Patents by Inventor Henry A. Pfeffer

Henry A. Pfeffer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6268191
    Abstract: Enzymes are immobilized for use in non-aqueous enzymatic reactions by dehydrating hydrocolloid gel beads having an average particle size of 5 to 150 microns and a network structure capable of swelling in aqueous media, immersing or suspending the dehyrated gel beads in an aqueous solution of enzyme where the beads swell and imbibe the enzyme solution, optionally dehydrating the resultant enzyme-containing gel beads and recovering the gel beads containing the enzyme. In a specific method, the hydrocolloid is carrageenan such a kappa carragennan, the enzyme is subtilisin Carlsberg, the aqueous enzyme solution contains 0.05% to 40 wt % enzyme and the amount of enzyme imbibed is 0.05 to 0.5 grams of enzyme per gram of dehydrated gel beads.
    Type: Grant
    Filed: September 14, 1999
    Date of Patent: July 31, 2001
    Inventors: Robert K. Prud'homme, Catherine-Ann Cukras, Henry A. Pfeffer
  • Patent number: 5662840
    Abstract: A process for making gel bead having a mean diameter of less than 50 microns by adiabatically atomizing a hydrocolloid sol to droplet of less than 50 microns under conditions that lower the temperature of the hydrocolloid below its gel temperature.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: September 2, 1997
    Assignee: FMC Corporation
    Inventors: William R. Thomas, Henry A. Pfeffer, Basil A. Guiliano, Christopher J. Sewall, Stephen Tomko
  • Patent number: 5364605
    Abstract: Process for recovering cyanide values from a mill tailings stream remaining after gold and silver have been leached from an ore, by treating the tailings stream containing both ore insolubles and remaining cyanide leachant, without a preliminary filtration, to acidification with an acid to a pH of at least 4, stripping the cyanide values therefrom with a stripping gas in a stripping column such as a baffle plate column wherein the average residence time of the column is sufficiently low that the pH of the stream does not rise above about 4 and the ore insolubles do not plug the column, introducing the stripping gas and stripped cyanide values into an absorbing column containing an alkaline liquor to absorb the cyanide values, recovering the absorbed cyanide values, and removing a stripped tailings stream reduced in cyanide values.
    Type: Grant
    Filed: June 5, 1991
    Date of Patent: November 15, 1994
    Assignee: FMC Corporation
    Inventors: Henry A. Pfeffer, Gary E. Wolfe
  • Patent number: 5045296
    Abstract: A process is provided to react anhydrous carbonate with a particle size between 300 and 74 micrometers and hydrogen peroxide containing a hydroxyalkylidene diphosphonic acid to produce sodium carbonate perhydrate containing 13% to 141/2% active oxygen. The process differs from the prior art in that reaction mixture is substantially dry at all times. The product is stable even without added stabilizers.
    Type: Grant
    Filed: January 25, 1991
    Date of Patent: September 3, 1991
    Assignee: FMC Corporation
    Inventors: Henry A. Pfeffer, Charles Adams, Jr.
  • Patent number: 4970058
    Abstract: A novel composition of matter is claimed comprising particles which appear to comprise sodium carbonate, sodium percarbonate (also called sodium carbonate peroxide or sodium carbonate perhydrate), and a stabilizer for the compound, preferably a diphosphonic acid, the sodium carbonate being present in sufficient quantity to form sodium carbonate monohydrate by reacting with the available water in the composition.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: November 13, 1990
    Assignee: FMC Corporation
    Inventors: William A. Hills, Henry A. Pfeffer
  • Patent number: 4966762
    Abstract: A novel process is claimed for manufacturing a composition of matter comprising particles which appear to comprise sodium carbonate, sodium carbonate peroxide and a stabilizer such as, a disphosphonic acid, the anhydrous sodium carbonate being present in sufficient quantity to form sodium carbonate monohydrate by reacting with all of the water formed on decomposition of the sodium percarbonate.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: October 30, 1990
    Assignee: FMC Corporation
    Inventors: Henry A. Pfeffer, William A. Hills
  • Patent number: 4781899
    Abstract: Crystal solids made via the continuous crystallization of a crude, concentrated aqueous feed solution are recovered as a crystalline solid product that is relatively free of impurities present in the crystallizer liquor. A portion of the withdrawn crystallizer slurry is concentrated in a first hydroclone, diluted with crystallizer feed solution, concentrated in a second hydroclone, and centrifuged and dried to recover the crystalline solid product.
