Abstract: A process is described for recovering calcium hypochlorite values from the filter media employed in the filtration of calcium hypochlorite slurries. Deposits of Ca(OCl).sub.2 along with insoluble materials adhering to the filter media are washed with an aqueous solution of calcium hypochlorite to form a slurry of calcium hypochlorite solids. Water is used to wash the filter media to dissolve any remaining Ca(OCl).sub.2 and form a solution of calcium hypochlorite. The slurry and solution are then admixed to provide a solution of calcium hypochlorite whose concentration is controlled within the range of from about 45 to about 215 grams per liter of Ca(OCl).sub.2. This solution is employed in the production of calcium hypochlorite and is recycled to the washing step.

Abstract: Alkali metal chlorites are produced by the reaction of chlorine dioxide with an alkali metal amalgam in a reaction mixture where the pH is maintained at from about 9.5 to about 11.5 by providing an excess of the alkali metal to the chlorine dioxide of at least 10 mole percent.Alkali metal chlorites obtained by this process are free of insoluble mercury and have reduced concentrations of soluble mercury as a contaminant.

Abstract: Novel compositions comprising calcium hypochlorite and a proportion of a polyacrylic acid compound have been produced. the compositions provide accurately controlled concentrations of available chlorine to bodies of water such as swimming pools by reducing the solubility off the calcium hypochlorite. In addition, when employing dispensers for water soluble chemicals in treating very hard or highly alkaline water, inhibition of scale formation and prevention of scale build-up in the dispenser is achieved when the novel compositions are used.

Abstract: Polychloroisocyanurate products are produced in a continuous process which reacts a cyanuric acid component with a chlorinating agent in a reaction mixture to which a purge gas is fed to remove in an effluent gas, any nitrogen trichloride produced along with other by-products. The effluent gas is fed to a gas analyzer such as a gas chromatograph which determines the concentration of NCl.sub.3 present and compares it with a predetermined upper limit. If this upper limit is equalled or exceeded, the gas analyzer activates means to flood the reaction mixture with purge gas to prevent explosive amounts of nitrogen trichloride from being present in the reaction mixture. The gas analyzer may also control the feed rate of the cyanuric acid component and the chlorinating agent.The pH of the reaction mixture is also continuously measured in a pH analyzer having means to control the flow rate of the purge gas and reactants should the predetermined pH limits for the reaction be attained or exceeded.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride solutions in elecrolytic diaphragm cells is comprised of a mixture of sand and a thermoplastic polymeric binding agent. The diaphragms may include a support material and an additive such as a lubricant. The diaphragms of the present invention have increased stability, a long operational life and are non-polluting.

Abstract: A method of restoring elasticity to heat sealed portions of an elecrolytic diaphragm comprised of a perfluorosulfonic acid resin in the alkali metal ion form comprises contacting the heat sealed sections with an aqueous fluid.

Abstract: An electrode is described which is comprised of an electroconductive substrate having an exterior surface of perovskite of the emperical formulaA A' B 0.sub.3 (I)a. wherein A is lanthanum,B. wherein A' is an alkaline earth metal selected from the group consisting of calcium, strontium, barium, and mixtures thereof,C. wherein B is a transition metal selected from the group consisting of cobalt, chromium, tungsten, molybdenum, manganese, iron, nickel, rhenium, uranium, and mixtures thereof,D. wherein the atomic ratio of A:A' is in the range from about 0.05:1 to about 0.95:1,E. wherein the valence of A + A' + B = 6,f. wherein said electrode has a resistivity preferably less than about 10 milliohm-centimeters.sup.-1, andG. wherein said perovskite is substantially insoluble in the electrolyte contacting said electrode under typical conditions of electrolysis.

Abstract: A process for the production of dibasic magnesium hypochlorite comprises the reaction of a solid magnesium salt and a solid hypochlorite where one of the solid reactants is in the hydrate form. The process produces dibasic magnesium hypochlorite with excellent recovery of chlorine values and with reduced requirements for the disposal of solutions containing available chlorine.Dibasic magnesium hypochlorite, Mg(OCl).sub.2 . 2 Mg(OH).sub.2 is useful in bleaching and sanitizing applications.

Abstract: Electrolysis of alkali metal chloride solutions to produce chlorine and alkali metal hydroxides is accomplished in a cell comprising an anode compartment, a cathode compartment, a cation permeable divider separating the anode compartment from the cathode compartment, where the anode compartment contains a porous metal separator. The porous metal separator is comprised of a porous plate of, for example, a valve metal having a porosity of from about 30 to about 75 percent and an air flow value of from about 0.1 to about 60 CFM. The anode separator is positioned in the anode compartment so it is spaced apart from the cation permeable divider and from the anode. During electrolysis, an alkaline brine zone is formed between the porous metal separator and the cation permeable divider which increases the service life of the cation permeable divider. In addition, the porous metal separator provides improved chlorine gas separation properties.

