Abstract: A novel solid phosphoric acid catalyst composition is disclosed. The composite comprises solid phosphoric acid and a refractory oxide binder. The composite is characterized in that 25.0 volume percent or less of the total catalyst pore volume consists of pores having a diameter of 10,000 .ANG. or greater. An improvement in catalyst activity and stability is observed when such a catalyst is utilized in a hydrocarbon conversion process.
Abstract: A new class of composites results from a matrix of carbon fibers, including graphite fibers, interwoven in a network of fused metal fibers. The composites can be fabricated to have varying surface area, void volume, and pore size while maintaining high electrical conductivity. Composites are readily prepared from a preform of a dispersion of carbon fibers, metal fibers, and an organic binder such as cellulose, by heating the preform at a temperature sufficient to fuse the metal fibers and to volatilize at least 90% of the binder with a loss of less than about 25%, and usually under 10%, by weight of carbon fiber.
Type:
Grant
Filed:
May 24, 1989
Date of Patent:
January 14, 1992
Assignee:
Auburn University
Inventors:
Bruce J. Tatarchuk, Millard F. Rose, Aravamuthan Krishnagopalan, John N. Zabasajja, David A. Kohler
Abstract: This invention relates to a process for treating an exhaust gas stream from an engine, especially during cold start. The process involves a molecular sieve bed over which the cold exhaust is flowed before flowing over a catalyst bed. Pollutants such as hydrocarbons are adsorbed on the molecular sieve bed. When the molecular sieve bed reaches a temperature of about 150.degree. C., the pollutants are desorbed from the adsorbent bed and converted by the catalyst to innocuous compounds. The molecular sieves used in the process are those that selectively adsorbs pollutants, e.g., hydrocarbons versus water, and are hydrothermally stable.
Abstract: Continuous methylation of tetralin with methanol over several solid acid catalysts affords a mixture of 5-methyltetralin and 6-methyltetralin with selectivity of better than 65% at high conversions. Zeolite .beta. is a particularly effective catalyst insofar as it catalyzes the reaction at a temperature approximately 100.degree. C. lower than that required for silica-aluminas. However, the reaction temperature is quite sensitive to the concentration of methanol in the feedstock.
Abstract: This invention relates to processes for preparing ceramic articles. One process involves taking a potassium exchanged zeolite, the zeolite characterized in that it has a SiO.sub.2 /Al.sub.2 O.sub.3 ratio of 3.5 to about 7.5, and calcining it at a temperature of about 900.degree. to about 1100.degree. C. for a time sufficient to collapse the zeolite framework and provide an amorphous powder. Next, the amorphous powder is formed into a shaped article and the article is sintered at a temperature of about 1150.degree. to about 1400.degree. C. for a time of about 0.5 to about 12 hours to give a ceramic article whose principal crystalline phase is tetragonal leucite, is substantially crack free, and has less than 5% porosity.
Abstract: This invention relates to processes for preparing ceramic articles which are especially suited for electronic applications. The process involves taking a shaped article which has been formed from a magnesium exchanged zeolite powder, the zeolite selected from the group consisting of philipsite, harmotome, gismondine, zeolite B, zeolite ZK-19 and zeolite W, and sintering it at a temperature of about 1,000.degree. C. to 1,350.degree. C. for about 1 to about 6 hours. The magnesium exchanged zeolite has a SiO.sub.2 /Al.sub.2 O.sub.3 ratio of about 2.3 to about 2.8 and a sodium content less than 0.5 weight percent. The ceramic article that is formed has a substantially crystalline cordierite phase and has a density of at least 90% of its theoretical density. A preferred process involves calcining the magnesium exchanged zeolite powder at a temperature of about 600.degree.-800.degree. C. to collapse the zeolite framework and give upon sintering a cordierite ceramic article which is substantially crack free.
Abstract: This invention relates to a process for sweetening a sour hydrocarbon fraction. The process involves two steps. In one step the mercaptans in the sour hydrocarbon fraction are reacted with hydrogen in the presence of a selective hydrogenolysis catalyst to selectively hydrogenolyse the tertiary mercaptans. In another step, the mercaptans are oxidized by reacting them with an oxidizing agent in the presence of oxidation catalyst and a basic component. The selective hydrogenolysis step and the oxidation step may be carried out in any order, i.e., either hydrogenolysis first followed by oxidation or vice versa.
