Forming Silica Gel Patents (Class 502/233)
  • Patent number: 5695730
    Abstract: The present invention provides silicic acid hydrate having a large pore volume and tiny particle diameters, and a process for preparing it. There is disclosed silicic acid hydrate obtained by neutralizing an aqueous solution of sodium silicate with a mineral acid, which has particle properties represented by an oil absorption of 250 to 350 ml/100 g, a total pore volume of 4.0 to 6.0 cc/g, an average pore radius of 200 to 400 .ANG., and an average pore diameter of 3.0 to 15 .mu.m by the laser method, or 2.0 to 4.0 .mu.m by the coulter method, or 0.5 to 3.5 .mu.m by the centrifugal precipitation method.
    Type: Grant
    Filed: September 20, 1995
    Date of Patent: December 9, 1997
    Assignee: Nippon Paper Industries Co., Ltd.
    Inventors: Kuniaki Maejima, Shigeki Yamagata, Tomohiro Banda, Masaru Kishida, Keiji Monbetsu, Tsutomu Naito
  • Patent number: 5688482
    Abstract: A temperature-activated polysilicic acid is prepared by heating an acidified aqueous alkali metal silicate. The temperature-activated polysilicic acid is used in the production of paper for improvement of retention and water removal.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: November 18, 1997
    Assignee: J. M. Huber Corporation
    Inventor: Sakari Saastamoinen
  • Patent number: 5661097
    Abstract: A supported catalyst component for an olefin polymerization catalyst comprising a solid particulate support, a magnesium halide, and optionally a Group 4 or 5 transition metal compound, a Group 2 or 13 organometal compound, and an electron donor, wherein a majority of particles of the solid particulate support is in the form of an agglomerate of subparticles. A process for preparing this supported catalyst component. A catalyst composition comprising this catalyst component and a cocatalyst. An olefin polymerization process using such a catalyst composition.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: August 26, 1997
    Assignee: The Dow Chemical Company
    Inventors: Lee Spencer, Marc A. Springs
  • Patent number: 5647962
    Abstract: The invention relates to modified SiO.sub.2 gels (xerogels), the preparation thereof and the use thereof as thermal insulators. The xerogels are prepared by acidifying an aqueous waterglass solution, polycondensing the silicic acid produced thereby, by adding a base, to an SiO.sub.2 gel, removing the water from the resulting gel by extractive distillation with an organic solvent which forms with water an azeotrope which separates on cooling into two phases, reacting the gel with a silylating agent, and then drying at pressures and temperatures which are below the critical pressure and/or the critical temperature of the organic solvent used for removing the water.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: July 15, 1997
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Rolf-Michael Jansen, Andreas Zimmermann
  • Patent number: 5576262
    Abstract: A method of making chromium containing oxide gel-based catalyst wherein an oxide hydrogel is convened to a xerogel by azeotropic distillation of a mixture of said hydrogel and an organic solvent, the improvement comprising impregnating the gel with a chromium compound during azeotropic distillation by incorporating said chromium compound into said mixture before azeotropic distillation and wherein the organic solvent used is selected from the group consisting of ethoxy ethyl acetate, tert-butyoxy propanol, methoxy propyl acetate, n-butoxy propanol, ethoxy ethyl propionate and mixtures thereof.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: November 19, 1996
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Dean A. Denton
  • Patent number: 5571494
    Abstract: A temperature-activated polysilicic acid is prepared by heating an acidified aqueous alkali metal silicate. The temperature-activated polysilicic acid is used in the production of paper for improvement of retention and water removal.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: November 5, 1996
    Assignee: J. M. Huber Corporation
    Inventor: Sakari Saastamoinen
  • Patent number: 5558849
    Abstract: A process for making inorganic gels by reaction of tetraalkoxy orthosilicates, tetraalkoxy titanates and tetraalkoxy zirconates with strong carboxylic acids. Water need not be present initially as a reactant. Optically clear, very small pore size, narrow pore size distribution, and high specific area inorganic gels useful for abrasion-resistant coatings, optical applications, catalyst or enzyme support, gas separation, or chromatography packing are thus produced.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: September 24, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Kenneth G. Sharp
  • Patent number: 5510555
    Abstract: A catalyst, which is active in the oligomerization of olefins is an X-ray-amorphous silica-alumina-nickel oxide gel having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of from 30/1 to 500/1, and NiO/SiO.sub.2 molar ratio of from 0.001/1 to 0.01/1, a superficial area of from 500 m.sup.2 /g to 1.000 m.sup.2 /g, and a porosity of from 0.3 ml/g to 0.6 ml/g, the means pore diameter being 1 nm (10 Angstrom), and devoid of pores having a diameter over 3 nm (30 Angstrom). The catalyst selectively dimerizes isobutene into alpha- and beta-isobutene and oligomerizes propylene into its relative dimers and trimers. A process is described for preparing the silica-alumina-nickel oxide gel.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: April 23, 1996
    Assignee: Eniricerche, S.p.A.
