Abstract: Stable compositions of calcium hypochlorite containing selected hydrated inorganic salts having a sufficiently high enthalpy and the ability to provide water release to sufficiently quench reactions and reduce the potential for conflagration.

Abstract: Describes a composition comprising a mixture of calcium hypochlorite and hydrated magnesium sulfate having an average of from 3 to 5.5 moles of water of hydration per mole of magnesium sulfate. The amount of hydrated magnesium sulfate in the composition is such that the composition has at least a DOT Packing Group III Division 5.1 Classification.

Abstract: Stable compositions of calcium hypochlorite containing selected hydrated inorganic salts having a sufficiently high enthalpy and the ability to provide water release to sufficiently quench reactions and reduce the potential for conflagration.

Abstract: Stable compositions of calcium hypochlorite containing selected hydrated inorganic salts having a sufficiently high enthalpy and the ability to provide water release to sufficiently quench reactions and reduce the potential for conflagration.

Abstract: A system and method are disclosed for increasing the concentration of hypochlorous acid in a quantity of water. Acid is injected into chlorinated water to decrease the pH of the chlorinated water. By decreasing the pH, the hypochlorite/hypochlorous acid equilibrium of the chlorinated water is shifted to increase the concentration of hypochlorous acid on the treated water.

Abstract: A non-Division 5.1 Oxidizer composition consisting essentially of a blend of hydrated calcium hypochlorite with magnesium sulfate heptahydrate, wherein the blend contains at least about 17% by weight of water based on the total weight of the blend.

Abstract: An economical, industrial and ecologically-sound process for producing high test hypochlorite and a calcium chloride aqueous solution comprising the steps of (a) preparing milk of lime, (b) chlorinating the milk of lime to crystallize calcium hypochlorite dihydrate in the presence of the prismatic calcium hypochlorite dihydrate seed crystals having a specific habit to prepare a slurry of coarse calcium hypochlorite dihydrate crystals, (c) separating the slurry into a wet cake of calcium hypochlorite dihydrate crystals and a mother liquor containing calcium hypochlorite and calcium chloride, (d) drying the wet cake to provide high test hypochlorite, and (e) adding hydrochloric acid to the mother liquor or bringing the mother liquor into contact with an oxide of at least one of Mn, Fe, Co, Ni, Cu, and Pd to decompose the calcium hypochlorite to obtain a calcium chloride aqueous solution.

Abstract: A process of preparing alkylene oxides comprises steps of: (1) optionally forming a hypochlorite solution; (2) contacting chlorine with a solution of a hypochlorite below about 60.degree. C., and a pH of less than about 5.5, with sufficient micromixing to achieve a product hypochlorous acid in a yield of at least about 80 percent; (3) separating at least a portion the hypochlorous acid from an aqueous metal chloride solution wherein the solution is sprayed as droplets; (4) distilling the remaining liquid phase; (5) absorbing the hypochlorous acid and dichlorine monoxide in low-chlorides water to produce a low-chlorides aqueous hypochlorous acid solution; (6) contacting the low-chlorides aqueous hypochlorous acid solution with an olefin in a continuous process to form a olefin chlorohydrin; (7) optionally contacting the olefin chlorohydrin with a base to form a alkylene oxide and a salt solution; and (8) optionally separating the alkylene oxide from the salt solution.

Abstract: A hydrated calcium hypochlorite agglomerated particle is provided that is produced in a turbine agglomerator and has a plurality of connecting links of recrystallized material bridging the small particles forming the agglomerate which has therein a plurality of pores created by the substantial evaporation of the layer of surface liquid. The surface tension and adhesion forces of the layer of surface liquid at least partially holds the agglomerated particle together prior to drying.

Abstract: Compositions consisting essentially of calcium hypochlorite and a water soluble zinc salt, the compositions containing from about 40 percent to about 99 percent by weight of calcium hypochlorite, provide controlled release of the components for continuous and effective sanitation and algae control to waters treated for use in swimming pools and spas.

