Aqueous Acid Environment (i.e.,ph Less Than Or Equal To 4.1) Patents (Class 422/12)
  • Patent number: 6103144
    Abstract: Non-halogen substituted, nitrogen containing, aromatic compounds are disclosed which are effective copper corrosion inhibitors in aqueous systems being treated with a halogen biocide. The materials of the present invention exhibit copper corrosion inhibition comparable to tolyltriazole in the absence of halogen, copper corrosion rates of less than about 2.5 mills per year in aqueous systems where halogen is present; and do not exhibit a detrimental effect on halogen demand in an aqueous system being treated.
    Type: Grant
    Filed: April 12, 1999
    Date of Patent: August 15, 2000
    Assignee: BetzDearborn Inc.
    Inventor: Longchun Cheng
  • Patent number: 6096348
    Abstract: A low odor, aqueous, quick acting cold temperature disinfectant solution primarily useful for medical instruments to disinfect within a half hour or less. The composition comprises a reacting or synergistic combination of hydrogen peroxide and from about 1% to 30% by weight of a carboxylic acid/carboxylate salt buffered solution.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: August 1, 2000
    Assignee: Healthpoint, Ltd.
    Inventors: Norman A. Miner, William H. Woller, Edward L. Anderson, David W. Hobson
  • Patent number: 6077460
    Abstract: The invention relates to the use of at least one compound of general formula (I), ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 independently of one another represent a hydrogen atom or an alkyl or alkenyl radical; R.sub.4 represents an alkyl or alkenyl radical, and n represents 1 to 5; or of an acid addition salt thereof, as an inhibitor of corrosion in the extraction, processing, storage and transportation of crude oil and natural gas, and to a process for the preparation of this compound.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: June 20, 2000
    Assignee: BASF Aktiengesellschaft
    Inventors: Knut Oppenlander, Gunter Oetter, Rudi Kroner, Norbert Mahr, Hans-Jurgen Jatzek, Klaus Taeger
  • Patent number: 6063334
    Abstract: The present disclosure is concerned with inhibiting corrosion in metal, usually steel, equipment which is exposed to oil field production flow including gases, oil, water, and sand. It is injected into the aqueous stream and carried with it to contact and coat the metal surfaces. It includes a corrosion inhibitor including at least one sulfur amine based on the equation:R--X(C.sub.2 H.sub.4 NZ).sub.n C.sub.2 H.sub.4 NYIn which R is a C12-36 hydrocarbon;X is an amide-CO--NH-- or 5 membered cyclic imidazoline ring;Z is H or Y; Y is SO.sub.2 ;and .sub.n is an integer from 1 to 8.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: May 16, 2000
    Assignee: Champion Technologies, Inc.
    Inventor: Ali Naraghi
  • Patent number: 6059992
    Abstract: Corrosion in aqueous alkanolamine, physical solvents, or combination of alkanolamine and physical solvent solutions used to remove acid gases from natural gas, synthetic gas, or light hydrocarbon streams can be reduced by addition of mixtures of oxygen scavengers or mixtures of oxygen scavengers and sodium molybdate. The oxygen scavengers must be promoted to reduce metal surfaces in contact with the solutions to a more passive, harder, and insoluble form at the operating temperature of the treating system. The sodium molybdate provides additional passivation especially in the imperfections on the surface of the metal where corrosion accelerates.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: May 9, 2000
    Inventors: Ray R. Veldman, David O. Trahan
  • Patent number: 6049002
    Abstract: The method for the preparation of aqueous solutions containing performic acid formed by reaction of formic acid and hydrogen peroxide n the presence of a catalyst, the catalyst being a compound containing at least one ester group and/or group (a) differing from a carboxylic acid group and an alcoholic group, preferably a carboxylic acid ester, and aqueous solutions containing performic acid, formic acid, hydrogen peroxide, and a compound containing at least one ester group and/or group (a) differing from a carboxylic acid group, and the use of such solutions.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: April 11, 2000
    Assignee: Kemira Chemicals B.V.
