Abstract: A method of removing mercury vapor from a gas contaminated therewith comprising washing said gas with an acid solution of divalent mercury ions, the concentration of which ranges from 0.5 to 100g per liter, at room temperature and atmospheric pressure; and rewashing the resultant gas with an acid solution of divalent mercury ions, the concentration of which ranges from 0.05 to 0.5g per liter, at room temperature and atmospheric pressure to obtain a purified gas containing mercury vapor of less than 0.01 mg/Nm.sup.3, that is, 0.001 ppm.

Abstract: Ethylbenzene is produced by the alkylation of benzene and subsequently catalytically dehydrogenated to produce styrene in a process wherein a benzene sidecut stream removed from the fractionation zone separating the newly produced ethylbenzene is water washed to remove a boron-containing complex. The washed sidecut stream is then utilized as the solvent stream fed to a liquid-liquid extraction zone which treats a water stream formed by condensing the effluent of a dehydrogenation zone. The treated water stream is used to generate steam and the extract stream removed from the extraction zone is combined with the effluent of the dehydrogenation zone to cool and dilute the effluent and to recover styrene and ethylbenzene.

Abstract: Carbon fibers having excellent properties are produced by a process which comprises thermal-stabilizing and carbonizing acrylonitrile fibers containing certain aminosiloxanes.

Abstract: The proposed contact method of producing sulphuric acid consists in that sulphur or pyrite is roasted, with the resulting gaseous mixture having a maximum moisture content of 0.02 percent by volume being treated in order to oxidize the sulphurous acid anhydride contained therein into sulphuric anhydride. Then, the sulphuric anhydride is absorbed from the gaseous mixture by a 92-98 percent sulphuric acid solution, which is taken in a quantity of 0.4 to 1.5 kg per kg of the gaseous mixture. The absorption process is carried out at a temperature from 30.degree. to 125.degree. C. The flow velocity of the gaseous mixture is 13 to 16 m/sec.

Abstract: A process for preparing hydrogen peroxide which comprises reacting hydrogen with oxygen in an aqueous medium containing a platinum-group catalyst, characterized in that the partial pressure of hydrogen and the partial pressure of oxygen in the gaseous phase of the reaction system are maintained at at least 0.5 atmosphere and at least 1.0 atmosphere respectively, and the platinum group catalyst is caused to be present in an amount, calculated as metal, of at least a minimum effective catalytic amount up to 30 mg per 100 ml. of said aqueous medium.

Abstract: The present invention relates to a process for wet-treating an exhaust gas which comprises simultaneously removing a nitrogen oxide (NO.sub.x) and a sulfur oxide (SO.sub.x) from an exhaust gas containing these oxides by treating exhaust gas containing oxides of nitrogen and sulfur with a lime or limestone slurry containing alkali metal or alkaline earth metal iodide.

Abstract: Styrene is removed from a recycle water stream of an ethylbenzene dehydrogenation process by liquid-liquid extraction to prevent polymer buildup on heat exchange tubes and to lower coke formation in boiler tubes. The water stream is then fed into a heater to form steam for use within the reaction zone of the process. The solvent used for the extraction is benzene or a normal paraffin and preferably is the overhead product of a benzene-toluene column which separates the products of the process. The use of extraction lowers utility costs compared to stripping the recycle water stream.

Abstract: A highly sorbent iron oxide for use in the purification of dilute sulfur and oxygen-bearing gases is prepared by a two step process which involves a low temperature decomposition of iron sulfate and a low temperature oxidation of the intermediate product.

Abstract: Process for extraction and separation of metals utilizing the advantages of liquid-liquid extraction with cation exchangers without requiring the equivalent addition of alkali. The process is based on a combination of leaching the metal-containing raw materials with an organic acid (cation exchanger) and a subsequent use of the formed metal cationic complex in a liquid-liquid extraction process. In the said extraction process, the organic solution of metal complexes is used to recover and separate metal ions from an aqueous solution of metal salts.

Abstract: A process for the production of monobasic potassium phosphate from wet process phosphoric acid and potassium sulfate by ion exchange. The application of the process is the production of monobasic potassium phosphate by ion exchange from wet phosphoric acid produced by the reaction of sulfuric acid on apatite rock and by-product potassium sulfate from processes for the recovery of aluminum from alunite.

Abstract: Nitrous oxide losses are reduced by bringing acid to weakly alkaline salt solutions or suspensions into media containing nitrous oxide or media which develop nitrous oxide.