Abstract: A process and apparatus utilizing the process of the present invention are provided to produce a fast dissolving, thermally sensitive granular product. The process employs a fluidized spray dryer having a fluidized bed of granular particles into which recycled off-sized product is fed after being agglomerated to adjust particle size. The spray dryer optionally can employ a second nozzle positioned above the fluidized bed. The process can be employed in the production of calcium hypochlorite water sanitizing chemical wherein the chlorine is supplied from a hypochlorous acid reactor and lime hypochlorinator.

Abstract: A hydrated calcium hypochlorite agglomerated particle is provided that is produced in a turbine agglomerator and has a plurality of connecting links of recrystallized material bridging the small particles forming the agglomerate which has therein a plurlaity of pores created by the substantial evaporation of the layer of surface liquid. The surface tension and adhesion forces of the layer of surface liquid at least partially holds the agglomerated particle together prior to drying.

Abstract: A calcium hypochlorite composition consists essentially of at least 75 percent by weight of Ca(OCl).sub.2, from about 6 to about 14 percent by weight of water, and less than 1.5 percent by weight of an alkali metal chloride. The novel composition provides increased amounts of sanitizing and disinfecting to, for example, water bodies while remaining safe with respect to thermal decomposition. Further, the composition reduces the rate of chlorine evolution during storage.

Abstract: A process and apparatus utilizing the process of the present invention are provided to produce a fast dissolving, thermally sensitive granular product. The process employs a fluidized spray dryer having a fluidized bed of granular particles into which recycled off-sized product is fed after being agglomerated to adjust particle size. The spray dryer optionally can employ a second nozzle positioned above the fluidized bed. The process can be employed in the production of calcium hypochlorite water sanitizing chemical wherein the chlorine is supplied from a hypochlorous acid reactor and lime hypochlorinator.

Abstract: Granular calcium hypochlorite containing from about 0.001 to about 1.0 weight percent of finely-divided polyfluorinated polymer, e.g., polytetrafluoroethylene, dispersed throughout the granules is described. The product may be compressed and formed into shaped articles, e.g., tablets. The granules may be prepared by admixing the polyfluorinated polymer with particulate calcium hypochlorite, compacting the mixture and granulating the compacted product. Tablets prepared from the polyfluorinated polymer containing granular calcium hypochlorite dissolve in water at a rate slower than tablets prepared without the polyfluorinated polymer. Finely-divided calcium hypochlorite powder, e.g., powder of less than about 10 microns in size, is rendered more conveyable and compactible by the addition of the finely-divided polyfluorinated polymer; and mixtures of finely-divided calcium hypochlorite powder and particulate calcium hypochlorite is rendered more readily compactible.

Abstract: Granular calcium hypochlorite containing from about 0.001 to about 1.0 weight percent of finely-divided polyfluorinated polymer, e.g., polytetrafluoroethylene, dispersed throughout the granules is described. The product may be compressed and formed into shaped articles, e.g., tablets. The granules may be prepared by admixing the polyfluorinated polymer with particulate calcium hypochlorite, compacting the mixture and granulating the compacted product. Tablets prepared from the polyfluorinated polymer containing granular calcium hypochlorite dissolve in water at a rate slower than tablets prepared without the polyfluorinated polymer. Finely-divided calcium hypochlorite powder, e.g., powder of less than about 10 microns in size, is rendered more conveyable and compactible by the addition of the finely-divided polyfluorinated polymer; and mixtures of finely-divided calcium hypochlorite powder and particulate calcium hypochlorite is rendered more readily compactible.

Abstract: A granular calcium hypochlorite composition comprising a particle of calcium hypochlorite dihydrate and/or calcium hypochlorite anhydride, the surface of which has been covered with a double decomposition product of calcium hypochlorite and an alkali metal hydroxide. This composition is prepared by adhering an aqueous alkali metal hydroxide solution to the particle of calcium hypochlorite dihydride or calcium hypochlorite anhydride, and the drying the particle.

