...During the Civil War, the Confederacy established its own Patent Office which issued 266 patents, a third of which concerned implements of war.
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| Number | Title | Issue Date |
| 7052669 | Process for production of ammonium thiosulphate A process for continuous production of ammonium thiosulphate, (NH4)2S2O3 (ATS) from NH3, H2S and SO2 is disclosed. A first feed stream comprising H2O, H2S and NH3... | 05/30/2006 |
| 7022504 | Method for the bacterially assisted heap leaching of chalcopyrite A method for the bacterially assisted heap leaching of chalcopyrite includes providing a chalcopyrite containing ore heap to oxidize sulphide minerals therein, the heap containing and/or being inoculated with a sulphide oxidizing bacterial culture that either does n... | 04/04/2006 |
| 6680039 | Sulfite treatment of spent industrial wastes A method of treating metal-contaminated spent foundry sand, or other industrial waste, by combining the sand with a sulfite to produce insoluble metal sulfur oxide complexes that do not leach from the sand. The treated waste may also be processed to reduc... | 01/20/2004 |
| 6555078 | Method of preparing lithium salts The present invention provides an inexpensive process for the preparation of lithium salts of formula LiX having a desired or required level of purity using lithium chloride and lithium sulfate. In the process of the invention, a lithium salt selected fro... | 04/29/2003 |
| 6214313 | High-purity magnesium hydroxide and process for its production Magnesium hydroxide of high purity, having a fine particle size suitable for use in flame retardants and other high-end uses, is produced by utilizing flue gas desulfurization system process slurry as feedstock; the production process is absent energy-int... | 04/10/2001 |
| 5976868 | Process for the treatment of gases An installation and a method are described for the treatment of a gas containing hydrogen sulphide, the gas (1) being washed in a first gas scrubber (5) with an alkaline wash liquid and the spent wash liquid (4) being treated in an aerobic reactor (6) wit... | 11/02/1999 |
| 5941037 | Oxygen scavenging hydrotalcite and compositions containing same An oxygen scavenging agent and compositions capable of providing good oxygen absorption capabilities which contain said agent, wherein the agent is a modified anionic hydrotalcite particulate material.... | 08/24/1999 |
| 5861133 | Synthetic chalcoalumite compounds and process for producing thereof A synthetic chalcoalumite compound represented by the formula (1) (Zna-x2+ Mx2+)Al43+ (OH)b (An-)c.mH.sub.2 O (1) wherein M2+... | 01/19/1999 |
| 5827488 | Process for removing SO2 and NOx from a gaseous stream A process for removing both sulfur dioxide and nitrogen oxides from a gaseous stream where the stream is contacted in a first wet scrubbing unit with an alkaline earth compound to remove sulfur dioxide and humidify the gaseous stream, passing of the humid... | 10/27/1998 |
| 5777058 | Metallo-oxomeric scrubber compositions Scavengers for removing acidic or corrosive gaseous components from semiconductor process effluents comprising a metallic macromer comprising a coordinated complex of (i) metal coordination atoms linked to (ii) oxomeric moieties selected from the group co... | 07/07/1998 |
| 5567406 | Manufacturing clear potassium sulfite Disclosed is a method of manufacturing potassium sulfite from a potassium hydroxide feedstock. A feedstock is tested for the presence of iron and, if the feedstock contains less than 0.3 ppm of iron, it is reacted with sulfur dioxide in an aqueous solutio... | 10/22/1996 |
| 5399323 | Method for improving reducing potential of natural gas feed A means to increase the reducing potential of natural gas used in the reduction of sulfates such as gypsum. A reducing mixture of natural gas and air (or oxygen) is heated prior to reduction of the sulfate. For gypsum reduction, heating the reducing mixtu... | 03/21/1995 |
| 5273727 | Flue gas purification and production of dry ammonium bisulfites and bisulfates A system is provided for converting flue gas pollutants to useful dry or concentrated ammonium bisulfite and ammonium bisulfate byproducts and other harmless byproducts, and for collecting the useful byproducts. The system also removes particulate materia... | 12/28/1993 |
| 5266296 | Cocurrent flow process for the manufacture of sodium sulfite and bisulfite solutions Sodium (bi)sulfites are produced by the steps of: (a) introducing a stream of aqueous sodium carbonate into the top end of a main packed column reactor; (b) introducing a stream of sulfur dioxide gas into the top end of the main packed column reactor concurren... | 11/30/1993 |