Abstract: An aqueous regenerative SO.sub.2 scrubbing system is provided which has a scrubbing loop and a regeneration loop. The scrubbing loop contains a scrubber through which a thiosulfate-rich aqueous solution containing an alkali metal carbonate continuously circulates under sulfite-forming conditions. The sulfute in the spent absorbent solution is converted to thiosulfate in a sulfite conversion zone located in the scrubbing loop but outside the scrubber. The sulfite conversion is effected by means of a reducing agent containing a water soluble alkali metal hydrosulfite as the essential sulfite reducing agent. The regeneration loop serves to convert the incremental portion of thiosulfate formed in the scrubbing loop to H.sub.2 S and an aqueous solution containing the required amounts of alkali metal carbonate and of alkali metal hydrosulfide for the scrubbing loop.

Abstract: The separation of cobalt from nickel is enhanced by extracting aqueous solutions of the respective thiocyanates with a cyclic ketone, preferably isophorone.

Abstract: A substantially uniform, transparent, electrically conducting, metal oxide film (e.g. of indium/tin oxide) can be deposited on to a substrate such as glass of large lateral dimensions, e.g. a windscreen for an aircraft or a land vehicle, by low-pressure reactive sputtering from a cathode of the metal, using an atmosphere of oxygen and another gas or gases (preferably an inert gas) at reduced pressure, by providing access for the sputtering atmosphere to penetrate into the whole of the working space between the cathode and the substrate so as to maintain a substantial degree of uniformity in the oxygen concentration in the working space. Access for the atmosphere may be provided by means of passages extending through the cathode assembly, by dividing the cathode assembly into parallel strips separated by gaps, and the atmosphere may be supplied direct to the working space through such gaps. Relative movement is effected between the cathode assembly and the substrate, e.g.

Abstract: Elongated, polycrystalline particles of alpha iron oxide, characterized by an open, porous structure and consisting of hematite microcrystallites containing from 2 to 4 percent of sulfate are prepared by the reaction of lithium hydroxide and ferric sulfate in weakly acidic to neutral aqueous solution under at least autogenous pressures at temperatures in the range of 150.degree.-350.degree. C. The particles are readily converted to gamma iron oxide of good magnetic properites and also have utility as pigments and catalysts.

Abstract: Sulfate solutions containing at least one valuable metal from the group: Fe, Ni and Co, particularly solutions resulting from the leaching of lateritic ores or concentrates, are treated to recover the valuable metal. The latter is precipitated by treating the solution with magnesium hydroxide. The resulting magnesium-containing solution is treated with lime under controlled conditions to precipitate relatively fine particles of magnesium hydroxide and relatively coarse particles of gypsum. The difference in particle size is relied on to separate the magnesium hydroxide (for recycling) from the gypsum (which is calcined to regenerate lime).

Abstract: A method of absorbing SO.sub.2 by use of an absorbing medium containing ammonia compounds is described. In a process wherein sulfur bearing constituents are combusted, SO.sub.2 bearing flue gases are generated. Having been cooled, the flue gases are contacted in a multi-stage absorption system by aqueous absorbents comprised of ammonium compounds which are maintained so that SO.sub.2 is removed from the flue gas and the formation of the ammonium sulfite fume is inhibited.

Abstract: An adduct having the formula: 4Na.sub.2 SO.sub.4. 2H.sub.2 O.sub.2. NaCl, is prepared by reacting sodium sulfate with hydrogen peroxide in an aqueous solution, in the presence of sodium chloride in the reaction system.

Abstract: Organic acids are added to ammoniacal leach liquors containing base metals such as copper, nickel and cobalt. Ammonia and carbon dioxide are then stripped from the leach liquor by heating the leach liquor sufficiently to drive off the ammonia and carbon dioxide. The resulting loss of ammonia and carbon dioxide causes the pH of the leach liquor to drop and enables the metal values to load onto the organic acid. Metal values are selectively stripped from the loaded organic acid.

Abstract: A process for removing chlorine from a solution of zinc sulfate, in which the pH of the solution is reduced to below 2.6 with sulfuric acid. Cupric ions are established in the solution in an amount such that after removal of the chlorine by precipitation as cuprous chloride, there remains an excess of cupric copper in the solution which is greater than 0.5 g/l. The cupric ions can be added by adding cupric sulphate and zinc powder, or cupric salt and metallic copper, or cupric copper followed by cuprous oxide. The cuprous chloride precipitate is collected and washed and treated with sodium hydroxide in an amount to raise the pH to more than 7, thereby to precipitate cuprous oxide which is separated by filtration.