Abstract: Granular calcium hypochlorite containing from about 0.001 to about 1.0 weight percent of finely-divided polyfluorinated polymer, e.g., polytetrafluoroethylene, dispersed throughout the granules is described. The product may be compressed and formed into shaped articles, e.g., tablets. The granules may be prepared by admixing the polyfluorinated polymer with particulate calcium hypochlorite, compacting the mixture and granulating the compacted product. Tablets prepared from the polyfluorinated polymer containing granular clacium hypochlorite dissolve in water at a rate slower than tablets prepared without the polyfluorinated polymer. Finely-divided calcium hypochlorite powder, e.g., powder of less than about 10 microns in size, is rendered more conveyable and compactible by the addition of the finely-divided polyfluorinated polymer; and mixtures of finely-divided calcium hypochlorite powder and particulate calcium hypochlorite is rendered more readily compactible.

Abstract: Disclosed is a granular calcium hypochlorite composition having a calcium hypochlorite content of at least 55 wt. % and composed of particles having an ellipsoidal shape in section, wherein at least 50 wt. % of the ellipsoidal particles have a short diameter of 0.3-5 mm, a long diameter of 0.5-20 mm, and a long diameter/short diameter ratio larger than 1.5 but not larger than 5. This composition is prepared by a process wherein a wet calcium hypochlorite composition comprising at least 40 wt. % of calcium hypochlorite and 25-45 wt.% of water is extruded through a die having an orifice diameter of 0.3-5 mm; the extrudate is cut to a length of 0.5-20 mm so that the length/orifice diameter ratio is larger than 1.5 but not larger than 5 to form columnar shaped particles; the columnar shaped particles are subjected to rolling granulation; and the resulting granules are dried until the water content is reduced to 4-22 wt. %.

Abstract: An aqueous sodium hypochlorite solution (3) is added, in a quantity which is deficient relative to that required to decompose the entire amount of calcium chloride, to an aqueous calcium chloride solution (2), the sodium chloride which precipitates (6) is separated and the remaining amount (9) of the sodium hypochlorite solution is then added to the resulting mother-liquor (7). Single FIGURE.

Abstract: A process for preparing chlorinated lime solid having an available chlorine ontent in the range of about 30 to about 50 weight percent by contacting a chlorine source, e.g., liquid chlorine, with a basic calcium-containing substance, e.g., hydrated lime, in the presence of water or aqueous calcium chlorine at a pH to produce an aqueous slurry having available chlorine content in the range of about 13 to 17 weight percent and a pH in the range of about 10.6 to 10.9 and containing an aqueous solution and a chlorinated lime precipitate combined with separating said slurry into an aqueous solution and a chlorinated lime precipitate having less than about 40 to 50 percent water combined with drying said chlorinated lime precipitate to produce chlorinated lime solid having the desired available chlorine content is disclosed.

Abstract: A continuous process for producing granular calcium hypochlorite particles comprises admixing lime and an aqueous liquid in a mixing zone to form a lime slurry. The lime slurry is fed into a crystallizing zone along with a calcium hypochlorite-containing liquid to produce a slurry of coarse dibasic calcium hypochlorite crystals and to elutriate a fines slurry from the crystallizing zone. The coarse dibasic calcium hypochlorite crystals are separated from a dibasic hypochlorite mother liquor and fed to a chlorinating zone. Reaction of the coarse dibasic calcium hypochlorite crystals with a chlorinating agent is conducted to produce a slurry of hemibasic calcium hypochlorite crystals. The slurry is fed to a separator to separate a hemibasic hypochlorite mother liquor from the hemibasic calcium hypochlorite crystals.

Abstract: A process to decolorize and stabilize nitro compounds by contacting the nitro compound with an alkaline earth metal hypochlorite particulate material.

Abstract: A rapidly dissolving granular hydrated calcium hypochlorite product is comprised of hydrated calcium hypochlorite particles having at least 95 percent of the particles within a size range of from about 300 to about 850 microns. The product has a packed bulk density of less than about 1.05 grams per cubic centimeter. When dispersed on the surface of a body of water, such as a swimming pool, at least 3 feet deep, about 70 weight percent or higher of the particles dissolve within one minute.

