion is maintained at a higher temperature for a time sufficiently long to allow a substantial concentration of foreign elements in the smaller portion.The apparatus is characterized in that it consists of a glass vessel having a height approximately 10 times its diameter, provided with temperature indicators governing devices controlling the heat supplied to electrical elements arranged around the vessel, it also being provided with a tightly-fitting hood and a gas evacuation device.

Abstract: A thermochemical reaction cycle for the generation of hydrogen from water comprising the following sequence of reactions wherein M represents a metal and Z represents a metalloid selected from the arsenic-antimony-bismuth and selenium-tellurium subgroups of the periodic system:2MO + Z + SO.sub.2 .fwdarw. MZ + MSO.sub.4 (1)mz + h.sub.2 so.sub.4 .fwdarw. mso.sub.4 + h.sub.2 z (2)2mso.sub.4 .fwdarw. 2mo + so.sub.2 + so.sub.3 + 1/20.sub.2 (3)h.sub.2 z .fwdarw. z + h.sub.2 (4)h.sub.2 o + so.sub.3 .fwdarw. h.sub.2 so.sub.4 (5)the net reaction is the decomposition of water into hydrogen and oxygen.

Abstract: Selenium is recovered from combustion waste gas, especially the combustion waste gas evolved from glass melting furnaces by a process in which the waste gas is contacted with an absorbing solution containing an alkali metal sulfite or bisulfite, whereby metallic selenium and selenium compounds are absorbed, the temperature of the waste gas is decreased and the humidity of the waste gas is increased. The treated waste gas in then passed through a moist glass fiber filter which collects the remaining amounts of selenium from the waste gas. The absorbing solution is combined with the solution used to wash the glass fiber filter and the combined solutions are treated with an acid which reduces all of the selenium present in the solution to metallic selenium which precipitates from solution.

Abstract: Red amorphous selenium is obtained by precipitating selenium from a solution of selenious acid in methanol or ethanol with hydrazine or a soluble salt thereof at a temperature between about -20.degree.C. and the freezing point of the solution.

Abstract: Selenium is removed from solution in acidic waste water by treatment of the water with a metallic reducing agent. The invention is particularly effective for removal of selenium from zinc smelter effluent by reaction of the effluent with powdered zinc.