    Inventors: Maurizio Brunelli, Walter Castelvetro, Giuseppe Bellussi, Stefano Peratello
  • Patent number: 5486598
    Abstract: A method for synthesizing polypeptides from amino acids and/or peptides utilizing a novel reaction medium containing a hydrated silica entity containing silanol groups which function as an inorganic enzyme.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: January 23, 1996
    Assignee: University of Florida
    Inventors: Jon K. West, Larry L. Hench
  • Patent number: 5441718
    Abstract: A process for making inorganic gels by reaction of tetraalkoxy orthosilicates, tetraalkoxy titanates and tetraalkoxy zirconates with strong carboxylic acids. Water need not be present initially as a reactant. Optically clear, very small pore size, narrow pore size distribution, and high specific area inorganic gels useful for abrasion-resistant coatings, optical applications, catalyst or enzyme support, gas separation, or chromatography packing are thus produced.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: August 15, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Kenneth G. Sharp
  • Patent number: 5380510
    Abstract: This invention provides a method for manufacturing silica gels in a form of scales or needles having a pore volume and a specific surface area being relatively large and being controlled. Silicic acid sol is frozen, crystallized and deposited in gaps among crystal faces of crystals of solvent of the sol, thus obtaining the frozen silica hydrogels in the form of scales or needles. After unfreezing the frozen silica hydrogels, a hydrothermal polymerization is carried out. Subsequently, the silica hydrogels are dried, thus obtaining the silica gels in the form of scales or needles. Furthermore in the invention, by controlling the gelation time period of silica sol, the silica gels with their configuration controlled can result from even inexpensive silica sol. The invention has the advantage that a freeze-drying step is not required: just through freezing, unfreezing, washing and hydrothermal polymerization steps, the physical properties of the silica gels can be controlled.
    Type: Grant
    Filed: December 9, 1993
    Date of Patent: January 10, 1995
    Assignee: Fuji-Davison Chemical Ltd.
    Inventors: Takashi Matsui, Nobuki Watanabe, Masayuki Arimura, Eiji Kanemaru, Yuzo Horinouchi, Mutsuhiro Ito
  • Patent number: 5368833
    Abstract: Silica sols having a high content of microgel and aluminum modified particles with high specific surface area. The sols can be prepared by a process comprising acidification of a water glass solution, alkalization at a certain dry substance content, particle growth and aluminum modification. The sols are particularly suitable for use as additives, in combination with cationic polymers, in papermaking.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: November 29, 1994
    Assignee: Eka Nobel AB
    Inventors: Hans E. Johansson, Bo V. Larsson
  • Patent number: 5360572
    Abstract: A porous light-weight getter which collects particulate and molecular contaminates that is believed a significant improvement over the prior art is provided in which a metal mesh matrix is coated with a low-density porous aerogel. In the prior art bare metal mesh matrices have been employed as getters, which are subject to ablation from high-velocity contaminant particles. In the composite getter of the present invention, the low-density aerogel coating protects the enclosed metal matrix from ablation and also can attract and hold the incoming high-velocity particle. On its part, the metal mesh provides reinforcing support to the aerogel covering and also good thermal conductivity therein so that such covering can be cooled to the low temperatures that attract such contaminants. The invention further provides method for manufacture of the composite getters of the invention.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: November 1, 1994
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Steven P. Hotaling, Deidra A. Dykeman
  • Patent number: 5348923
    Abstract: Silica-based substrate surface-modified by grafting covalent links of organic polysubstituted guanidinium groups, and preferably polyakylguanidinium groups. These substrates can be obtained by reacting silica with a polyalkylguanidinium anion, the silanol residual groups of silica being optionally treated with hexamethyldisilazane to stabilize the substrates. These substrates can be used as chlorination and esterification catalysts.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: September 20, 1994
    Assignee: Societe Nationale des Poudres et Explosifs - S.N.P.E.
    Inventors: Patricia Gauthier, Philippe Gros, Pierre Le Perchec, Jean-Pierre Senet
  • Patent number: 5346875
    Abstract: This invention is to a method of manufacturing fluid catalytic cracking catalyst. In particular, the invention is to a method of manufacturing a catalytic cracking catalyst which incorporates a step of matching the isoelectric point of each component of the catalyst framework structure to the pH of an inorganic oxide sol used to form the matrix component of the catalyst. The resulting catalyst product has a controlled pore size and is extremely durable.
