Abstract: Apparatus and process for analyzing the nitrogen trichloride concentration in gases containing it utilizing an ultraviolet light source. Unabsorbed filtered light collected from the sample at a wavelength of about 218 nm is compared with a standard at a wavelength of about 260 nm and the resultant is expressed in terms of nitrogen trichloride concentration.

Abstract: A novel process for purifying an alkaline solution of a lower alkyl alcohol containing as an impurity an alkali metal alkoxide, an alkali metal hydroxide, and water is disclosed. The process comprises treating the alkaline solution of a lower alkyl alcohol with an anhydrous hydrogen halide to react with the alkali metal alkoxide and the alkali metal hydroxide to provide a neutral solution comprised of the lower alkyl alcohol, an alkali metal halide and water. The alkali metal halide is removed from the neutral solution to obtain a substantially salt-free solution comprised of the lower alkyl alcohol and water. A zeolite molecular sieve is contacted with the solution to remove the water and to recover a substantially anhydrous solution of a lower alkyl alcohol. The process produces purified substantially anhydrous alcohol solutions suitable for the use in the production of alkali metal alkoxides such as sodium methoxide without introducing undesired amounts of alkaline impurities into the product.

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 oxide source into the pelletizing zone,(c) feeding 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 oxide source and forming layered pellets,(d) passing the layered pellets into a heated drying zone exposed to an atmosphere containing carbon dioxide gas,(e) lifting the layered pellets to the upper part of the drying zone and releasing the layered pellets to separately fall through the drying zone,(f) simultaneously absorbing carbon dioxide onto the layered pellets while evaporating and removing water from the falling layered pellets to form dried layered pellets, the dried layered pellets having a residual moisture content of less than 15 percent by weight,

Abstract: A method and apparatus for in situ reduction of cathode overvoltage in electrolytic cells. The method involves introducing low overvoltage or noble metal ions into the catholyte solution and plating those ions on the cathode in situ. The apparatus includes a low overvoltage or noble metal ion generating device for introducing low overvoltage or noble metal ions into the cathode solution so as to plate them in situ on the cathode during or prior to cell operation.

Abstract: A method is provided for sealing portions of cation exchange membranes of carboxylic acid type fluorinated polymers. The portions of the membranes to be sealed are in the ester form of the membrane and are ultrasonically sealed at sealing times of from about 0.1 to about 5 seconds while employing power in the range of from about 50 to about 600 watts.The novel method of the present invention can be used to repair membranes of carboxylic acid type fluorinated polymers which have been torn, slit, or cut. Sections of membrane materials may be sealed together to form an enlarged or reinforced membrane. The sealed portions are substantially free of wrinkles and are not mechanically damaged or weakened.

Abstract: A diaphragm for electrolytic cells for the electrolysis of aqueous salt solutions is comprised of a porous portion and an impervious portion. The impervious portion is comprised of a fabric layer attached to an impervious film layer. A thermoplastic fabric material is used as the porous portion which is impregnated with a siliceous composition as the electrolytically active component.

Abstract: An improved cathode with a conductive metal core and a Raney-type catalytic surface predominantly derived from an adherent ternary aluminide intermetallic crystalline precursory outer portion of the metal core is disclosed. The precursory outer portion preferably has molybdenum and titanium added to give a precursor alloy having the formula Ni.sub.x Mo.sub.y Ti.sub.z Al.sub.3 where x is within the range of from about 75 to about 94 weight percent, y is within the range of from about 5 to about 20 weight percent and z is within the range of from about 1 to about 5 weight percent of the Ni-Mo-Ti portion of the alloy. Also disclosed is a method of producing a low overvoltage cathode. The method includes the steps of taking a Ni-Mo-Ti core or substrate having about 5-20 weight percentage of Mo and about 1-5 weight percent Ti and coating it with aluminum then heat treating to form a Ni-Mo-Ti-Al ternary alloy with mostly NiAl.sub.

Abstract: A method of heat sealing together two untreated layers of a sulfonated perfluorovinyl ether ion exchange diaphragm or membrane material having pendant groups predominantly in the sulfonamide form by placing a layer of untreated sulfonated perfluorovinyl ether material having pendant groups predominantly in the sulfonic acid form between the sulfonamide layers to create a "sandwich". The preferred heat sealing involves applying from 1 to 5, and preferably from 3.5 to 5.0 kg/cm.sup.2 pressure at from 260.degree. to 350.degree. C. and preferably from 280.degree. to 320.degree. C. for from 3.5 to 7.5, and preferably from 3.5 to 5.0 seconds to this "sandwich". It had been previously taught that such untreated sulfonamide layers could not be heat sealed together. The novel heat sealing technique of this invention enables fabrication of a cathode-membrane unit using ion exchange membranes having such a sulfonamide layer facing the cathode of an electrolytic cell.

Abstract: A diaphragm for use in the electrolysis of aqueous solutions of ionizable compounds in electrolytic diaphragm cells is comprised of a support fabric impregnated with particles of an inorganic clay of the montmorillonite group.The diaphragms are physically and chemically stable, provide reduced cell voltages during operation of the cell and having increased operational life.

Abstract: A process for reducing calcium ion concentration in alkaline alkali metal chloride brines containing an alkali metal hydroxide is disclosed. The process comprises admixing an alkali metal bicarbonate with the alkaline brines to form an insoluble calcium salt, removing the insoluble calcium salt from the brine, and recovering a purified alkali metal chloride brine having reduced calcium ion concentration.The process produces alkali metal chloride brines suitable for use in electrolytic diaphragm cells while substantially reducing the amount of acid required to neutralize the brines.