    Inventors: Tapio Mattila, deceased, Reijo Aksela
  • Patent number: 5993737
    Abstract: The invention provides for the treatment of raw water having a pH of 2.5 to 9, an alkalinity of at most 50 mg/l expressed as calcium carbonate, a calcium content of at most 100 mg/l expressed as calcium carbonate, and a positive calcium carbonate dissolution potential. The process comprises separating part of the water from the remainder thereof and acidifying the part to increase its calcium carbonate dissolution potential. The acidified water is then fed through a bed of particles comprising calcium carbonate where the water consumes part of the calcium carbonate thereby increasing the calcium content and the alkalinity of the water which issues from the bed. The water issuing from the bed is then mixed with the remainder of the raw water to obtain an at least partially treated product water having a positive calcium carbonate dissolution potential which is at least 2 mg/l calcium carbonate less than that of the raw water.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: November 30, 1999
    Assignee: Implico B.V.
    Inventors: Grant S. Mackintosh, Hendrik A. De Villiers
  • Patent number: 5993693
    Abstract: Zwitterionic water-soluble imine corrosion inhibitors of the general formula: ##STR1## wherein R.sup.3 is an anionically charged group. Preferred zwitterionic imines are the reaction products of the Michael addition of acrylic acid to an imine.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: November 30, 1999
    Assignee: Nalco/Exxon Energy Chemicals, L.P.
    Inventor: G. Richard Meyer
  • Patent number: 5989595
    Abstract: A composition of matter and the method of making that provides a low pH acidic composition that is useful for destroying microorganisms that are undesirable and useful for destroying or reducing melanoma on human skin. The composition and method include sulfuric acid combined with distilled water and ammonium sulfate under at least 15 psi pressure in a pressurized container, all of which is heated to around 1200.degree. F. for at least 3 hours. The final cooled mixture is stabilized with 10 percent of the original mixture. The resultant composition is useful for preserving food, such as fresh fish, and for skin treatment of melanoma.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: November 23, 1999
    Inventor: Barry W. Cummins
  • Patent number: 5916484
    Abstract: By the present invention, improved metal corrosion inhibited aqueous organic acid compositions and methods are provided. The compositions are basically comprised of water, an organic acid, a corrosion inhibitor comprising at least one rosin amine derivative and a low toxicity corrosion inhibitor intensifier selected from the group consisting of thioglycolic acid and derivatives thereof.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: June 29, 1999
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Michael M. Brezinski
  • Patent number: 5876662
    Abstract: An odor control system for removing hydrogen sulfide from a gas stream. In a first chamber, the gas stream is initially treated with NaOH at low pH for removal of about 70% of the H.sub.2 S. Unreacted NaOH and the reaction product Na.sub.2 S flow into a first sump while the initially treated gas stream flows into a second chamber, fluidly connected to a second sump. In the second chamber, the gas stream is scrubbed with a solution of NaOH and NaOCl for scrubbing of the remaining H.sub.2 S before the cleaned gas is exhausted to atmosphere. From the second chamber, unreacted NaOH and NaOCl, together with reaction products sulfur, Na.sub.2 SO.sub.4 and Na.sub.2 S flow into the second sump. The contents of the two sumps are flushed out separately by adding make up water to each of them. Each sump has a separate drain and each drain empties into a common drain where the Na.sub.2 S from the first sump reacts with unreacted NaOCl from the second sump to produce sulfur and Na.sub.2 SO.sub.4.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: March 2, 1999
    Assignee: US Filter/RJ Environmental, Inc.