    Type: Grant
    Filed: July 21, 1993
    Date of Patent: September 13, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: William A. Wachter, Stuart L. Soled
  • Patent number: 5308533
    Abstract: A porous light-weight getter which collects particulate and molecular contaminates that is believed a significant improvement over the prior art is provided in which a metal mesh matrix is coated with a low-density porous aerogel. In the prior art bare metal mesh matrices have been employed as getters, which are subject to ablation from high-velocity contaminant particles. In the composite getter of the present invention, the low-density aerogel coating protects the enclosed metal matrix from ablation and also can attract and hold the incoming high-velocity particle. On its part, the metal mesh provides reinforcing support to the aerogel covering and also good thermal conductivity therein so that such covering can be cooled to the low temperatures that attract such contaminants. The invention further provides method for manufacture of the composite getters of the invention.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: May 3, 1994
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Steven P. Hotaling, Deidra A. Dykeman
  • Patent number: 5275796
    Abstract: A two-step method is described for making transparent aerogels which have a density of less than 0.003 g/cm.sup.3 to those with a density of more than 0.8 g/cm.sup.3, by a sol/gel process and supercritical extraction. Condensed metal oxide intermediate made with purified reagents can be diluted to produce stable aerogels with a density of less than 0.02 g/cm.sup.3. High temperature, direct supercritical extraction of the liquid phase of the gel produces hydrophobic aerogels which are stable at atmospheric moisture conditions. Monolithic, homogeneous silica aerogels with a density of less than 0.02 to higher than 0.8 g/cm.sup.3, with high thermal insulation capacity, improved mechanical strength and good optical transparency, are described.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: January 4, 1994
    Assignee: Regents of the University of California
    Inventors: Thomas M. Tillotson, John F. Poco, Lawrence W. Hrubesh, Ian M. Thomas
  • Patent number: 5270027
    Abstract: The invention relates to high-porosity silica xerogels and a process for their preparation consisting of subjecting silica alcogels to thermal treatment in the presence of organic compounds containing amino and hydroxyl groups.The xerogels are characterised by a total pore volume .gtoreq.2 cc/g and a mean pore diameter .gtoreq.100 .ANG..
    Type: Grant
    Filed: October 14, 1992
    Date of Patent: December 14, 1993
    Assignee: Istututo Guido Donegani S.p.A.
    Inventors: Luigi Balducci, Franco Montino, Guido Cogliati
  • Patent number: 5231066
    Abstract: A bimodal silica gel particle, its method of preparation and its use as a catalyst support in the polymerization of olefins is disclosed. The bimodal silica gel particle exhibits a bimodal pore radius distribution, wherein the silica gel particle has a first average pore radius and a second average pore radius differing by at least about 20 .ANG.. The bimodal silica gel particle is useful as a support for a transition metal-based catalyst to provide a polyolefin having a broad or bimodal molecular weight distribution.
    Type: Grant
    Filed: September 11, 1991
    Date of Patent: July 27, 1993
    Assignee: Quantum Chemical Corporation
    Inventors: Louis J. Rekers, Roger D. Laib
  • Patent number: 5229096
    Abstract: The subject invention is a new type of silica gel and process for producing the same. The silica gel is the product of gelling alkali metal silicate with excess acid in aqueous medium containing a minute amount a polymerization modifier. The modifier and salts from the resulting gel are then leached with water before substantial drying effects have ensued. Spray-dried gel particles do not require the additional steps of aging or ammonia treating to achieve the desired result of high surface area and high pore volume. The gel can be produced to have various useful and unusual characteristics including the combination of high surface area, high pore volume, and a large average pore diameter.
    Type: Grant
    Filed: March 12, 1992
    Date of Patent: July 20, 1993
    Assignee: SCM Chemicals, Inc.
    Inventor: Howard J. Cohen
  • Patent number: 5227239
    Abstract: A method is described for making hollow aerogel microspheres of 800-1200 .mu. diameter and 100-300 .mu. wall thickness by forming hollow alcogel microspheres during the sol/gel process in a catalytic atmosphere and capturing them on a foam surface containing catalyst. Supercritical drying of the formed hollow alcogel microspheres yields hollow aerogel microspheres which are suitable for ICF targets.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: July 13, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Ravindra S. Upadhye, Sten A. Henning
  • Patent number: 5135901
    Abstract: A catalyst used in a process for producing a .beta.-hydroxyester product or a .beta.-hydroxyaldehyde product from ethylene oxide, carbon monoxide, and, optionally, hydrogen, is disclosed. This process uses, as a catalyst, a catalyst comprising rhodium, ruthenium, and a Group Va promoter.