| 5262143 | Production of finely divided particulate siliceous material by decomposition of alkali metal silicate with sulfitic species Production of siliceous precipitates, for example sodium aluminosilicates by decomposition of an alkali metal sulfite solution with a solution of a sulfitic species such as sulfur dioxide, sulfurous acid or a salt thereof. Precipitates having excellent pr... | 11/16/1993 |
| 5246679 | Addition of organophosphonates for size control of wet calcium-based FGD byproduct solids under inhibited oxidation conditions A process for producing large, regularly-shaped crystalline calcium sulfite solids in a wet calcium-based flue gas desulfurization system is provided. A chemical crystal modifier, preferably an organophosphonate, is added to the calcium sulfite-containing... | 09/21/1993 |
| 5098679 | Purification of alkali metal hydrosulfite solutions A process for treating an alkali metal hydrosulfite solution which comprises contacting the alkali metal hydrosulfite solution with aluminum in a reaction mixture, and admixing carbon dioxide gas with the reaction mixture to remove dissolved aluminum as a... | 03/24/1992 |
| 5077023 | Reduction in the rate of oxidation of sulfite solutions The rates of oxidation of sulfite/bisulfite-containing solutions in gas-liquid scrubbers for removing SO2 from gases are reduced by adding oxidation inhibitors to the solutions in an amount of from 0.02 to 20 mmol per hour and per square meter ... | 12/31/1991 |
| 5034202 | Removal of thiosulfate from hydrosulfite solutions A process for treating an alkali metal hydrosulfite solution which comprises contacting the alkali metal hydrosulfite solution, having a residual alkalinity of from about 1 to about 20 grams per liter of hydroxide ion, with aluminum. The process of the in... | 07/23/1991 |
| 5019365 | Quaternary polyamines as sulfite oxidation inhibitors Inhibitors of oxidation of sulfites to sulfates in sulfur dioxide scrubbing solutions are disclosed. The inhibitors are cationic polyelectrolytes which are water soluble, have a molecular weight of at least 10,000 daltons and contain quaternary amine grou... | 05/28/1991 |
| 4960575 | Removal of hydrogen sulfide with on site generated sulfite from geothermal steam Geothermal steam is condensed with a sulfite solution to abate hydrogen sulfide. A portion of the hydrogen sulfide is converted in the condensation in the presence of soluble cationic polymeric catalysts to soluble sulfur compounds while avoiding elementa... | 10/02/1990 |
| 4937056 | Process for obtaining high purity magnesium compounds from magnesium containing materials Processes for the selective leaching of magnesium-containing solids, which contain calcium and/or heavy metals, and the selective precipitation and crystallization of the leached magnesium are provided. The leaching is conducted with aqueous sulphur dioxi... | 06/26/1990 |
| 4900524 | Method for separation of sulfur dioxide from gases To prevent the formation of encrustations on a pH sensor in a combustion exhaust or flue gas washing apparatus, alkaline additives are added to the wash water which, upon contacting SO2 in the gases, form sulfite particles. The sulfite particle... | 02/13/1990 |
| 4844880 | Process for the manufacture of sodium metabisulfite An improved process for the manufacture of sodium metabisulfite is provided. In this process, the chemical reaction forming sodium bisulfite solution is carried out separately from the crystallization of sodium metabisulfite. The crystallization step is c... | 07/04/1989 |
| 4810483 | Process for producing anhydrous alkali metal hydrosulfites A process for producing an anhydrous alkali metal hydrosulfite comprises contacting hydrate crystals of an alkali metal hydrosulfite with an alkaline aqueous solution of a dehydrating agent having a pH of at least about 7. The slurry formed is maintained ... | 03/07/1989 |
| 4708856 | Liquid-gas absorption process A process for absorbing SO2 from a gas in a packed column employs a low aqueous sulfite feed rate of 0.05 to 1 gallon per minute per square foot of tower cross section, or preferably 0.1 to 0.3 gallons per minute per square foot. Lower capital ... | 11/24/1987 |
| 4687648 | Sodium-limestone double alkali flue gas desulfurization process with improved limestone utilization A method for improving utilization of limestone in a sodium-limestone double alkali flue gas desulfurization process. Spent alkaline absorber solution, containing sodium sulfite and sodium bisulfite, is diverted for regeneration treatment in a series of s... | 08/18/1987 |