    Type: Grant
    Filed: July 27, 1984
    Date of Patent: November 1, 1988
    Assignee: Intermountain Research & Development Corporation
    Inventors: Francis Rauh, Henry A. Pfeffer, III
  • Patent number: 4654204
    Abstract: Sodium bicarbonate is produced by introducing solid sodium carbonate, sodium sesquicarbonate, and/or Wegscheider's salt into a reversion slurry, saturated with respect to bicarbonate and containing at least 10 wt. % solids, to effect rapid and complete conversion of the feed solids to crystalline sodium bicarbonate which is recovered from the slurry. Carbon dioxide is introduced into the reversion liquor to maintain its composition at a relatively constant value, preferably in a region of the Na.sub.2 CO.sub.3 --NaHCO.sub.3 --H.sub.2 O phase diagram that minimizes the equilibrium partial pressure of CO.sub.2 vapor above such liquor.
    Type: Grant
    Filed: July 16, 1985
    Date of Patent: March 31, 1987
    Assignee: Intermountain Research & Development Corporation
    Inventors: William C. Copenhafer, Henry A. Pfeffer, III, Francis Rauh
  • Patent number: 4652054
    Abstract: A cyclic solution mining method that uses aqueous sodium hydroxide for recovering valuable alkali values, preferably as soda ash, from subterranean deposits of trona or nahcolite, even when such deposits are NaCl-contaminated. The aqueous sodium hydroxide mining solvent is generated via electrodialysis of a recirculating sodium chloride brine stream. Hydrogen chloride that is also generated in the cell's operation is neutralized with aqueous sodium carbonate, to regenerate sodium chloride brine that is recirculated to the electrodialysis cell as brine feed.
    Type: Grant
    Filed: April 16, 1985
    Date of Patent: March 24, 1987
    Assignee: Intermountain Research & Development Corporation
    Inventors: William C. Copenhafer, Henry A. Pfeffer, III
  • Patent number: 4462794
    Abstract: Method of operating a rotary calciner retrofitted from oil- or natural gas-firing to coal-firing, in which coal is burned in a coal furnace and the coal combustion gases are then heated further in a booster burner utilizing oil or natural gas, to raise the combustion gas temperature to permit processing of calcine at up to a design capacity rate.
    Type: Grant
    Filed: November 12, 1982
    Date of Patent: July 31, 1984
    Assignee: Intermountain Research & Development
    Inventors: Henry A. Pfeffer, III, Judith N. Fradkin
  • Patent number: 4294962
    Abstract: A highly-pure cyanuric acid is manufactured in a continuous process whereby urea and/or biuret are dissolved in an inert solvent and circulated at a high velocity and a temperature in the range of about 180.degree. C. to about 250.degree. C. through a loop between a heat exchanger and a forced circulation evaporative crystallizer body. Cyanuric acid crystallizes from the reaction mixture as it circulates to form a slurry. Ammonia formed during the reaction is removed at reduced pressure as the reaction mixture enters the evaporative crystallizer body. A portion of the slurry of cyanuric acid is continuously removed as it circulates through the loop and may be filtered to recover the cyanuric acid. The filtrate is returned to a feed tank and additional solvent, urea or biuret added to meet the concentration desired in the reaction mixture. The solution from the feed tank is added to the reaction mixture circulating through the loop at a rate to replace the volume of cyanuric acid slurry that is removed.
    Type: Grant
    Filed: June 25, 1980
    Date of Patent: October 13, 1981
    Assignee: FMC Corporation
    Inventors: Elizabeth A. Bagnall, Basil A. Guiliano, Henry A. Pfeffer, III
  • Patent number: 4282359
    Abstract: Cyanuric acid is mechanically separated such as by filtration, centrifugation, or centrifugal filtration from a slurry of cyanuric acid, urea, biuret, and an inert solvent in which the urea is soluble at temperatures above about 170.degree. C. to reduce the urea content of the recovered solid cyanuric acid. The biuret and solvent content of the solid cyanuric acid is also reduced.
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: August 4, 1981
    Assignee: FMC Corporation
    Inventors: Basil A. Guiliano, Henry A. Pfeffer, Andrew D. Kurtz