Abstract: Rounded granular calcium hypochlorite comprised of a core of calcium hypochlorite encapsulated with a plurality of rounded layers of calcium hypochlorite, wherein the core of each particle generally has a diameter which ranges from about 200 to about 2,000 microns and the novel coated granules have a diameter ranging from about 400 to about 5,000 microns. Each layer is formed from an aqueous slurry of calcium hypochlorite which contains a high percentage of soluble inorganic salts as well as calcium hypochlorite. These soluble salts impart a high degree of cohesive bonding as each layer is formed and result in rounded granules of higher density and improved dust resistance.

Abstract: A method and composition are described for the decomposition of sodium-mercury amalgam in a reactor containing solid packing particles to form hydrogen, sodium hydroxide, and denuded mercury. The novel packing particles are comprised of a heterogeneous solid mixture of a matrix of a thermally stable polymer having embedded therein discrete particles of a surface active element. Suitable thermally stable polymers include polyphenylene sulfide and suitable surface active elements include carbon, iron, nickel, cobalt, vanadium, and molybdenum. The proportion of polymer in the packing generally ranges from about 20 to about 80 percent by volume. Preferably, the matrix is prepared in porous form which may also be coated with a surface active metal.

Abstract: A process for the start-up of membrane cells for the electrolysis of an aqueous salt solution for cells having an anode compartment containing a plurality of anodes, a cathode compartment containing a plurality of cathodes and an ion exchange membrane separating the anode compartment from the cathode compartment is comprised of the steps of:(a) feeding simultaneously the aqueous salt solution to the anode compartment and a liquid to the cathode compartment while maintaining substantially equal pressure on the membrane from each of the compartments,(b) increasing the pressure on the membrane from the anode compartment,(c) increasing the pressure on the membrane from the cathode compartment, and(d) cyclically repeating steps (b) and (c) during the start-up period.The novel process reduces wrinkling and eliminates cracking of the membrane during the start-up period of, for example, a cell for the electrolysis of alkali metal chloride brines for the production of chlorine and alkali metal hydroxides.

Abstract: A process for removing dissolved halogen gas and oxyhalide ions from an aqueous alkali metal halide solution containing them which comprises reacting said aqueous alkali metal halide solution with an inorganic peroxide, and adjusting the pH of said aqueous alkali metal halide solution to a pH within the range from about 6 to about 11 with an inorganic base, whereby a purified alkali metal halide solution of reduced concentration of said dissolved halogen gas and oxyhalide ions is produced.

Abstract: A process for the concentration of spent brine from the membrane electrolytic cell which comprises removing spent brine containing dissolved chlorine from the membrane electrolytic cell, feeding the spent brine to a concentration zone, applying microwave energy to the spent brine to produce concentrated brine and a gaseous mixture of chlorine and steam, feeding the concentrated brine and the gaseous mixture to a separation zone, separating the gaseous mixture from the concentrated brine, and returning the concentrated brine to the membrane electrolytic cell.Process reduces the operating and equipment costs while effectively recovering chlorine and brine values.

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 method has been devised for removing hexavalent chromium from concentrated aqueous alkali metal chlorate solution by reacting the solution with an inorganic sulfur containing compound and separating divalent and trivalent chromium compounds from the solution. Alkali metal hypohalites may be simultaneously removed from the chlorate solution by reaction with excess inorganic sulfur containing compound.

Abstract: A method is provided for producing liquid permeable diaphragms for an electrolytic cell having a plurality of foraminous electrodes and a space between each pair of adjacent electrodes. The method comprises covering the foraminous electrodes with a liquid permeable thermoplastic support fabric and contacting the covered electrodes with a slurry of an electroactive material. Roller means are placed in the space between the pair of electrodes, the roller means comprising two rollers spaced apart, each of the rollers contacting only one of the pairs of electrodes, and moving the roller means to force the electroactive material into the liquid permeable thermoplastic support fabric whereby liquid permeable diaphragms are produced.

Abstract: Current efficiency in an electrolytic membrane cell for the production of concentrated potassium hydroxide is considerably increased by employing in the electrolytic membrane cell a membrane selected from a group consisting of an amine modified perfluorosulfonic acid membrane such as a primary amine, diamine, or polyamine modified perfluorosulfonic acid membrane, and a laminated perfluorosulfonic acid acid membrane, and a laminated perfluorosulfonic acid membrane comprised of at least two unmodified perfluorosulfonic acid membranes of different thickness and different equivalent weight.

Abstract: An improvement in the manufacture of flexible densified polyurethane foam wherein the partially cured freely risen foam is fed through a crush conveyor to minimize the density gradient throughout the vertical cross section. The crush conveyor includes an upper crushing section which is arcuate and has a radius of a dimension such that the ratio of the radius of the arc to height of the partially cured freely risen foam is 1.1 to 1 or greater. The crush conveyor has a bottom crushing section which may be arcuate with a radius of a dimension such that the ratio of its radius to the height of the partially cured freely risen foam is also 1.1 to 1 or greater. The radius of the bottom arcuate crushing section may be the same or larger than the radius of the top arc. As an alternative, the bottom crushing section may be planar and may be horizontal, or inclined with respect to the horizontal.