Abstract: Current efficiency in an electrolytic membrane cell for the production of potassium hydroxide from aqueous solutions of KCl is considerably increased by maintaining the anolyte concentration of KCl at 250-350 grams per liter and the catholyte concentration of KOH at from about 410 to about 480 grams per liter. The electrolytic cell employs a cationic permselective membrane comprised of a hydrolyzed copolymer of a perfluoroolefin and a fluorosulfonated perfluorovinyl ether.

Abstract: The electrolysis of alkali metal chloride solutions in a diaphragm cell having an anode compartment separated from a cathode compartment by a porous perfluorosulfonic acid resin diaphragm is optimized by maintaining the pH of the alkali metal chloride solution in the range of from about 3.0 to about 5.0. In this pH range, highly desirable bulk flow properties are obtained by controlling the dimensional stability of the perfluorosulfonic acid resin.

Abstract: Trichloroisocyanuric acid is produced by the reaction of a symmetrical triazine compound selected from the group consisting of ammelide, chlorosubstituted ammelide, ammeline and chlorosubstituted ammeline, with dichlorine monoxide in a gaseous mixture with a diluent gas. The gaseous mixture is comprised of from about 1 to about 30 percent by volume of dichlorine monoxide.

Abstract: A process is described in which granular calcium hypochlorite particles are encapsulated with at least one layer of a hydrated low melting inorgnaic salt. In this process granular calcium hypochlorite particles are lifted from a moving bed to the upper part of a distribution zone and the lifted particles are released to fall downwardly through the upper portion to the moving bed. A molten hydrated low melting inorganic salt is sprayed onto the falling particles above the moving bed, and the coated particles are cooled to provide at least one solid outer layer of said low melting hydrated inorganic salt.

Abstract: Novel compositions comprising calcium hypochlorite and a hydrazide of a monocarboxylic acid containing from about 10 to about 24 carbon atoms have been produced. The compositions provide accurately controlled concentrations of available chlorine to bodies of water such as swimming pools by reducing the solubility of the calcium hypochlorite.

Abstract: A highly conductive and corrosion resistant low hydrogen overvoltage cathode. The cathode comprises a copper substrate plated with an alloy of nickel, vanadium, and molybdenum.

Abstract: A porous anode separator for an electrolytic cell for the electrolysis of alkali metal chloride solutions comprises a porous valve metal plate having an electrochemically active coating on the face and a barrier layer on the back and on a portion of the interior. The barrier layer comprises a mixture of a valve metal oxide with a ceramic oxide. Suitable ceramic oxides include those of silicon, aluminum, magnesium, and calcium. The electrochemically active coating comprises a platinum group metal or metal oxide. The porous anodes provide improved gas separation and permit a substantial reduction in the amount of platinum group metal required for the electrochemically active coating.

Abstract: A container cover is provided which prevents young children from gaining access to the container's contents. The container has an opening at one end and a latch lip adjacent to the opening. The cover comprises a plate having at least one opening and a handle secured to the plate and having at least two grips, a releasing grip and a non-releasing grip. Two latching means secure the plate to the latch lip, one of the latching means is attached to the releasing grip and passes through the plate opening. The releasing grip has means for releasing the latching means such as lifting, sliding or rotating.The container may be used for containers for materials which may be harmful if handled or ingested.A particular application of the cover is on a magazine for soluble solids to be dissolved by a liquid, for example, in treating swimming pool water. The magazine is a component of an apparatus for dissolving and dispensing soluble material including a container having an upper and a lower chamber.

Abstract: An improved progressing cavity pump of the Moineau type having a helically externally threaded rotor coacting with an internally helically threaded stator. In a Moineau pump where the pump casing is a singular tubular unit, the stator is bonded to the casing with an adhesive. When the pumps are used with a corrosive fluid, such as caustic soda, the adhesive is attacked and the stator becomes free to rotate. To prevent the stator from rotating, a rib is attached along a portion of the casing. The rib restrains the stator and prevents its rotation.

Abstract: An electrolytic cell of the type having a plurality of anodes and at least one foraminous cathode. The cell includes an anode mounting plate to which the anodes are connected. The anodes have associated therewith a mounting post which is attached to the anode mounting plate of the cell by attaching means which can be used to vary the spacing between the anodes for reception of the cathodes. The attaching means includes a crank member which, upon rotation thereof, moves the mounting posts laterally with respect to the anode mounting plate.

Abstract: A method for the measurement of amounts of free available halogen in solution which is independent of the pH has been developed. The method comprises providing a sensing electrode having a porous conductive component and a reference electrode in a measuring zone, and connecting a potential measuring means between the sensing electrode and the reference electrode. An aqueous solution containing an available halogen is introduced into the measuring zone to contact the sensing electrode and the reference electrode. A pH control solution is passed through at least a portion of the porous conductive component. The free available halogen concentration is measured and indicated on the potential measuring means.Employing the method, residual amounts of an oxidizing or reducing agent in solution can be continuously measured, independent of the pH of the solution. In addition, the electrode surface is continuously cleansed by the pH control solution.