    Inventor: Roop C. Jain
  • Patent number: 5871667
    Abstract: Aqueous ammoniate solutions made during the manufacture of N-hydrocarbyl thiophosphoric triamides, consisting essentially of aqueous solutions of ammonium chloride and ammonia containing a water-soluble impurity normally tending to engender corrosion of ferrous metal are rendered corrosion-resistant by dissolving therein a small corrosion-inhibiting amount (e.g., up to about 5000 ppm (wt/wt) of a water-soluble salt or oxide of zinc, aluminum, arsenic, antimony or bismuth.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: February 16, 1999
    Assignee: Albemarle Corporation
    Inventors: Chi Hung Cheng, Gerald M. Sulzer
  • Patent number: 5858798
    Abstract: Primary amines, ammonia, or mixtures thereof can be detected using a reagent comprising from about 650 ppm to about 25 percent by weight of phthalic dicarboxyaldehyde; from about 74 to about 99.88 percent by weight of an alkali metal borate; and, from about 550 ppm to about 22 percent by weight of a nucleophile.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: January 12, 1999
    Assignee: Nalco Chemical Company
    Inventors: Martin R. Godfrey, Donald E. Govoni, Linda M. Link
  • Patent number: 5853619
    Abstract: A low toxic corrosion inhibitor comprises (A) mercaptocarboxylic acid having from 2 to 6 carbon atoms, and (B) a polyamine/fatty acid/carboxylic acid adduct. The preferred combination of (A) and (B) includes mercaptoacetic acid and ethylenetetramine/tall oil acd/acrylic acid adduct.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: December 29, 1998
    Assignee: Nalco/Exxon Energy Chemicals, L.P.
    Inventors: James D. Watson, John G. Garcia, Jr.
  • Patent number: 5840343
    Abstract: Provided is an anti-microbial composition containing an ester of formic acid, an oxidizer, performic acid and water. Also provided is a premix for making the anti-microbial composition having two parts. One part contains the ester of formic acid and a second part contains the oxidizer. Another method is provided for making the anti-microbial composition in which the ester of formic acid is combined with the oxidizer and water. A further method is provided for sterilizing medical devices, including dialyzer filter modules, wherein the anti-microbial composition is capable of a 1:1 to a 1:12 dilution with water.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: November 24, 1998
    Assignee: Minntech Corporation
    Inventors: Robert T. Hall, II, Bradley K. Onstad, Daniel B. Carlsen
  • Patent number: 5830383
    Abstract: A method of treating an aqueous system is described which comprises incorporating in the system a hydroxylamine derivative of the general formula: ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 which may be the same or different represents hydrogen, alkyl of 1 to 8 carbon atoms or aryl or a water soluble salt thereof or a precursor thereof, and a tannin in a weight ratio of at least 2:1. This is particularly useful for boiler water systems.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: November 3, 1998
    Assignee: BetzDearborn Inc.
    Inventors: Brian Greaves, Stephen Clifford Poole, Chih Ming Hwa, Joseph Chwei-Jer Fan
  • Patent number: 5827542
    Abstract: A low odor, aqueous, quick acting room temperature disinfectant solution primarily useful for medical instruments to disinfect within a half hour or less. The composition comprises a reacting or synergistic combination of hydrogen peroxide and from about 1% to 30% by weight of a water soluble organic acid or salt form thereof with the acid preferably being selected from the group consisting of malonic and succinic acids.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: October 27, 1998
    Assignee: Healthpoint, Ltd.
    Inventors: Norman A. Miner, William H. Woller, Edward L. Anderson, David W Hobson
  • Patent number: 5792420
    Abstract: The present invention provides an improved metal corrosion inhibitor for use in aqueous acid solutions which is relatively non-toxic and inexpensive. The corrosion inhibitor is a mixture comprised of oligomerized aromatic amines prepared by contacting the still bottoms residue produced in the distillation of quinoline from coal tar with oxygen in the presence of a catalyst.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: August 11, 1998
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Michael M. Brezinski
  • Patent number: 5785896
    Abstract: A method of combating corrosion of a metal which comprises contacting such metal with a composition containing polyamino acids, their salts and their anhydrides, together with at least one corrosion inhibitor selected from the group consisting of benzotriazole, 4-C.sub.1 -C.sub.4 -alkylbenzotriazoles and 5-C.sub.1 -C.sub.4 -alkylbenzotriazoles.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: July 28, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Heinz-Joachim Rother, Franz Kunisch
  • Patent number: 5779939
    Abstract: Corrosion prevention compositions which contain lactobionic acid N-alkylamides, and further having a pH below 9.0, are described. In particular, lactobionic acid N-alkylamides in which the saturated or unsaturated alkyl group bonded via the amide function has a chain length of 8 to 18 carbon atoms show a good corrosion-inhibiting action. The use of lactobionic acid N-alkylamides in corrosion prevention compositions and metalworking compositions is also described.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: July 14, 1998
    Assignee: Solvay Deutschland GmbH
    Inventors: Klaus-Guenter Gerling, Helge Rau, Kornelia Wendler, Petra Schwarz, Karlheinz Uhlig
  • Patent number: 5779938
    Abstract: The invention is an effective, easy to produce, and economical corrosion inhibitor which can be used in a variety of environments. The corrosion inhibitor of the present invention is the salt of certain tertiary amines. The corrosion inhibitor is the reaction product of one or more tertiary amines and certain carboxylic acids, preferably a mixture of mercaptocarboxylic and carboxylic acids.