Type:
Grant
Filed:
February 19, 1991
Date of Patent:
November 12, 1991
Assignee:
UOP
Inventors:
Robert R. Frame, Jeffery C. Bricker, Laurence O. Stine
Abstract: A method of reducing soluble Cr(VI) levels in aqueous wastes from 200 ppm or more to less than 1 ppm, particularly to less than 0.05 ppm, preferably to less than 0.01 ppm, uses fermentative sulfate-reudcing anaerobic bacteria to reduce Cr(VI) to Cr(III) and immobilize the latter as the extememly insoluble hydroxide. The process is readily adapted to operate continuously using a bioreactor containing sludge with sulfate-reducing anaerobic bacteria and operated as a chemostat.
Type:
Grant
Filed:
March 20, 1990
Date of Patent:
November 5, 1991
Assignee:
Allied-Signal Inc.
Inventors:
F. Stephen Lupton, Louis J. DeFilippi, James R. Goodman
Abstract: Molecular sieve compositions having three-dimensional microporous framework structures of BO.sub.2, AlO.sub.2, PO.sub.2 and SiO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR:(B.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline port system; "m" represents the molar amount of "R" present per mole of (B.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2 ; and "w", "x", "y" and "z" represent the mole fraction of boron, aluminum, phosphorus and silicon, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.
Type:
Grant
Filed:
March 28, 1986
Date of Patent:
October 15, 1991
Assignee:
UOP
Inventors:
Edith M. Flanigen, Richard T. Gajek, Brent M. T. Lok, Robert L. Patton, Stephen T. Wilson
Abstract: This invention relates to a process for treating an engine exhaust gas stream. The process involves first flowing the engine exhaust stream, which is relatively cool, over an adsorbent zone which comprises an adsorbent bed, i.e., a molecular sieve bed, capable of preferentially adsorbing pollutants such as hydrocarbons. This provides a first exhaust stream which is flowed over a primary castalyst which converts the pollutants to innocuous compounds and then discharging the resultant treated exhaust stream to the atmosphere. When the adsorbent bed reaches a temperature of about 150.degree. C., the entire engine exhaust stream is completely diverted over the primary catalyst. When the inlet temperature to the primary catalyst has reached about 350.degree. C., a minor portion of the engine exhaust stream is diverted over the adsorbent bed to desorb the pollutants adsorbed on the bed and carry them over the primary catalyst where they are converted to innocuous components.
Abstract: An economical method of converting mannose to fructose uses a mannose isomerase from Pseudomonas cepacia immobilized on an alumina containing polyethyleneimine crosslinked with an excess of glutaraldehyde. The method utilizes mannose-containing aqueous solutions as the feedstock, and affords solutions in which at least 55% of the mannose has been converted to fructose. Because of the relatively higher levels of fructose than can be obtained by isomerizing glucose to fructose using glucose isomerase, substantial savings in separation of high fructose-containing products can be achieved. The process described represents the first economical mannose isomerase process.
Abstract: Although high naphthenic acid hydrocarbon feedstocks normally need to be washed with caustic prior to being sweetened in a fixed bed mercaptan-to-disulfide oxidation process to avoid bed plugging, the prewash can be eliminated if aqueous ammonia is used concurrent with and as a part of the sweetening process. Aqueous ammonia injected into a sour hydrocarbon stream prior to the sweetening zone not only eliminates bed plugging, but affords an aqueous phase from which naphthenic acids may be recovered easily and economically. The ammonia also can be recovered for reuse, affording a process with considerably enhanced economic return.
Type:
Grant
Filed:
March 19, 1990
Date of Patent:
August 13, 1991
Assignee:
UOP
Inventors:
Laurence O. Stine, Jeffery C. Bricker, Gregory J. Thompson, Thomas A. Verachtert
Abstract: Hydrogen sulfide can be conveniently removed from streams containing up to about 1,000 ppm of H.sub.2 S by reacting the latter with an olefin using a bed of an acidic solid catalyst in a non-oxidative process for the removal of hydrogen sulfide. The reaction can be effected under relatively mild conditions and is very selective for the removal of hydrogen sulfide without being attended by other unwanted reactions such as oligomerization, disproportionation, and skeletal rearrangement. Levels of hydrogen sulfide in the treated product of no more than about 5 ppm can be readily attained using a broad variety of acidic solid catalysts and unsaturated hydrocarbons, especially olefins.
Abstract: Molecular sieve compositions having three-dimensional microporous framework structures of GaO.sub.2, AlO.sub.2 and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR:(Ga.sub.x Al.sub.y P.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (Ga.sub.x Al.sub.y P.sub.z)O.sub.2 ; and "x", "y" and "z" represent the mole fractions of gallium, aluminum and phosphorus, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.