Abstract: Residual hypochlorite contained in chlorinated slurries of either carbonaceous gold-containing ores or mixtures of carbonaceous and oxide gold-containing ores are reduced by reaction with sulfide ion-providing chemical compounds preferably sodium hydrosulfide, sodium sulfide or hydrogen sulfide. The hypochlorite "kill" step enables subsequent cyanide leach operations to be conducted more efficiently.

Abstract: A rapidly dissolving granular hydrated calcium hypochlorite product is comprised of hydrated calcium hypochlorite particles having at least 95 percent of the particles within a size range of from about 300 to about 850 microns. The product has a packed bulk density of less than about 1.05 grams per cubic centimeter. When dispersed on the surface of a body of water, such as a swimming pool, at least 3 feet deep, about 70 weight percent or higher of the particles dissolve within one minute.

Abstract: This invention discloses a stable, surfactant-free, aqueous hypochlorite paste readily dispersible in hot or cold water, thickened with non-reactive inorganics without having alkali metal silicates, providing up to 10% available chlorine and with a viscosity ranging from about 25,000 to about 2,000,000 CPS.

Abstract: Crystals of dibasic calcium hypochlorite are produced by reacting lime with a solution containing hypochlorite ions under conditions suitable to produce large crystals of dibasic calcium hypochlorite, a mother liquor and fine insoluble impurities and separating the large dibasic calcium hypochlorite crystals from the mother liquor and insoluble impurities.

Abstract: A process for producing calcium hypochlorite hydrate crystals, which comprises continuously supplying a basic calcium hypochlorite slurry and chlorine gas, and reacting them at a temperature of from 20.degree.-50.degree. C. and at a chlorination rate of from 92 to 98.5% to precipitate calcium hypochlorite crystals at a crystallization velocity of not greater than 200 kg/m.sup.3 per hour.

Abstract: The subject of the invention is a two-stage process for the production of bleaching powder with a high active chlorine content, which comprises suspending slaked lime in the aqueous solution resulting from the second chlorination stage after the separation of the solid formed therein, passing chlorine gas into the suspension at 35.degree.-45.degree. C. until the lime content of the suspension has been reduced to between 40% and 55% by weight of the initial content, separating the mother liquor from the solid obtained, suspending the solid in water in a ratio of from 1 to 1.5 parts of water per part of solid, bringing the pH of the suspension obtained to between 13 and 14 with an aqueous sodium hydroxide solution, passing gaseous chlorine into the suspension at a temperature of about 10 C.

Abstract: A continuous process for producing granular calcium hypochlorite particles comprises admixing lime and an aqueous liquid in a mixing zone to form a lime slurry. The lime slurry is fed into a crystallizing zone along with a calcium hypochlorite-containing liquid to produce a slurry of coarse dibasic calcium hypochlorite crystals and to elutriate a fines slurry from the crystallizing zone. The coarse dibasic calcium hypochlorite crystals are separated from a dibasic hypochlorite mother liquor and fed to a chlorinating zone. Reaction of the coarse dibasic calcium hypochlorite crystals with a chlorinating agent is conducted to produce a slurry of hemibasic calcium hypochlorite crystals. The slurry is fed to a separator to separate a hemibasic hypochlorite mother liquor from the hemibasic calcium hypochlorite crystals.

Abstract: Neutral calcium hypochlorite is made by producing and separating out from the mother liquor crystals of dibasic calcium hypochlorite; reacting the dibasic calcium hypochlorite with a solution free of insoluble impurities and containing hypochlorite ions to produce hemibasic calcium hypochlorite crystals; separating the crystals of hemibasic calcium hypochlorite from the mother liquor; and converting the hemibasic calcium hypochlorite crystals into neutral calcium hypochlorite.

Abstract: A process for producing calcium hypochlorite comprises wetting lime with an aqueous slurry of fine basic calcium hypochlorite crystals in a mixing zone to form an aqueous lime slurry. The aqueous lime slurry is reacted with a calcium hypochlorite solution in a crystallizing zone to produce a slurry of basic calcium hypochlorite crystals. The slurry of basic calcium hypochlorite crystals is separated in a first separation means into a slurry of fine basic calcium hypochlorite crystals and a slurry of coarse basic calcium hypochlorite crystals. The slurry of fine basic calcium hypochlorite crystals is returned to said mixing zone. The slurry of coarse basic calcium hypochlorite is conveyed to a second separation means to separate coarse crystals of basic calcium hypochlorite from a calcium hypochlorite mother liquor. Coarse crystals of basic calcium hypochlorite are admixed with lime and an alkali metal hypochlorite in a third mixing zone to form a mixed alkali slurry.

