Patents by Inventor Robert P. Kreh

Robert P. Kreh 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: 5344590
    Abstract: A method for inhibiting corrosion of metals in contact with an aqueous solution comprising adding to the system a corrosion inhibiting amount of one or more polytartaric acid compounds having the generalized formula: ##STR1## wherein each R is independently selected from the group consisting of H and C.sub.1 to C.sub.4 alkyl, n is less than 4 and the average molecular weight of the mixture corresponds to an average n in the range 1.2 to 3.
    Type: Grant
    Filed: January 6, 1993
    Date of Patent: September 6, 1994
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Charles G. Carter, Lai-Duien G. Fan, Joseph C. Fan, Robert P. Kreh, Vladimir Jovancicevic
  • Patent number: 5223146
    Abstract: A method for treating an aqueous system which contains solid particles of iron (III) oxide is disclosed which comprises adding to the system catechol, hydroquinone, their water soluble salts, and mixtures thereof in an amount effective to disperse or suspend iron (III) oxide particles. The aqueous system should have a pH greater than 7 and have low to moderate hardness.
    Type: Grant
    Filed: October 9, 1991
    Date of Patent: June 29, 1993
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Robert P. Kreh
  • Patent number: 5183590
    Abstract: A composition and method for inhibiting corrosion of ferrous metals in contact with an aqueous solution comprising adding to the system from 0.1 to 500 ppm of an aminohydroxysuccinic acid compound selected from group consisting of compounds of the generalized formulas: ##STR1## wherein R is H or C.sub.1 to C.sub.6 alkyl, optionally substituted with --OH, --CO.sub.2 H, --SO.sub.3 H or phenyl, C.sub.4 C.sub.7 cycloalkyl, or phenyl which is optionally substituted with --OH, or --CO.sub.2 H, and R' is H, C.sub.1 to C.sub.6 alkyl, optionally substituted with --OH or CO.sub.2 H; and ##STR2## wherein R' is as above, and Z is selected from the group consisting of i) --(CH.sub.2).sub.n -- wherein n is an integer from 2 to 10, ii) --(CH.sub.2).sub.2 --X--(CH.sub.2).sub.2 -- wherein X is --O--, --S--, --NR"--; wherein R" is selected from the group consisting of H, C.sub.1 to C.sub.6 alkyl, hydroxyalkyl, carboxyallkyl, acyl, --C(O)OR"' wherein R"' is C.sub.1 C.sub.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: February 2, 1993
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Charles G. Carter, Vladimir Jovancicevic, Judith A. Hartman, Robert P. Kreh
  • Patent number: 5183573
    Abstract: A process for preventing or removing calcium and rust scale deposits from surfaces which are in contact with aqueous systems comprising adding to the aqueous system 3,5-bis(di-N,N-(carboxymethyl)aminomethyl)-4-hydroxybenzenesulfonic acid in an amount effective to remove the scale and rust deposits.
    Type: Grant
    Filed: July 22, 1991
    Date of Patent: February 2, 1993
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Robert P. Kreh, Wayne L. Henry
  • Patent number: 5183574
    Abstract: A method of comprising iron in an aqueous system comprising adding to the system a copolymer of styrene sulfonic acid and methacrylic acid or its water soluble salt in an amount effective to disperse the iron contained therein.
    Type: Grant
    Filed: November 18, 1991
    Date of Patent: February 2, 1993
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Chih M. Hwa, John A. Kelly, Wun T. Tai, Lai-Duien G. Fan, Robert P. Kreh, Brian Greaves
  • Patent number: 5171477
    Abstract: The present invention is directed to a method of inhibiting corrosion in aqueous systems which employ amino acid chelants in concentrations which are corrosive to the metal surfaces in contact with the aqueous system. The method comprises adding to the system a corrosion inhibiting amount of 1-hydroxyethane-1,1-diphosphonic acid (HEDPA). The corrosion inhibiting amount is generally in the range of from 0.5% to 10% on the basis of the concentration of amino acid chelant in the system.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: December 15, 1992
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Robert P. Kreh
  • Patent number: 5139702
    Abstract: A composition useful for treating aqueous systems comprising a naphthylamine polycarboxylic acid having the formula: ##STR1## wherein X is CO.sub.2 H or SO.sub.3 H, Y is H, C.sub.1 to C.sub.6 alkyl, CO.sub.2 H or SO.sub.3 H, R is H, C.sub.1 to C.sub.6 alkyl, CO.sub.2 R' or COR', R' is C.sub.1 to C.sub.6 alkyl, n is an integer from 1 to 20, and water soluble salts thereof.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: August 18, 1992
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Charles G. Carter, Robert P. Kreh, Lai-Duien G. Fan
  • Patent number: 5130052
    Abstract: A method of inhibiting corrosion of a metal surface in an aqueous system having a pH of at least 6, comprising maintaining in the aqueous system, in an amount effective to inhibit corrosion, a water-soluble, organic-rare earth metal chelate which is derived from a rare earth metal having an atomic number from 57 to 71 and an organic chelant. The organic chelant provides not only water solubility but surprisingly enhanced corrosion inhibiting activity. The water-soluble, organic-rare earth chelates may be advantageously combined with other corrosion inhibitors such as zinc chelates, organophosphonates, phosphates, chromates, molybdates, and the like.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: July 14, 1992
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Robert P. Kreh, Vincent R. Kuhn, John Richardson, Robert M. Spotnitz, Charles G. Carter, Vladimir Jovancicevic
  • Patent number: 5102467
    Abstract: A hydraulic cement admixture capable of enhancing the latter stage set strength of the cured composition comprising certain mono- and disubstituted (dialkanolaminomethyl) phenols.