    Type: Grant
    Filed: June 7, 1991
    Date of Patent: August 4, 1992
    Assignee: Eastman Chemical Company
    Inventor: William A. Beavers
  • Patent number: 4975405
    Abstract: There is provided by this invention a finely divided hydrated silica gel which has a specific surface area of 530 -720 m.sup.2 /g, preferably 550-650 m.sup.2 /g, a pore volume of 0.9-1.5 ml/g, preferably 1.0-1.4 ml/g, a mean pore diameter of 50-120 .ANG., preferably 60-100 .ANG., a water content of 7-25% by weight, preferably 8-13% by weight (wet weight basis), and moreover the pH of which as a 5% aqueous suspension is 6.0-8.0, thereby producing a silica gel suitable for stabilization treatment of beer, and for reduction of the colloidal components in beer.
    Type: Grant
    Filed: September 12, 1986
    Date of Patent: December 4, 1990
    Assignees: Fuji-Davison Chemical Ltd., Kirin Brewery Company Limited
    Inventors: Katsutoshi Okamura, Yasuo Esaki, Koichi Matsuzawa, Katsuhiko Asano
  • Patent number: 4894357
    Abstract: A process for adjusting at least one of the structural and surface characteristics of an oxide material, e.g. SiO.sub.2 or Al.sub.2 O.sub.3, by dehydration of a water-containing oxide gel under supercritical conditions by extracting the water with an extraction agent such as CO.sub.2 at a pressure above the critical pressure of the extraction agent.
    Type: Grant
    Filed: October 31, 1985
    Date of Patent: January 16, 1990
    Assignee: Kali-Chemie Aktiengesellschaft
    Inventors: Bernd Hupe, Robert Walter
  • Patent number: 4849378
    Abstract: A method of fabricating an ultraporous SiO.sub.2 containing gel monoliths having a predetermined mean pore size with narrow distribution of the size of the pores around the mean. A SiO.sub.2 containing sol is prepared while simultaneously controlling and preselecting the temperature, time and nature of aging solution, and drying the resultant gel to obtain an ultraporous SiO.sub.2 containing monolith having a predetermined mean pore size from about 10 .ANG. to about 400 .ANG. with narrow distribution of the size of pores around the mean and the resultant article.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: July 18, 1989
    Assignee: University of Florida
    Inventors: Larry L. Hench, Gerard F. Orcel
  • Patent number: 4717708
    Abstract: The invention is directed to inorganic oxide aerogels and the method of preparing such inorganic oxide aerogels which are characterized by high surface areas and high pore volume. The preparation comprises dissolving the inorganic alkoxide or metal salt in a solvent optionally containing a catalytic amount of an acid or base and hydrolyzing to form a gelled or colloidal material which is further treated with a fluid at or above its critical temperature and pressure to extract the solvent which is then dried to remove surface water.
    Type: Grant
    Filed: December 27, 1983
    Date of Patent: January 5, 1988
    Assignee: Stauffer Chemical Company
    Inventors: Chung-Ping Cheng, Paul A. Iacobucci
  • Patent number: 4619908
    Abstract: The invention is directed to inorganic oxide-containing aerogels and the method of preparing such oxide-containing aerogels which are characterized by high surface areas and high pore volume. The preparation comprises dissolving the inorganic alkoxide or metal salt in a solvent optionally containing a catalytic amount of an acid or base and hydrolyzing the metal compound which is then further treated with a fluid at or above its critical temperature and pressure to extract the solvent.
    Type: Grant
    Filed: December 24, 1984
    Date of Patent: October 28, 1986
    Assignee: Stauffer Chemical Company
    Inventors: Chung-Ping Cheng, Paul A. Iacobucci, Edward N. Walsh
  • Patent number: 4565794
    Abstract: Sericitic clays can be treated so as to produce silica gel and an adsorbent, absorbent product capable of being utilized in many different applications. In treating such clays to produce such products, finely ground clay particles are digested with an alkali so as to produce an alkali silicate solution which is separated from the remaining inorganic material. The latter is digested with an acid so as to remove alumina values. The particles remaining should then be washed and dried prior to being used as an adsorbent, absorbent material. The alkali silicate solution is preferably subjected to electrolysis to bleach contaminants within the solution and then treated with an acid so as to gel the silicate. After the gel is formed, the gel and the solution are neutralized. The gel is then separated and dried.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: January 21, 1986
    Assignee: John Stephens
    Inventor: Francis de Buda
  • Patent number: 4537866
    Abstract: A method of preparing a silica-containing composition from a lithium silicate sol is disclosed. The compositions are prepared by heating shaped particles of lithium silicate sol to a temperature of about 70.degree. C. or more in the absence of a gelling agent and thereafter subjecting the particles to a washing step to remove lithium therefrom. By means of the novel method it is possible to prepare silica-containing compositions which are suitable as catalyst and/or adsorbent supports.