Abstract: Dibasic calcium hypochlorite scale present on the surfaces of process equipment, e.g., process vessels, used for the manufacture of neutral calcium hypochlorite is removed chemically by controllably adding chlorine to the process liquor under conditions of agitation while maintaining the pH of the process liquor at at least 7, e.g., from about 7 to about 10.5, thereby to solubilize the dibasic calcium hypochlorite scale without producing substantial amounts of elemental chlorine. In a preferred embodiment, the process liquor in the process equipment containing the dibasic calcium hypochlorite scale is forwarded to a further process vessel containing other less alkaline process liquor to which the chlorine is controllably added. The resulting hydrochloric acid-containing process liquor is recycled to the process equipment containing the dibasic scale and this procedure continued until the desired amount of dibasic calcium hypochlorite scale is solubilized.

Abstract: Dibasic calcium hypochlorite scale found on the surfaces of process equipment used for the manufacture of calcium hypochlorite is removed chemically by submerging the scale in water, thereby to form an aqueous alkaline solution, and controllably adding hydrochloric acid to the alkaline solution under conditions of agitation and while maintaining the pH of the solution at at least 7, thereby to solubilize the dibasic calcium hypochlorite scale without producing substantial amounts of elemental chlorine.

Abstract: Calcium hypochlorite is produced by admixing a slurry of lime containing soluble impurities with a saturated calcium hypochlorite solution in a crystallizing zone. An impure slurry of coarse and small dibasic calcium hypochlorite crystals and fine insolubles in a mother liquor is formed and fed to the intermediate section of a separation zone. An aqueous sodium chloride elutriant is fed to the lower section of the separation zone to separate a slurry of fine insolubles, which is conveyed in the elutriant to the upper section of the separation zone, and small crystals of dibasic calcium hypochlorite, which can be recycled to the crystallizing zone or destroyed by chlorination, from the dibasic calcium hypochlorite solution. A slurry of purified coarse dibasic calcium hypochlorite crystals in the elutriant is removed from the lower section of the separation zone at a rate controlled to maintain a rising velocity in the lower section of the separation zone of from about 0.5 to about 7 centimeters per minute.

Abstract: Calcium hypochlorite particles and larger sodium chloride crystals are separated by passing an aqueous slurry containing such particles and crystals into a first classification zone comprising a two-stage substantially vertical elutriator-classifier. A first slurry in which the solid phase is predominantly calcium hypochlorite particles is removed from the upper stage of the first classification zone. A second slurry in which the solid phase is predominantly sodium chloride crystals is removed from the lower stage of the first classification zone and forwarded to a second classification zone comprising a two-stage substantially vertical elutriator-classifier. A slurry in which the solid phase is predominantly calcium hypochlorite particles is removed from the upper stage of the second classification zone and, in one embodiment, combined with overflow from the upper stage of the first classification zone.

Abstract: Calcium hypochlorite particles and larger separable sodium chloride crystals produced in a process for manufacturing calcium hypochlorite are effectively separated by use of a staged upward-flow elutriator-classifier. In particular, an aqueous slurry of the calcium hypochlorite particles and sodium chloride crystals are introduced into about the midpoint of the classifier and elutriated with fluid substantially saturated in calcium hypochlorite and sodium chloride. A first slurry in which the solid phase is predominantly calcium hypochlorite, e.g., at least 95 weight percent, is removed as overflow from the top of the classifier, and a second slurry in which the solid phase is predominantly sodium chloride is removed as underflow from the bottom of the classifier.In one embodiment, the first slurry is separated into a wet cake of calcium hypochlorite and bleach mother liquor, a portion of which liquor is used as elutriating fluid.

