Abstract: It is now possible to desulfurize gases containing appreciable carbon dioxide proportions by limiting the production of carbon oxysulfide to a very low level, by treating these gases with adsorbents composed of very small, partially calcic zeolite A crystals agglomerated by clays containing low levels of iron and having reduced acidity and basicity. These clays may be obtained by phosphatization of montmorillonite, bentonite, attapulgite, or kaolin.
Type:
Grant
Filed:
November 22, 1994
Date of Patent:
March 11, 1997
Assignee:
Vniigaz
Inventors:
Albert M. Tsybulevski, Vladimir I. Mourine, Dominique Plee, Francis Mayolet
Abstract: A collapsed composition is described which is substantially composed of microcrystallites collectively of the formula:m.sub.2m.sup.2+ Al.sub.2-p M.sub.p.sup.3+ T.sub.r O.sub.7+r.multidot.swhere M.sup.2+ is a divalent metal, M.sup.3+ is a trivalent metal, and T is vanadium, tungsten, or molybdenum. The microcrystallites are so small as to be undetectable through conventional x-ray diffraction techniques, yet high resolution electron microscopy reveals that a substantial portion of the microcrystallites are composed of a solid solution having aluminum oxide molecularly dispersed in a divalent metal monoxide crystal structure. Another portion of the microcrystallites are constituted by a spinel phase. The collapsed composition is suitable as a sulfur oxide absorbent, having comparatively high capacity and comparatively fast absorption and desorption rates, and is also suitable as a nitrogen oxide reduction catalyst.
Type:
Grant
Filed:
June 9, 1995
Date of Patent:
January 7, 1997
Assignee:
Amoco Corporation
Inventors:
Alakananda Bhattacharyya, Michael J. Foral, William J. Reagan
Abstract: A method for reducing contaminant concentrations in a fluid stream including the steps of forming a metal-complexed material having a surface suitable for exchange with the contaminant, contacting the fluid stream with the metal-complexed material, immobilizing at least a portion of the contaminant on the surface of the metal-complexed material, and regenerating the metal-complexed material so as to remove the contaminant from the surface of the metal-complexed material. The metal-complexed material is formed by the encapsulating of a core of ferromagnetic material with an ion exchange material. The metal-complexed material is magnetically affixed to a metallic mesh retaining surface.
Type:
Grant
Filed:
March 28, 1994
Date of Patent:
August 20, 1996
Inventors:
Samuel L. Shepherd, Anthony M. Wachinski
Abstract: The gas stream which emanates from landfills is treated to produce a purified gas which is essentially a hydrocarbon such as methane which can be used as the fuel source in a fuel cell power plant, or can be used in other power plants which use natural gas as a fuel. The landfill gas passes through a system which removes essentially all of the hydrogen sulfide; water; organic sulfur and halogen compounds; and solid contaminants from the gas stream. The resultant purified gas stream can be cleanly flared; used to power an energy plant; or put to other useful purposes.
Type:
Grant
Filed:
June 14, 1994
Date of Patent:
September 19, 1995
Assignee:
International Fuel Cells
Inventors:
Ronald J. Spiegel, Richard A. Sederquist, John C. Trocciola, Herbert C. Healy, Roger R. Lesieur, Gregory J. Sandelli
Abstract: Improved processes for treating gas streams containing hydrogen sulfide, carbon dioxide, water vapor and methane, particularly natural gas streams. The processes rely on the availability of two membrane types, one of which has a hydrogen sulfide/methane selectivity of at least about 40 when measured with multicomponent gas mixtures at high pressure. Based on the different permeation properties of the two membrane types, optimized separation processes can be designed. The membrane separation is combined with non-membrane treatment of the residue and/or permeate streams.
Type:
Grant
Filed:
October 25, 1993
Date of Patent:
April 18, 1995
Assignee:
Membrane Technology and Research, Inc.
Inventors:
Kaaeid A. Lokhandwala, Richard W. Baker
Abstract: A process produces fibers from polymers which give off troublesome gases and/or vapors during spinning, comprising the steps of:a) extruding the molten polymer through a spinneret into a closed spinning shaft,b) quenching the resulting filaments in the spinning shaft with a gas,c) taking off the resulting filaments from the spinning shaft,d) conducting the quench gas away from the spinning shaft and introducing it into a gas purification system ande) purifying the used quench gas by contact with an adsorbent for said troublesome gases and/or vapors.It is possible by the present invention to keep hazardous gases occurring during the spinning of polymers away from the surroundings and to dispose of them. Suitable polymers are in particular polyphenylene sulfides.
Type:
Grant
Filed:
July 26, 1993
Date of Patent:
December 6, 1994
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Herbert Wellenhofer, Gerhard Leumer, Andreas Fischer, Diethelm Rabe, Hans-Jurgen Profe
Abstract: A sulfur absorbent composition having desirable physical properties and comprising zinc oxide and alumina having been treated with a phosphating agent is disclosed. At least a portion of the alumina component of the absorbent composition undergoes a phosphating treatment. The resulting composition is suitable for use in an H.sub.2 S absorption process.
Abstract: A continuous process for the removal of hydrogen sulfide from a gas stream using a membrane comprising a metal oxide deposited on a porous support is disclosed.
Abstract: A novel composition comprising zinc oxide and at least one metal phosphate that can be effectively used to remove sulfur compounds from a fluid stream by contacting said fluid stream under suitable absorption conditions with this novel composition. Also, a novel method is described for making a composition comprising mixing with zinc oxide at least one metal phosphate followed by the addition of a dilute acid to form a paste or paste like material having a desired consistency for agglomeration.
Type:
Grant
Filed:
December 1, 1992
Date of Patent:
December 7, 1993
Assignee:
Phillips Petroleum Company
Inventors:
Gary A. Delzer, Ted H. Cymbaluk, Dennis R. Kidd, Gerhard P. Nowack
Abstract: Natural gas containing hydrogen sulfide is treated at well-head pressures by contact with a crystalline substituted or unsubstituted stannosilicate for removal of hydrogen sulfide.
Type:
Grant
Filed:
April 30, 1992
Date of Patent:
November 23, 1993
Assignee:
Exxon Research and Engineering Company
Inventors:
Edward W. Corcoran, Jr., David E. W. Vaughan, Paul E. Eberly, Jr., Killian D. Efird
Abstract: Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 .mu.m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO.sub.3 ; and then indurating it at 800.degree. to 900.degree. C. for a time sufficient to produce attrition-resistant granules.
Type:
Grant
Filed:
March 26, 1992
Date of Patent:
October 19, 1993
Assignee:
Research Triangle Institute
Inventors:
Raghubir P. Gupta, Santosh K. Gangwal, Suresh C. Jain
Abstract: The composition of this invention is a silicated zinc oxide that comprises a co-gelled mixture comprising zinc oxide and silica. This co-gelled mixture is used as a sorbent for removing sulfur compounds from sulfur containing fluids by contacting such fluids with the sorbent. The composition can be prepared by a silicating process wherein the composition is manufactured by silicating zinc oxide to form a co-gelled mixture.