    Type: Grant
    Filed: July 19, 1991
    Date of Patent: April 7, 1992
    Assignee: W.R. Grace & Co.-Conn.
    Inventors: Ellis M. Gartner, Robert P. Kreh
  • Patent number: 5073339
    Abstract: A method of inhibiting corrosion of metal surfaces in contact with aqueous solutions and of inhibiting scale formation thereon is provided by introducing and maintaining in the solution certain polyaminopolyphosphonohydroxybenzene sulfonic acid compounds or their alkali or alkaline earth metal salts.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: December 17, 1991
    Assignee: W. R. Grace & Co. - Conn
    Inventor: Robert P. Kreh
  • Patent number: 5043099
    Abstract: New polyamino-polyphosphonic-hydroxybenzenesulfonic acid compounds as the free acid or their alkali or alkaline earth metal salt. Specifically, the compounds are the mono- and di-(1,1-diphosphono-1-alkylaminomethyl)-4-hydroxybenzenesulfonic acid. These compounds are useful as corrosion inhibiting agents for metal/water applications.
    Type: Grant
    Filed: July 13, 1990
    Date of Patent: August 27, 1991
    Inventors: Robert P. Kreh, Charles G. Carter
  • Patent number: 5022926
    Abstract: A method of removing iron contaminants in an aqueous system by introducing and maintaining within the system at least one ortho dihydroxyaromatic compound having at least one electron withdrawing group pendant from the aromatic ring and, further, a method of inhibiting calcium scale formation in the presence of iron contaminants by utilizing at least one dehydroxyaromatic compound in combination with calcium scale inhibitors.
    Type: Grant
    Filed: May 18, 1989
    Date of Patent: June 11, 1991
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Robert P. Kreh, Joseph T. Lundquist, Wayne L. Henry, John A. Kelly, Vincent R. Kuhn
  • Patent number: 4935205
    Abstract: A method of inhibiting corrosion of iron or iron-based alloys which are in contact with an aqueous system by introducing and maintaining within the system at least one ortho dihydroxyaromatic compound having at least one electron withdrawing group pendant from the aromatic ring.
    Type: Grant
    Filed: June 10, 1988
    Date of Patent: June 19, 1990
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Robert P. Kreh, Joseph T. Lundquist, Wayne L. Henry
  • Patent number: 4794172
    Abstract: A solid product of the formula Ce(CH.sub.3 SO.sub.3).sub.2 0.2H.sub.2 O, Ce(CH.sub.3 SO.sub.3).sub.2 (OH).sub.2.H.sub.2 O or other hydrates is disclosed and used as a highly effective oxidant to produce carbonyl containing products from aromatic and alkyl aromatic compounds.
    Type: Grant
    Filed: October 10, 1986
    Date of Patent: December 27, 1988
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Robert P. Kreh
  • Patent number: 4701245
    Abstract: A process for oxidizing aromatic and alkyl substituted aromatic compounds to quinonoid compounds by contacting an aromatic and alkyl aromatic compound with an acidic, aqueous solution of ceric oxidant in the presence of a catalytic amount of chromium cations. The present process provides a means of forming the desired quinonoid product in good yields and high selectivity.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: October 20, 1987
    Assignee: W. R. Grace & Co.
    Inventor: Robert P. Kreh
  • Patent number: 4692227
    Abstract: Aqueous acidic solutions of certain thallium(III) organosulfonate having at least 0.1 molar thallium ion concentration are contacted with an organic compound to form a related oxidized organic compound. The oxidized compound is separated and recovered from the solution and the resultant thallium(I) rich solution is electrochemically treated to regenerate thallium(III) which, in turn, can be reused in a cyclical process.The present invention provides a highly effective means of oxidizing organic substrates.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: September 8, 1987
    Assignee: W. R. Grace & Co.
    Inventors: Robert M. Spotnitz, Robert P. Kreh
  • Patent number: 4670108
    Abstract: A process for oxidizing aromatic and alkyl substituted aromatic compounds to carbonyl containing compounds by contacting an aromatic or alkyl aromatic compound with ceric methanesulfonate in an aqueous, weakly acidic solution containing an organic cosolvent which has at least 2 percent solubility in water under reaction conditions and is substantially inert with respect to the acidic, oxidizing conditions.
    Type: Grant
    Filed: October 10, 1986
    Date of Patent: June 2, 1987
    Assignee: W. R. Grace & Co.
    Inventors: Robert P. Kreh, Robert M. Spotnitz
  • Patent number: 4647349
    Abstract: A process for oxidizing aromatic and alkyl substituted aromatic compounds to carbonyl containing compounds by contacting an aromatic and alkyl aromatic compound with an aqueous solution of ceric trifluoromethanesulfonate having from at least 0.75 to 7 molar concentration of free acid of trifluoromethanesulfonic acid and at least 0.2 molar cerium ion concentration. The present process provides a highly effective means of forming the desired carbonyl containing product in good yields and high selectivity.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: March 3, 1987
    Assignee: W. R. Grace & Co.
    Inventors: Robert P. Kreh, Robert M. Spotnitz
  • Patent number: 4639298
    Abstract: A process for oxidizing aromatic and alkyl substituted aromatic compounds to carbonyl containing compounds by contacting an aromatic and alkyl aromatic compound with an aqueous solution of ceric methanesulfonate having from at least 1.5 to 9 molar concentration of free acid of methanesulfonic acid and at least 0.2 molar cerium ion concentration. The present process provides a highly effective means of forming the desired carbonyl containing product in good yields and high selectivity.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: January 27, 1987
    Assignee: W. R. Grace & Co.
    Inventors: Robert P. Kreh, Robert M. Spotnitz