Abstract: A process for producing calcium hypochlorite from lime containing insoluble impurities comprises reacting the lime with an aqueous solution of hypochlorous acid to form a reaction mixture comprised of coarse dibasic calcium hypochlorite crystals and fine insolubles comprised of fine dibasic calcium hypochlorite crystals, insoluble impurities, and unreacted lime. Coarse dibasic calcium hypochlorite crystals are separated from the reaction mixture, leaving a slurry comprised of an aqueous calcium hypochlorite solution containing fine insolubles. The slurry of fine insolubles is separated and the resulting clarified aqueous calcium hypochlorite solution is used to wash occluded fine insolubles from the coarse dibasic crystals. The resulting wash solution is combined with fine insolubles and the resulting slurry is reacted with hypochlorous acid and filtered to remove insoluble lime impurities.

Abstract: A process for producing neutral calcium hypochlorite comprises admixing lime, an alkali metal hypochlorite and dibasic calcium hypochlorite crystals in a mixing zone slurry. The mixing zone slurry is reacted with chlorine to form a paste of neutral calcium hypochlorite. The paste is then separated into a cake of neutral calcium hypochlorite and a paste liquor. A slurry of lime is fed to a crystallizer to react with the paste liquor to form a slurry of dibasic calcium hypochlorite crystals in a mother liquor. Crystals of dibasic calcium hypochlorite are then separated from the dibasic mother liquor and recycled to the mixing zone. The process of the present invention provides an efficient method of recovering calcium hypochlorite values from process liquors while reducing energy costs expended in the recovery. The process further provides rapid recovery of dibasic calcium hypochlorite for reuse in a neutral calcium hypochlorite process by optimizing separation rates.

Abstract: A process for making calcium hypochlorite from caustic soda calcium hydroxide and chlorine by feeding to a stirred reactor an aqueous solution of the total required amount of caustic soda and an aqueous suspension of up to 80% by weight of the total required amount of calcium hydroxide, passing chlorine through the mixture until a redox potential of 650 to 800 mV is reached and while continuing chlorination adding the remaining of the calcium hydroxide at such rate with respect to chlorine that redox potential gradually increases to between 850 and 950 mV. This process prevents thickening and caking which are a recognized problem with conventional batch processes.

Abstract: A continuous integrated process for the production of neutral calcium hypochlorite in which crystals of by-product sodium chloride are more easily separated from the calcium hypochlorite product is described. The process includes diluting an aqueous slurry of sodium hydroxide, lime and bleach mother liquor with aqueous salt solution saturated with calcium ion and sodium chloride and chlorinating the resulting aqueous admixture in the presence of a seed bed of sodium chloride crystals and calcium hypochlorite crystals at temperatures less than 35.degree. C., e.g., 15.degree.-20.degree. C. A suspension of readily separable, sodium chloride crystals and calcium hypochlorite crystals in chlorinator liquor is conveyed to a classification zone where the sodium chloride and calcium hypochlorite crystals are separated.

Abstract: Calcium hypochlorite is made by passing chlorine through an aqueous solution of alkali metal hydroxides containing suspended particles of calcium hydroxide, said alkali metal hydroxides consisting of sodium hydroxide and an hydroxide of an alkali metal having an atomic weight higher than that of sodium.

Abstract: A process for producing neutral calcium hypochlorite which comprises reacting an aqueous slurry of lime containing insoluble impurities with chlorine to form a first slurry of dibasic calcium hypochlorite crystals and insoluble impurities. The insoluble impurities are separated from the first slurry by employing separation means for classifying solids with respect to particle size. Dibasic calcium hypochlorite crystals are then separated and admixed with an alkali metal hypochlorite and recycle dibasic calcium hypochlorite crystals to form a mixing zone slurry. This slurry is reacted with chlorine to form a paste of neutral calcium hypochlorite. The paste is separated into a cake of neutral calcium hypochlorite and a paste liquor and the cake of neutral calcium hypochlorite recovered. The paste liquor is reacted with lime to form a second slurry of dibasic calcium hypochlorite crystals which are separated from their mother liquor and returned to the mixing zone as recycle dibasic calcium hypochlorite.