| 4685935 | Process for producing pure magnesium sulphite A process for producing a pure magnesium sulphite from crude crystalline magnesium sulphite. Into a full suspension or flow containing magnesium sulphite crystals at least one further water-containing and heat-supplying flow is led. The heat-supplying flo... | 08/11/1987 |
| 4668485 | Recovery of sodium aluminate from Bayer process red mud A process for recovery of valuable products from Bayer process red mud comprises the steps: (a) digesting red mud with sulphur dioxide in the presence of water to dissolve soda, alumina and silica therein; (b) heating the product of step (a), with or with... | 05/26/1987 |
| 4649033 | Process to eliminate air pollutants which result from the combustion of fuels containing sulphur Process to eliminate air pollutants which result from the combustion of fuels containing sulphur, permitting the transformation of substantially all the existing SO2 and SO3 produced by the combustion of fuels to ammonium sulphate.... | 03/10/1987 |
| 4540556 | Dual alkali scrubber liquor regeneration with production of gypsum A process for the recovery of gypsum as a product of a dual alkali system for regeneration of a sodium base alkaline scrubber liquor in which the liquor reacts with ground limestone in two serially connected sludge blankets containing from 15%-40% solids ... | 09/10/1985 |
| 4508688 | Method of regenerating acetate in a metal removal process A process for separating lead includes the steps of dissolving a water insoluble lead salt in an acetate solution and precipitating the lead by treating the acetate solution with a sulfite so as to form an insoluble lead sulfite. The acetate is recovered ... | 04/02/1985 |
| 4481074 | Process for the preparation of a sodium sulphite containing liquor The method relates to a process in the preparation of the cooking liquor for sodium sulphite pulp for carrying out a reaction between sodium bisulphite and sodium bicarbonate and/or sodium carbonate by bringing solutions containing said compounds into con... | 11/06/1984 |
| 4474740 | Method for regenerating physically acting organic scrubbing agents Method and apparatus for regenerating physically acting organic scrubbing agents laden with sulfur dioxide and/or sulfur trioxide and eventually carbon dioxide in the course of a gas purification process. Equipment costs and energy losses are reduced by a... | 10/02/1984 |
| 4474737 | Process of purification of magnesic raw material Process of purification of magnesic raw material. Sulphur dioxide is allowed to react with an aqueous suspension of calcinated magnesite, crude or contaminated magnesium oxide, magnesium hydroxide, hydrated magnesium carbonates, or crude crystals of magne... | 10/02/1984 |
| 4469663 | Scale control in flue gas desulfurization An improvement in a process for flue gas desulfurization in which particular phosphonomethylated derivatives of aminoethylpiperazine, employed as threshold agents, prevent calcium scale formation in the contacting section but permit precipitation of calci... | 09/04/1984 |
| 4462969 | Regeneration of sulfur dioxide scrubber liquor A process of regeneration of scrubber bleed liquor discharged from SO2 gas scrubber in which there are provided two serially connected sludge blankets containing 15-40% finely divided solids in liquor overlain by a relatively clear supernatant ... | 07/31/1984 |
| 4454101 | Dewatering of flue gas desulfurization sulfite solids The dewatering capabilities of sulfite sludges from flue gas desulfurization facilities are substantially improved by the addition of relatively small amounts of sodium thiosulfate additive, or additives derived from or related to sodium thiosulfate, into... | 06/12/1984 |
| 4431615 | Process for the recovery of magnesium and/or nickel by liquid-liquid extraction The recovery of substantially pure magnesium and/or nickel sulphite which is present in a solid starting meterial. The latter is treated with gaseous SO2 in water, the solution obtained is treated by a liquid-liquid extraction, to give an aqueo... | 02/14/1984 |
| 4425313 | Removal and recovery of nitrogen and sulfur oxides from gaseous mixtures containing them A cyclic process for removing lower valence nitrogen oxides from gaseous mixtures includes treating the mixtures with an aqueous media including alkali metal carbonate and alkali metal bicarbonate and a preoxygen oxidant to form higher valence nitrogen ox... | 01/10/1984 |