    Type: Grant
    Filed: August 24, 1995
    Date of Patent: July 14, 1998
    Assignee: Champion Technologies, Inc.
    Inventors: Ali Naraghi, Philippe Prince
  • Patent number: 5766548
    Abstract: Control of formation of heat stable amine salts and of corrosion in an amine solvent treating system is accomplished by introduction of N,N-diethylhydroxylamine catalyzed with hydroquinone into the system. The catalyzed N,N-diethylhydroxylamine is effective at the temperature ranges of amine treating systems to effectively reduce formation of heat stable amine salts and to inhibit corrosion. The catalyzed N,N-diethylhydroxylamine is effective in proportions including the range of about 0.5 to about 6 parts N,N-diethylhydroxylamine to 1 part hydroquinone.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: June 16, 1998
    Assignee: Cata Chem Inc.
    Inventor: John Soria
  • Patent number: 5756004
    Abstract: The present invention provides improved quaternary ammonium compounds useful as metal corrosion inhibitors in aqueous acid solutions, methods of preparing the compounds, metal corrosion inhibited aqueous acid solutions containing the compounds and methods of protecting metal surfaces from acid corrosion using the compounds. The compounds are prepared by contacting the still bottoms residue produced in the distillation of quinoline from coal tar with oxygen to oligomerize aromatic amines contained therein and then reacting the oligomerized amines with a benzylhalide.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: May 26, 1998
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Michael M. Brezinski
  • Patent number: 5756003
    Abstract: Corrosion prevention compositions which contain lactobionic acid N-alkylamides are described. In particular, lactobionic acid N-alkylamides in which the saturated or unsaturated alkyl group bonded via the amide function has a chain length of 8 to 18 carbon atoms show a good corrosion-inhibiting action. The use of lactobionic acid N-alkylamides in corrosion prevention compositions and metalworking compositions is also described.
    Type: Grant
    Filed: February 4, 1997
    Date of Patent: May 26, 1998
    Assignee: Solvay Deutschland GmbH
    Inventors: Klaus-Guenter Gerling, Helge Rau, Kornelia Wendler, Petra Schwarz, Karlheinz Uhlig
  • Patent number: 5720902
    Abstract: Disclosed are methods and compositions for inhibiting the corrosion of low carbon steel in contact with aqueous systems. The composition comprises a silicon compound containing a hydrolyzable group, a complex fluoro acid, and a cross-linking agent.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: February 24, 1998
    Assignee: BetzDearborn Inc.