Type:
Grant
Filed:
February 19, 1986
Date of Patent:
July 16, 1991
Assignee:
UOP
Inventors:
Edith M. Flanigen, Brent M. T. Lok, Robert L. Patton, Stephen T. Wilson
Abstract: The yellow pigments which result from reaction of the Monascus pigments monascorubrin and rubropunctatin with amines followed by reduction of the ring carbonyl moiety to an hydroxyl group have excellent properties for their use as food colorants. Yellow pigments made from amino acid esters, dipeptide esters, and amines of sugar alcohols have particular promise as desirable food colorants which are effective at levels which impart no objectionable taste to foods.
Type:
Grant
Filed:
August 3, 1990
Date of Patent:
May 7, 1991
Assignee:
UOP
Inventors:
Edward J. St. Martin, Paul R. Kurek, Elaine F. Schumacher, Ronald P. Rohrbach
Abstract: The orange, water-insoluble pigments monascorubrin and rubropunctatin elaborated by Monascus species can be converted to high purity red, water-soluble pigments by reaction with stoichiometric quantities of organic materials bearing a primary amine functionality. These pigments are suitable as colorants for a broad variety of edible formulations, especially those intended for human consumption, and often serve as suitable replacements for FD&C Red No. 2 and Red No. 4.
Type:
Grant
Filed:
August 3, 1990
Date of Patent:
May 7, 1991
Assignee:
UOP
Inventors:
Edward J. St. Martin, Paul R. Kurek, Elaine F. Schumacher
Abstract: This invention relates to a process for separating a mixture of molecular species based on the molecular size (kinetic diameter) or on the degree of polarity of the molecular species using a crystalline composition having a three-dimensional microporous structure of MA.sub.2 units where A is sulfur or selenium and having the empirical formula expressed in molar ratios: xR:MA.sub.2.+-.0.2 :zH.sub.2 O where R represents at least one organic templating agent present in the intracrystalline pore system, x is the moles of R, z is the moles of water and M is germanium or tin. A composition having the empirical formula expressed in molar ratios: xR:M.sub.1-y M'.sub.y A.sub.2.+-.0.2 :zH.sub.2 O, where M' is a metal such as cobalt, zinc, manganese, iron, nickel, copper, cadmium and gallium may also be used in the process.
Type:
Grant
Filed:
April 12, 1990
Date of Patent:
May 7, 1991
Assignee:
UOP
Inventors:
Robert L. Bedard, Lawrence D. Vail, Stephen T. Wilson, Edith M. Flanigen
Abstract: Normal methods of impregnating silicalite with noble metals leads either to metal loadings under 8% at high (greater than 60%) dispersion or loading of over 8% noble metal at low dispersion. To obtain silicalite impregnated with a noble metal at more than 8 weight percent loading and with at least 60% dispersion it has been found necessary to pretreat the silicalite with a base and to impregnate the base treated silicalite with a noble metal compound in two stages separated by calcination. Platinized silicalite so prepared may be dispersed in a poly(tetrafluoroethylene) matrix and used as a fixed bed to catalyze isotopic exchange gaseous hydrogen and water vapor arising from a mass of liquid water flowing over the fixed catalyst bed.
Type:
Grant
Filed:
September 5, 1989
Date of Patent:
May 7, 1991
Assignee:
UOP
Inventors:
Mark T. Staniulis, Douglas E. Crozier, Alan P. Risch, Jenny L. Pai
Abstract: Membrane separation of monosaccharides from an aqueous solution containing higher saccharides and saccharifying enzyme is considerably improved when the separation is performed under conditions where the polarization modulus for the enzyme is between 10 and 1,000, especially when the latter is between 50 and 500. A process utilizing this constraint affords a considerable savings in enzyme residence time and enzyme usage, and permits glucose of at least 94% purity to be prepared using membranes with a molecular weight cutoff as high as 70,000 with partial saccharification of thinned starch to give glucose levels in the range of 65-90%.
Abstract: Two Bacillus species and one Pseudomonas species isolated from soil samples showed good cyclodextrin glycosyltransferase activity, even when grown in simple media. The microorganisms are not pH sensitive and grow well in media containing only starch, a nitrogen source, and minerals. All elaborate the desired enzyme within 4 hours of culturing with growth being complete within about 24 hours.
Type:
Grant
Filed:
August 5, 1988
Date of Patent:
April 16, 1991
Assignee:
UOP
Inventors:
Paul Allenza, Christy G. Clifft, Marie J. Morrell