Abstract: A process for the continuous preparation of a slurry of calcium hypochlorite wherein a solution of sodium hydroxide is fed to one end of an elongated tubular reaction and a calcium hydroxide slurry and chlorine are introduced through a number of injection sites along the length of the reactor. The redox potential of the reaction mixture at any injection site must not be inferior to that at the immediately preceding site and must be in the range 900 to 950 mV at the exit end of the reactor. The process permits easy control of the reaction temperature and of the viscosity of the reaction mixture.

Abstract: A stable calcium hypochlorite composition and a method for the preparation thereof. The composition has a calcium hypochlorite anhydride and/or a calcium hypochlorite dihydrate used as main constituent and comprises at least 60 wt % of calcium hypochlorite; at least 5 wt % of calcium hydroxide; at least 4 wt % of water content; and 5 wt % or less of than that calcium chloride. The composition is stable and decomposes only in a less degree at a high temperature and during storage over a long period.

Abstract: A novel process for the production of granular calcium hypochlorite compositions is provided which comprises reacting neutral calcium hypochlorite with an alkaline solution comprised of an alkali metal hypochlorite and an alkali metal hydroxide. The reaction produces a slurry from which a wet cake comprised of neutral calcium hypochlorite and a residual amount of hemibasic calcium hypochlorite is recovered and dried. During the drying process in which granular calcium hypochlorite compositions are obtained, there is a substantial reduction in the loss of available chlorine from the product.

Abstract: In a process for preparing granular calcium hypochlorite particles, wherein hydrated triple salt crystals of calcium hypochlorite, sodium hypochlorite, and sodium chloride are reacted with a chlorinated lime slurry to form particles of calcium hypochlorite dihydrate, the resulting slurry is processed to separate the calcium hypochlorite dihydrate particles and the resulting particles are dried to form granular calcium hypochlorite particles, the improvement which comprises:a. continuously feeding triple salt crystals and a chlorinated lime slurry to a paste reactor containing an aqueous paste slurry of calcium hypochlorite dihydrate particles to form additional aqueous paste slurry of calcium hypochlorite dihydrate particles,b. continuously removing a portion of the paste slurry from the paste reactor,c. continuously dividing the removed portion of paste slurry into a first part and a second part,d. continuously recycling said first part of the paste slurry to the paste reactor,e.

Abstract: A continuous integrated process for the production of calcium hypochlorite in which crystals of by-product sodium chloride are more easily separated for the calcium hypochlorite product is described. The process includes: (a) introducing with agitation into a vessel an aqueous slurry of dibasic calcium hypochlorite, sodium hydroxide, and aqueous salt solution saturated with calcium ion and sodium chloride in amounts at least sufficient to substantially dilute the sodium hydroxide; (b) forwarding the resulting aqueous mixture of step (a) to a chlorination zone containing a seed bed of calcium hypochlorite and sodium chloride crystals; (c) introducing chlorine into the chlorination zone, thereby producing an aqueous suspension containing further quantities of calcium hypochlorite crystals and readily separable significantly larger sodium chloride crystals; and (d) removing aqueous suspension containing such calcium hypochlorite and sodium chloride crystals from the chlorination zone to a classification zone.

Abstract: A process for preparing hypochlorous acid in a sweep reactor is described in which gaseous chlorine is passed rapidly across the surface of an agitated aqueous solution of .[.alkali metal.]. .Iadd.sodium .Iaddend.hydroxide at a reduced temperature. The resulting gaseous product mixture of hypochlorous acid, chlorine monoxide, and unreacted chlorine is conveyed from the reactor to a suitable scrubber to produce an aqueous hypochlorous acid solution.The aqueous reaction product of the sweep reactor is a suspension of .[.alkali metal.]. .Iadd.sodium .Iaddend.chloride in .[.alkali metal.]. .Iadd.sodium .Iaddend.hypochlorite, which is withdrawn and filtered to separate the solid. The clarified aqueous solution of .[.alkali metal.]. .Iadd.sodium .Iaddend.hypochlorite is reacted with the aqueous hypochlorous acid solution from the scrubber, chlorine and lime to form an aqueous slurry of calcium hypochlorite.