Abstract: A process is described for the production of dibasic magnesium hypochlorite which comprises reacting a magnesium salt with an aqueous slurry of a crystalline hypochlorite salt in a reaction mixture containing a chloride ion source. The aqueous slurry has a solids content of from about 10 to about 90 percent by weight of a hypochlorite salt such as an alkali metal hypochlorite or calcium hypochlorite. The process provides a dibasic magnesium hypochlorite product which is readily separated.Dibasic magnesium hypochlorite, Mg(OCl).sub.2.2Mg(OH).sub.2 is useful in bleaching and sanitizing applications.

Abstract: An electrolytic cell for the electrolysis of aqueous solutions to produce gaseous products is comprised of a housing, a separator traversing said housing to form an anode compartment and a cathode compartment, an anode in the anode compartment, a cathode in the cathode compartment, means for introducing an electrolyte into and removing said electrolyte from said anode compartment, an outlet for gaseous products in the anode compartment, means for introducing a liquid into and removing a liquid from the cathode compartment, and an outlet for gaseous products in the cathode compartment. The electrolytic cell has at least one of the anode and the cathode comprising a porous electrode having a porosity in the range of from about 30 to about 98 percent, the porous electrode having a first portion in direct contact with the separator and a second portion spaced apart from the separator, the second portion being closer to said outlets for gaseous products than said first portion.

Abstract: Hydrated alkali metal dichloroisocyanurate particles are prepared in a process which comprises, in a first step, spraying droplets of an aqueous slurry of alkali metal dichloroisocyanurate into an evaporation zone fed with a moving stream of heated gas to evaporate water from the droplets and form dry porous solid spherical particles of hydrated sodium dichloroisocyanurate. In a second step, the dry particles are fluidized in a cooling gas until cooled to a temperature below about 50.degree. C. The resulting porous hydrated particles have a uniform distribution of hydration, are dust-free, and quickly dissolve in water.

Abstract: An electrode for use in the electrolysis of aqueous solutions of ionizable compounds is produced by a method which comprises affixing filaments to a support fabric to form a network of filaments. An electroconductive metal is deposted on the filaments to form metal coated filaments. During the metal deposition, interfilament bonding takes place at contact sites between adjacent filaments. Removing the support fabric from the metal coated filament network produces a reticulate electrode having a porosity of at least about 80 percent. The three dimensional electrodes are highly conductive, have high internal surface area, and are mechanically strong.

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: Cyanuric acid is produced in a process in which a solution of urea or biuret is pyrolyzed by contacting the solution with a heated gas at temperatures which substantially pyrolyze urea or biuret while concurrently evaporating the solvent.The novel process simplifies solvent recovery, reduces solvent losses and has reduced requirements for processing equipment.

Abstract: Layered glass batch pellets are produced in a continuous process which comprises the steps of:(a) maintaining in the pelletizing zone of a rotary apparatus a moving bed of recycle pellets,(b) feeding sand and particles of a calcium carbonate source into the pelletizing zone,(c) feeding a Na.sub.2 O source comprised of a solution of sodium hydroxide into the pelletizing zone, the recycle pellets being coated with a layer comprised of the solution of sodium hydroxide, the sand and the calcium carbonate source and forming layered pellets,(d) passing the layered pellets into a heated drying zone to form dried layered pellets, the dried layered pellets having a residual moisture content of from about 4 to about 12 percent by weight,(e) passing the dried layered pellets from the drying zone to a recycle zone,(f) recycling a portion of the dried layered pellets to the pelletizing zone as the recycle pellets, and(g) recovering a portion of the dried layered pellets from the recycle zone.

Abstract: A process for stabilizing in situ soluble mercury in deposits of mercury-containing materials which comprises treating the deposits with a stabilizing amount of an inorganic sulfur compound. Suitable inorganic sulfur compounds include sulfides, alkali metal thiosulfates, alkaline earth metal thiosulfates, iron thiosulfates, alkali metal dithionites, and alkaline earth metal dithionites. These inorganic sulfur compounds react with soluble mercury to convert it to insoluble mercury compounds and substantially inhibit its removal by elution with water from the deposits of mercury-containing material.The process may be used to treat land areas, landfill deposits, or submarine sediment deposits to reduce soluble mercury concentrations to a few parts per billion.

Abstract: Silver coated particles having high concentrations of metallic silver are produced which are useful in forming alloys with metals such as mercury. The process comprises admixing carrier particles with an aqueous solution of a silver salt to form a slurry. A hydrazine compound is added to the slurry to precipitate metallic silver on the carrier particles in a medium which becomes increasingly acidic. Silver coated particles having a metallic silver content up to 90 percent by weight of the coated particle can be produced in a single impregnation under conditions which prevent the formation of explosive by-products such as silver nitride. The silver coated particles are particularly suitable for the recovery of metals such as mercury from fluids.

Abstract: A current distributor for an electrode for an electrolytic cell for the electrolysis of aqueous solutions of ionic compounds is provided which comprises an electrically conductive material having a front surface comprised of a plurality of electrode-engaging means projecting from it for attachment to a foraminous electrode. The rear surface of the current collector is suitable for attachment to an electrical conductor. The novel current distributors are particularly suitable for use with reticulate electrodes.