    Inventors: Suzanne M. Zefferi, Edward A. Rodzewich
  • Patent number: 5708108
    Abstract: A polymer and method of controlling corrosion and the formation and deposition of scale imparting compounds in water systems is disclosed. The polymer has the general structure: ##STR1## wherein E.sup.1 comprises the repeat unit obtained after polymerization an .alpha.,.beta. ethylenically unsaturated carboxylic acid monomers, lower alkyl (C.sub.1 -C.sub.6) ester or a hydroxylated lower alkyl (C.sub.1 -C.sub.6) ester of such carboxylic acid, or amide forms thereof; E.sup.2 comprises the repeat unit obtained after polymerization of an .alpha.,.beta. ethylenically unsaturated monomer containing a sulfonic acid functionality; R.sup.1 is a hydrogen or a lower (C.sub.1 -C.sub.3) alkyl; R.sup.2 is --CH.sub.2 --O-- or --C(.dbd.O)--O--; R.sup.3 is --?--CH.sub.2 --CH(--CH.sub.2 --OH)--O--!--.sub.n ; n is an integer greater than 1; and R.sup.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: January 13, 1998
    Assignee: BetzDearborn Inc.
    Inventors: William S. Carey, Andrew Solov
  • Patent number: 5665242
    Abstract: A method for controlling fouling of a flashing vessel or heat-exchange surface exposed to a high-enthalpy geothermal brine tending to form silicon-containing scale. The method adds a silicon-complexing amount of fluoroborate species to the brine to form a fluid mixture that does not produce substantial amounts of the scale when the temperature of the fluid mixture is reduced. The addition does not significantly increase corrosion rates of mild steel heat-exchanger materials of construction.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: September 9, 1997
    Assignee: Union Oil Company of California
    Inventor: Darrell L. Gallup
  • Patent number: 5643534
    Abstract: A method for inhibiting corrosion of metals in contact with an aqueous alkanolamine solution in an amine unit for removing of acid gases from a hydrocarbon, comprising adding to the solution a sufficient amount of a corrosion-inhibiting composition comprising a blend of salicylic acid with a reaction product of maleated tall oil fatty acid polyhydroxy polyalkane and ammonium or potassium hydroxide; tallow diamine quaternary dichloride or alkanediol or mixtures thereof, and alkanol or alkanolamine. The blend may be diluted in water and may optionally include an antifoam material.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: July 1, 1997
    Assignee: BetzDearborn Inc.
    Inventor: Ljiliana V. Minevski
  • Patent number: 5620653
    Abstract: An odor control system and method for removing unwanted odorous airborne constituents in which the gas stream is flowed through a compact, boxlike housing having a plurality of sequentially communicating treatment chambers. Gas stream pretreatment is accomplished in a first chamber, in fluid communication with a sump, as the gas flows through a packed bed wetted by suitable chemical reagents. After pretreatment, the gas stream is passed through downstream chambers, also utilizing wetted packed beds. These chambers are in fluid communication with a second, separate sump. Because of the first chamber/separate sump combination, influent gas treatment, by stages, can be accomplished. In this manner, different, contemporaneous chemical treatments are possible, within the single housing, with different chemical reagents utilized as needed. Such treatments are possible even in cases where otherwise incompatible chemical reagents are used.
    Type: Grant
    Filed: April 24, 1995
    Date of Patent: April 15, 1997
    Assignee: RJ Environmental, Inc.
    Inventors: Roop C. Jain, Martin Scanlan
  • Patent number: 5616616
    Abstract: Provided is an anti-microbial composition containing an ester of formic acid, an oxidizer, performic acid and water. Also provided is a premix for making the anti-microbial composition having two parts. One part contains the ester of formic acid and a second part contains the oxidizer. Another method is provided for making the anti-microbial composition in which the ester of formic acid is combined with the oxidizer and water.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: April 1, 1997
    Assignee: Minntech Corporation
    Inventors: Robert T. Hall, II, Bradley K. Onstad
  • Patent number: 5614028
    Abstract: An acid based cleaning and passivating treatment for metal surfaces is provided. The single step acid based cleaning and passivating is provided by incorporating a corrosion inhibiting amount of an ethoxylated tertiary dodecyl mercaptan into an acidic metal cleaner.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: March 25, 1997
    Assignee: BetzDearborn Inc.