    Type: Grant
    Filed: March 29, 1984
    Date of Patent: August 27, 1985
    Assignee: UOP Inc.
    Inventor: Jean-Pierre Gilson
  • Patent number: 4529504
    Abstract: A process is described for removing both high polar and neutral nitrogen compounds from petroleum processing liquid products and petroleum distillate fractions. According to the novel feature, a chlorosilylated silica gel is used as adsorbent for the nitrogen compounds. This adsorbent has been found to be superior to regular silica gel and commercial ion exchange resins for removing particularly the neutral nitrogen compounds.
    Type: Grant
    Filed: February 9, 1984
    Date of Patent: July 16, 1985
    Assignee: Canadian Patents and Development Limited-Societe Canadienne des Brevets et d'Exploitation Limitee
    Inventors: Marc-Andre Poirier, Albert E. George
  • Patent number: 4504595
    Abstract: An improved fluorinated siliceous catalyst, well adapted for the catalytic synthesis of aromatic/aliphatic nitriles from their corresponding formamides, formanilides or amides, is comprised of a plurality of silica particulates, the specific surface of which ranging from about 200 to about 300 m.sup.2 /g, having a total pore volume ranging from about 1 to about 1.5 cm.sup.3 /g, with an average pore diameter ranging from about 100 to about 200 .ANG., having an exchange pH of less than about 3, and with the fluorine content thereof bonded to the silica, expressed in F.sup.-, ranging from about 0.05 to about 2% by weight based upon the silica, and the sodium content thereof, expressed as Na.sub.2 O, being less than about 1% by weight, also based upon the silica.
    Type: Grant
    Filed: May 14, 1982
    Date of Patent: March 12, 1985
    Assignee: Rhone-Poulenc Specialites Chimiques
    Inventors: Roland Jacques, Michel Reppelin, Laurent Seigneurin
  • Patent number: 4436882
    Abstract: A silica hydrogel containing chromium is aged under conditions such that at least a portion of the aging is carried out at a pH within the range of 7 to 9. The resulting hydrogel is converted to a xerogel by treating with a volatile organic liquid. The desired pH can be obtained either by adding a basic material such as ammonia to the hydrogel prior to or during the aging process or by using a chromium component which inherently gives a higher pH and/or resists the natural tendency for the pH to decrease during aging. An example of such a chromium compound is chloropentammine chromium(III) chloride. The resulting catalyst on activation is particularly suitable for olefin polymerization under conditions where higher melt flow polymer is desired.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: March 13, 1984
    Assignee: Phillips Petroleum Company
    Inventor: Donald R. Witt
  • Patent number: 4436883
    Abstract: A silica hydrogel is contacted with a hydroxy-containing organic compound which is not completely miscible with water but which is sufficiently miscible with water so as to remove water, and thereafter the organic compound is removed by heating in an inert atmosphere prior to activation by heating in air. The heating in the inert atmosphere allows utilizing preferred organic compounds such as C.sub.5 and C.sub.6 alcohols which are desirable from a commercial standpoint because of the easy separation for recycle. In a preferred embodiment, the hydrogel is aged at a pH of 7 to 9 by means of either adding a base or by utilizing a chromium component containing bound nitrogen.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: March 13, 1984
    Assignee: Phillips Petroleum Company
    Inventor: Donald R. Witt
  • Patent number: 4414137
    Abstract: Catalytically active amorphous silicas are prepared by dehydrating a silica hydrogel or precipitate prepared from an acidified aqueous silicate solution containing an amine of pK.sub.a above 10 or a cation containing either a nitrogen or phosphorus atom bonded to four carbon atoms. The resultant amorphous silica is catalytically active for, among other chemical reactions, the isomerization of ortho-xylene and the cracking of hydrocarbons.
    Type: Grant
    Filed: March 9, 1982
    Date of Patent: November 8, 1983
    Assignee: Union Oil Company of California
    Inventors: Dean A. Young, Jeffery W. Koepke