Abstract: The present invention provides a process for the manufacture of sodium hydroxide and sodium chloride products from a waste brine stream containing sodium chloride, and at least sodium carbonate or sodium bicarbonate. The method of this invention comprises converting the sodium carbonate and/or sodium bicarbonate to sodium hydroxide through addition of lime to the brine, while simultaneously converting impurities to less soluble forms to facilitate their removal. The causticized brine is separated from unreacted lime, calcium carbonate and solid impurities to produce clean brine with reduced levels of impurities. The brine is then concentrated by evaporation, forming relatively pure sodium chloride crystals, which are extracted and rinsed to reduce alkali contaminants.
Abstract: A hydrogen gas generation system for vehicles and stationary power applications comprises a trio of rigid, cylindrical high pressure reservoir tanks interconnected with suitable fittings and pipelines. A water holding tank alternatively stores hydroxide solution, or transfers it to an adjacent gas generating tank, containing a plurality of tubular, aluminum fuel rods. When the holding tank is suitably pressurized, hydroxide solution is transferred into the generating tank to start a reaction with a plurality of elongated, tubular aluminum rods disposed therewithin. Conversely, the liquid contents of the generating tank can be forcibly pressured back into the holding tank to stop the gas generation reaction. High pressure hydrogen gas is humidified in the third tank prior to combustion as fuel. Humidified hydrogen is transferred via control valves to the application.
Abstract: Alkali metal alkoxides are prepared by reacting alkali metal amalgam with alcohol in the presence of a catalyst comprising iron having a carbon content of at least 0.3% by weight.
Type:
Grant
Filed:
September 28, 2001
Date of Patent:
December 2, 2003
Assignee:
BASF Aktiengesellschaft
Inventors:
Kerstin Schierle-Arndt, Hans-Josef Sterzel, Dieter Schläfer, Josef Guth, Holger Friedrich, Peter Zehner
Abstract: Disclosed is a method of denuding a sodium-mercury amalgam to recover mercury therefrom and produce a sodium alcoholate. The amalgam is reacted with a C.sub.1 to C.sub.4 alcohol in the presence of a catalyst selected from the group consisting of tungsten carbide, iron treated high density carbon, iridium, ruthenium, and mixtures thereof. The resulting sodium alcoholate is separated from the mercury.
Type:
Grant
Filed:
January 21, 1992
Date of Patent:
November 16, 1993
Assignee:
Occidental Chemical Corporation
Inventors:
Robert G. Adams, Tilak V. Bommaraju, Sharon D. Fritts
Abstract: In a purification process for brine, impurities such as calcium, magnesium and/or sulphate are precipitated by the addition of calcium hydroxide (Ca(OH).sub.2) and sodium carbonate (Na.sub.2 CO.sub.3). Following NaCl crystallization by evaporation of the brine, a mother liquor is obtained which still contains among others sulphate, potassium and bromide ions. Further concentration of this mother liquor by evaporation results in the precipitation of both NaCl and Na.sub.2 SO.sub.4 and a more strongly concentrated mother liquor with respect to both potassium and bromide remains. This concentrated mother liquor is drained off. Either the precipitated NaCl and Na.sub.2 SO.sub.4 are dissolved in water or the Na.sub.2 SO.sub.4 is dissolved in purified brine or crude brine and then returned to the brine purification process, thereby lowering both the potassium and bromide ion levels in the purified brine. As a consequence the contents of both potassium and bromide of the NaCl are reduced.
Abstract: Methods are described for the low temperature preparation of the spinel LiMn.sub.2 O.sub.4 and layered LiCoO.sub.2 phases which are intercalable compounds of interest for use in lithium secondary batteries. These phases can be prepared in bulk or thick film form at temperatures less than 400.degree. C. using acetate precursors.
Type:
Grant
Filed:
April 30, 1992
Date of Patent:
May 18, 1993
Assignee:
Bell Communications Research, Inc.
Inventors:
Philippe Barboux, Frough K. Shokoohi, Jean-Marie Tarascon
Abstract: A process of recausticizing kraft green liquor in which the green liquor containing sodium carbonate is passed in a stream in admixture with particles comprising slaked lime, in which stream the liquid phase becomes progressively weaker in sodium carbonate and stronger in sodium hydroxide. Lime is added in order to provide a continuous supply of slaked lime for reaction with the sodium carbonate, and the stream is passed to a solids/liquid separator which recovers liquid phase from said stream, strong in NaOH, continuously and separately from the solid phase of the stream, as white liquor. The rate of the recausticizing reaction is limited by the rate of diffusion of carbonate ion into the solid particles, and of hydroxyl ion out of the solid particles. Typically, these rates limit the amount of causticizing achieved to less than the equilibrium value.
Type:
Grant
Filed:
December 3, 1985
Date of Patent:
May 26, 1987
Assignees:
Canadian Patents and Development Ltd., Sandwell and Company Limited
Abstract: In a process for purifying raw brine containing dissolved strontium, calcium and magnesium impurities wherein the raw brine is treated by contacting the brine with sodium carbonate for precipitation of strontium and calcium carbonate, contacting the brine containing the strontium and calcium carbonate solids with sodium hydroxide for precipitation of magnesium hydroxide, and removing strontium carbonate, calcium carbonate and magnesium hydroxide solids from the sodium chloride brine, the improvement which comprises passing at least a portion of said removed solids to the zone wherein the raw brine is contacted with sodium carbonate.