    Inventor: Edward A. Rodzewich
  • Patent number: 5601754
    Abstract: A polymer and method of controlling corrosion and the formation and deposition of scale imparting compounds in water systems is disclosed. The polymer has the general structure: ##STR1## wherein E.sup.1 comprises the repeat unit obtained after polymerization of one or more .alpha., .beta. ethylenically unsaturated monomers, selected from the group consisting of a carboxylic 3acid, lower alkyl (C.sub.1 -C.sub.6) ester or a hydroxylated lower alkyl (C.sub.1 -C.sub.6) ester of such carboxylic acid, and amide forms thereof; E.sup.2 comprises the repeat unit obtained after polymerization of one or more .alpha., .beta. ethylenically unsaturated monomer containing a sulfonic acid functionality; R.sup.1 is a hydrogen or a lower (C.sub.1 -C.sub.3) alkyl; R.sup.2 is --CH.sub.2 -- O--or --C(.dbd.O)--O--; R.sup.3 is --(--CH.sub.2 --CH(--CH.sub.2 --OH)--O--)--.sub.n ; n is an integer greater than 1; and R.sup.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: February 11, 1997
    Assignee: Betz Laboratories, Inc.
    Inventors: William S. Carey, Andrew Solov
  • Patent number: 5589507
    Abstract: Provided is an anti-microbial composition containing an ester of formic acid, an oxidizer, performic acid and water. Also provided is a premix for making the anti-microbial composition having two parts. One part contains the ester of formic acid and a second part contains the oxidizer. Another method is provided for making the anti-microbial composition in which the ester of formic acid is combined with the oxidizer and water. Also provided is a method for sterilizing devices by contacting the surface of the device with the anti-microbial composition containing the ester of formic acid, an oxidizer, performic acid and water.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: December 31, 1996
    Assignee: Minntech Corporation
    Inventors: Robert T. Hall, II, Bradley K. Onstad
  • Patent number: 5587109
    Abstract: A method of treating an aqueous system is described which comprises incorporating in the system a hydroxylamine derivative of the general formula: ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 which may be the same or different represents hydrogen, alkyl of 1 to 8 carbon atoms or aryl or a water soluble salt thereof or a precursor thereof, and a tannin in a weight ratio of at least 2:1. This is particularly useful for boiler water systems.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: December 24, 1996
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Brian Greaves, Stephen C. Poole, Chih M. Hwa, Joseph C. Fan
  • Patent number: 5492629
    Abstract: A method for removing scale and stains from the interior surfaces of a water-containing system having a reservoir, auxiliary equipment and piping, without having to drain the water from the system. The use of inhibited mineral acid allows the water to be circulated throughout the entire system, cleaning all interior surfaces without damaging them. Once scale and stains are removed, the water is neutralized.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: February 20, 1996
    Assignee: H.E.R.C. Products Incorporated
    Inventors: Jerome H. Ludwig, Duane W. Sampson
  • Patent number: 5458849
    Abstract: Corrosion cracking and blistering of steels in contact with refinery streams containing cyanide is inhibited or prevented by treating said stream with a reaction product or products obtained by reacting morpholine and formaldehyde. The preferred corrosion cracking and blistering inhibiting treatment product is bis--morpholinyl-- methane.