Abstract: A novel briquet is comprised of compressed hydrated calcium hypochlorite particles having a calcium hypochlorite content in the range from about 55 to about 75 percent by weight, a water content in the range from about 4 to about 10 percent by weight and a compression strength of from about 2 to about 95 kilograms. The briquets may be used in sanitizing water supplies as they dissolve slowly to release available chlorine at a controlled rate.

Abstract: A process for the recovery of calcium chloride hydrates and calcium chlorate compounds comprises:(a) blending an effluent comprised of an aqueous solution of calcium chloride, calcium chlorate, and calcium hypochlorite and having a weight ratio of Ca(ClO.sub.3).sub.2 /CaCl.sub.2 of less than about 0.2 with a second mother liquor comprised of an aqueous solution of calcium chlorate and calcium chloride and having a weight ratio of Ca(ClO.sub.3).sub.2 /CaCl.sub.2 of greater than about 1.0 to form a blended solution;(b) feeding the blended solution to a first crystallizer to form a slurry of calcium chloride hydrate in a first mother liquor;(c) separating the crystals of calcium chloride hydrate from the first mother liquor, the first mother liquor having a weight ratio of Ca(ClO.sub.3).sub.2 /CaCl.sub.2 of at least about 1.

Abstract: Calcium chloride hydrates are recovered from calcium hypochlorite process effluents comprised of an aqueous solution of calcium chloride, calcium hypochlorite, and calcium chlorate in a process which comprises acidifying the effluent with a chlorine-containing compound selected from the group consisting of chlorine, hydrochloric acid and hydrogen chloride to form an acidic aqueous solution of calcium chloride having reduced concentrations of calcium hypochlorite. Water is evaporated from the acidic aqueous solution to produce a concentrated acidic aqueous solution containing at least 45 percent by weight of calcium chloride. The concentrated acidic aqueous solution of calcium chloride is fed to a crystallizer to form crystals of a calcium chloride hydrate. The calcium chloride hydrate crystals are separated from a mother liquor and recovered.The process is used to produce calcium chloride hexahydrate, calcium chloride tetrahydrate or calcium chloride dihydrate.

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 process is disclosed for purifying aqueous solutions of metal hydroxides.An aqueous solution of a metal hydroxide, such as sodium hydroxide, containing a complex of a heavy metal contaminant, such as mercury, is heated.An oxidizing agent, such as hydrogen peroxide, is reacted with the solution to precipitate solid particles of an oxide of the heavy metal, for example, mercuric oxide, in a solution. The solid particles of mercuric oxide are separated from the solution by filtration.The purified solution comprised of water and sodium hydroxide and containing less than about 0.3 part per million mercury by weight is sold commercially. The solid particles of mercuric oxide are landfilled or otherwise utilized.

Abstract: A novel electrode for a monopolar filter press cell is disclosed which comprises a first foraminous surface and a second foraminous surface positioned in parallel and spaced apart, which are secured to conductor rods positioned in a cell frame. The frame has two side members, a top member and a bottom member attached to the first and second foraminous surfaces. A chamber is formed between the first and second foraminous surfaces and bounded by the frame. At least one pair of conductor rods pass through one of the side members of the frame into the chamber. One of the conductor rods in each pair is attached only to the first foraminous surface; the other conductor rod in the pair is attached only to the second foraminous surface. The frame has inlets and outlets for introducing fluids into and removing electrolysis products from the chamber.

Abstract: An electrode for a monopolar filter press cell comprises two vertical foraminous surfaces positioned in parallel and spaced apart. A frame having two side members, a top member, and a bottom member is attached to the foraminous surfaces. A chamber is formed between the foraminous surfaces and bounded by the frame. Conductor rods pass through one of the side members into the chamber; the conductor rods being spaced apart from the foraminous surfaces. The frame has inlets and outlets for introducing fluids into and removing electrolysis products from the chamber. The novel electrodes provide improved gas flow patterns by creating limited restrictions within the chamber so as to generate a Venturi or low pressure effect which pulls gases from the interelectrode gap through the electrode surfaces and into the chamber.

Abstract: A current conductor assembly for conducting electric current to electrodes in cells for the electrolysis of a salt solution is comprised of a conductor and a nonconductive casing for the conductor. There is a space between the conductor and the casing with an inlet in the casing for receiving a fluid. The conductor assembly has means for supplying a pressurized fluid to the space between the conductor and the casing; means for sealingly attaching one end of the conductor assembly to the electrodes, where this end is immersed in the salt solution; and a compressible sealing assembly for the opposite end of the conductor assembly comprised of a compression means and a sealing means.The conductor assembly employs the pressurized fluid to prevent corrosive attack of the conductor metal should a leak develop in the conductor assembly.

Abstract: An electrolytic cell employing a hydraulically impermeable membrane having a spacing means interposed between the anode and the membrane, is operated by providing a positive pressure differential between the cathode compartment and the anode compartment. The pressure differential is sufficient to maintain contact between the spacer and the membrane to provide uniform spacing between the anode and the membrane. In addition, this process provides sufficient spacing between the membrane and the cathode to provide efficient release of any gas formed and to prevent gas blinding at the cathode. Employing the positive pressure differential enables the cell to be operated at reduced energy costs when producing, for example, concentrated solutions of sodium hydroxide by careful control of the spacing between the membrane and the electrodes.