    Type: Grant
    Filed: October 22, 1993
    Date of Patent: October 17, 1995
    Assignee: Nalco Chemical Company
    Inventors: Veronica K. Majestic, Manian Ramesh
  • Patent number: 5456767
    Abstract: A method for inhibiting corrosion of a metal surface in a liquid medium is described. The method comprises incorporating into the medium a corrosion inhibiting amount of a combination of a surfactant that forms a bilayer on the metal surface in the fluid and a corrosion inhibitor that solubilizes in the medium in the presence of the surfactant. The amount of surfactant is sufficient to produce a bilayer on the metal surface in the medium. The combination isa. an anionic surfactant that forms a bilayer on the metal surface and a cationic corrosion inhibitor;b. a cationic surfactant that forms a bilayer on the metal surface and an anionic corrosion inhibitor;c. an ionic surfactant that forms a bilayer on the metal surface and an ionic corrosion inhibitor having a pendent, generally straight chain hydrocarbon or substituted hydrocarbon moiety of from about 10 to about 18 carbon atoms; ord. an ionic surfactant that forms a bilayer on the metal surface and a non-ionic corrosion inhibitor.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: October 10, 1995
    Assignee: Petrolite Corporation
    Inventors: Sayed S. Shah, Thomas G. Braga, Bernardus A. Oude Alink, Jacob Mathew
  • Patent number: 5435808
    Abstract: A process for the curing of animal hides using a brine solution including the step of adding an effective bactericidal and flocculating amount of a composition comprising:10-30 wt. % acetic acid5-20 wt. % peracetic acid15-25 wt. % hydrogen peroxide1-10 wt. % phosphoric acidbalance waterOther peracids, such as, perlactic acid, percitric acid, perproprionic acid, perbenzoic acid, perpentenoic acid and perbutyric acid may be used.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: July 25, 1995
    Assignee: Birko Corporation
    Inventors: Frederick W. Holzhauer, Dana J. Johnson, Terry McAninch
  • Patent number: 5431877
    Abstract: An aqueous solution which contains ammonium polysulfide is proportionally added to the sour water, which contains cyanide ions, ammonium ions, and sulfide ions. At least part of the cyanide ions contained in the sour water is converted to thiocyanate ions by the ammonium polysulfide. The solution which contains ammonium polysulfide is prepared from an aqueous solution by oxidation in an electrochemical cell. That aqueous solution may consist entirely or in part of sour water.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: July 11, 1995
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Volker Brucken, Gert Ungar, Hans-Martin Stonner, Ernst Stoldt, Johann Schlauer, Nikola Anastasijevic, Eilhard Hillrichs
  • Patent number: 5425914
    Abstract: A method of inhibiting the corrosion of iron-based metallurgies in contact with cooling water systems under severe corrosion inducing conditions comprising adding to said cooling water an aqueous combination of an alcohol, an acid, a fatty imidazoline, and an ethoxylated fatty diamine.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: June 20, 1995
    Assignee: Betz Laboratories, Inc.
    Inventors: J. Michael Brown, Herbert A. Roberts, John J. Herrold
  • Patent number: 5411677
    Abstract: A corrosion inhibitor composition and a method for employing the same to prevent corrosion of copper and copper containing metals in contact are disclosed. Protection is afforded thereto by contacting the metal surface with the medium containing sufficient amount of benzotriazole/its derivatives and halogen, preferentially iodide or bromide ions. The inhibitor has particular utility in protecting metal surfaces which are subject to corrosion in aggressive aqueous systems.
    Type: Grant
    Filed: April 26, 1993
    Date of Patent: May 2, 1995
    Assignee: The Penn State Research Foundation
    Inventors: Howard W. Pickering, Yongchun Wu
  • Patent number: 5387393
    Abstract: Corrosion, cracking and blistering of steels in contact with water containing refinery streams contaminated with cyanide is inhibited or prevented by treating the streams with a cyanide reactive scavenger comprising at least one amine-aldehyde reaction product.
    Type: Grant
    Filed: September 8, 1993
    Date of Patent: February 7, 1995
    Assignee: Nalco Chemical Company
    Inventors: Veronica K. Braden, Manian Ramesh
  • Patent number: 5356548
    Abstract: Compounds of the formula ##STR1## wherein X is an anion selected from the group consisting of phosphate, borate and molybdate groups, and a method for making these compounds. The compounds are useful in the control of microorganisms in aqueous systems and in the inhibition of corrosion of metal surfaces in contact with aqueous systems.
    Type: Grant
    Filed: April 28, 1993
    Date of Patent: October 18, 1994
    Assignee: Buckman Laboratories International, Inc.
    Inventors: John D. Pera, S. Rao Rayudu
  • Patent number: 5330683
    Abstract: An environmentally acceptable and economically appealing method of inhibiting corrosion in brine solution systems wherein an aqueous brine solution is treated with gluconate or sorbitol.
    Type: Grant
    Filed: June 17, 1993
    Date of Patent: July 19, 1994
    Assignee: Nalco Chemical Company
    Inventor: Barry W. Sufrin
  • Patent number: 5314643
    Abstract: A process for the inhibition of corrosion caused by naphthenic acid and sulfur compounds during the elevated temperature processing of crude oil by use of a corrosion inhibitor consisting of trialkylphosphate and an alkaline earth metal phosphonate-phenate sulfide.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: May 24, 1994
    Assignee: Betz Laboratories, Inc.
    Inventors: James G. Edmondson, S. Blake Pruett
  • Patent number: 5292480
    Abstract: A corrosion inhibitor with excellent film forming and film persistency characteristics may be produced by first reacting C.sub.18 unsaturated fatty acids with maleic anhydride or fumaric acid to produce the fatty acid Diels-Alder adduct or the fatty acid-ene reaction product. This adduct or reaction product is further reacted in a condensation or hydrolysation reaction with a polyalcohol to form an acid-anhydride ester corrosion inhibitor. The ester may be reacted with amines, metal hydroxides, metal oxides, ammonia, and combinations thereof to neutralize the ester. Surfactants may be added to tailor the inhibitor formulation to meet the specific needs of the user (i.e., the corrosion inhibitor may be formulated to produce an oil-soluble, highly water-dispersible corrosion inhibitor or an oil-dispersible, water-soluble corrosion inhibitor). Suitable carrier solvents may be employed where needed to effectively disperse the corrosion inhibitor formulation.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: March 8, 1994
    Assignee: Westvaco Corporation
    Inventors: Eugene R. Fischer, John A. Alford, Paul G. Boyd
  • Patent number: 5275744
    Abstract: A composition of polyalkylenepolyamine derivatives useful as a corrosion inhibitor in aqueous media produced by reacting a starting polyalkylenepolyamine composition comprising a mixture of:(i) at least one C-alkyl-ethylene diamine; and(ii) at least one di-(C-alkyl)-diethylenetriamine;wherein each C-alkyl group on the ethylene diamine and diethylenetriamine independently contain between 8-26 carbon atoms;with a derivatizing agent which is either an alkylating agent or an alkylene oxide. Methods for preparing this composition and using it to inhibit the corrosion of corrodible metal alloys are also disclosed.
    Type: Grant
    Filed: September 9, 1992
    Date of Patent: January 4, 1994
    Assignee: Chevron Research and Technology Company
    Inventor: Andrew W. Ho
  • Patent number: 5268127
    Abstract: The present invention provides a method for inhibiting corrosion of carbon steel in contact with a mixture of hydrofluoric acid and tetrahydrothiophene-1,1-dioxide comprising adding a corrosion inhibiting amount of an alkali metal halide to said mixture of hydrofluoric acid and tetrahydrothiophene-1,1-dioxide.
    Type: Grant
    Filed: July 15, 1992
    Date of Patent: December 7, 1993
    Assignee: Mobil Oil Corporation
    Inventor: Yiing-Mei Wu
  • Patent number: 5252254
    Abstract: Sulfonated alkylphenol is added to crude oil at 5 to 200 ppm to inhibit naphthenic acid corrosion of ferrous metal process piping and equipment in contact with the crude oil at naphthenic acid corrosion conditions. There are disclosed corrosion-inhibited hydrocarbon fluids, an improvement in hot hydrocarbon processing with sulfonated alkylphenol, a method for inhibiting naphthenic acid corrosion therewith, and a method for catalytically processing hydrocarbons with sulfonated alkylphenol to avoid catalyst poisoning by iron compounds.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: October 12, 1993
    Assignee: Nalco Chemical Company
    Inventor: Elizabeth Babaian-Kibala
  • Patent number: 5230810
    Abstract: A process for controlling corrosion in a wet oxidation system by controlling the operating pH range within the system is described. A pH operating range is selected within which corrosion to the wet oxidation system is minimized. The pH within the wet oxidation system is monitored and a pH adjusting material is added to the waste material being treated to maintain the system pH within the selected pH operating range, thus minimizing corrosion.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: July 27, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Mark A. Clark, David A. Beula