Aqueous Acid Environment (i.e.,ph Less Than Or Equal To 4.1) Patents (Class 422/12)
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Patent number: 6143243Abstract: This invention relates to a method of inhibiting the cavitation-erosion corrosion of aluminum surfaces. The method comprises the step of contacting the aluminum surface with a formulation comprising a corrosion inhibitor composition comprising one or more carboxylic acids, or salts or isomers thereof, and a polymerizable-acid graft polymer which comprises an unsaturated grafting acid and an alkylene oxide polymer, or copolymers thereof. This method has been demonstrated to be a surprisingly effective means to inhibit cavitation-erosion corrosion of aluminum surfaces found in the cooling systems of internal combustion engines.Type: GrantFiled: December 29, 1997Date of Patent: November 7, 2000Assignee: Prestone Products CorporationInventors: Aleksei V. Gershun, Peter M. Woyciesjes
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Patent number: 6120619Abstract: To avoid the corrosion of stainless steels in organosulphonic acid medium, at least one oxidizing agent selected from cerium(IV), iron(III), molybdenum(VI) or vanadium(V) oxides or salts, nitrites and persulphates, is added to the medium in an amount which is sufficient to place the spontaneous potential between the passivation and transpassivation potentials.Type: GrantFiled: January 12, 1999Date of Patent: September 19, 2000Assignee: Elf Atochem, S.A.Inventors: Jean Goudiakas, Guy Rousseau
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Patent number: 6106770Abstract: A method for preventing obstruction in aluminum brass pipes in a water flow path, including the steps of continuously supplying iron ions or an iron ion supply compound to water in the water flow path in such a manner that a concentration of iron ions in the water is 0.005 to 0.05 mg/liter, and supplying hydrogen peroxide or a hydrogen peroxide supply compound for a period of time sufficient for preventing adhesion of organisms to the aluminum brass pipes but not impeditive to formation of corrosion-resistant coating inside the pipes, in such a manner that a concentration of hydrogen peroxide in the water is 0.1 to 1.5 mg/liter, whereby corrosion of aluminum brass pipes and adhesion of organisms to the pipes are prevented.Type: GrantFiled: July 6, 1998Date of Patent: August 22, 2000Assignees: Mitsubishi Gas Chemical Company Inc., Katayama Chemical Inc.Inventors: Keiji Ohki, Kunio Nishimura, Yoshiharu Wakao
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Patent number: 6103144Abstract: 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: GrantFiled: April 12, 1999Date of Patent: August 15, 2000Assignee: BetzDearborn Inc.Inventor: Longchun Cheng
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Patent number: 6096348Abstract: 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: GrantFiled: July 29, 1998Date of Patent: August 1, 2000Assignee: Healthpoint, Ltd.Inventors: Norman A. Miner, William H. Woller, Edward L. Anderson, David W. Hobson
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Patent number: 6077460Abstract: 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: GrantFiled: January 13, 1999Date of Patent: June 20, 2000Assignee: BASF AktiengesellschaftInventors: Knut Oppenlander, Gunter Oetter, Rudi Kroner, Norbert Mahr, Hans-Jurgen Jatzek, Klaus Taeger
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Patent number: 6063334Abstract: 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: GrantFiled: March 6, 1998Date of Patent: May 16, 2000Assignee: Champion Technologies, Inc.Inventor: Ali Naraghi
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Patent number: 6059992Abstract: 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: GrantFiled: October 14, 1997Date of Patent: May 9, 2000Inventors: Ray R. Veldman, David O. Trahan
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Patent number: 6049002Abstract: 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: GrantFiled: October 28, 1996Date of Patent: April 11, 2000Assignee: Kemira Chemicals B.V.Inventors: Tapio Mattila, deceased, Reijo Aksela
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Patent number: 5993693Abstract: 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: GrantFiled: November 9, 1998Date of Patent: November 30, 1999Assignee: Nalco/Exxon Energy Chemicals, L.P.Inventor: G. Richard Meyer
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Patent number: 5993737Abstract: 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: GrantFiled: October 24, 1997Date of Patent: November 30, 1999Assignee: Implico B.V.Inventors: Grant S. Mackintosh, Hendrik A. De Villiers
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Patent number: 5989595Abstract: 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: GrantFiled: March 8, 1996Date of Patent: November 23, 1999Inventor: Barry W. Cummins
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Patent number: 5916484Abstract: 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: GrantFiled: May 13, 1997Date of Patent: June 29, 1999Assignee: Halliburton Energy Services, Inc.Inventor: Michael M. Brezinski
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Patent number: 5876662Abstract: 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: GrantFiled: February 3, 1997Date of Patent: March 2, 1999Assignee: US Filter/RJ Environmental, Inc.Inventor: Roop C. Jain
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Patent number: 5871667Abstract: 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: GrantFiled: January 21, 1997Date of Patent: February 16, 1999Assignee: Albemarle CorporationInventors: Chi Hung Cheng, Gerald M. Sulzer
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Patent number: 5858798Abstract: 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: GrantFiled: July 12, 1996Date of Patent: January 12, 1999Assignee: Nalco Chemical CompanyInventors: Martin R. Godfrey, Donald E. Govoni, Linda M. Link
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Patent number: 5853619Abstract: 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: GrantFiled: November 22, 1996Date of Patent: December 29, 1998Assignee: Nalco/Exxon Energy Chemicals, L.P.Inventors: James D. Watson, John G. Garcia, Jr.
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Patent number: 5840343Abstract: 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: GrantFiled: April 8, 1997Date of Patent: November 24, 1998Assignee: Minntech CorporationInventors: Robert T. Hall, II, Bradley K. Onstad, Daniel B. Carlsen
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Patent number: 5830383Abstract: 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: GrantFiled: April 19, 1995Date of Patent: November 3, 1998Assignee: BetzDearborn Inc.Inventors: Brian Greaves, Stephen Clifford Poole, Chih Ming Hwa, Joseph Chwei-Jer Fan
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Patent number: 5827542Abstract: 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: GrantFiled: February 12, 1996Date of Patent: October 27, 1998Assignee: Healthpoint, Ltd.Inventors: Norman A. Miner, William H. Woller, Edward L. Anderson, David W Hobson
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Patent number: 5792420Abstract: 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: GrantFiled: May 13, 1997Date of Patent: August 11, 1998Assignee: Halliburton Energy Services, Inc.Inventor: Michael M. Brezinski
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Patent number: 5785896Abstract: 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: GrantFiled: October 31, 1995Date of Patent: July 28, 1998Assignee: Bayer AktiengesellschaftInventors: Heinz-Joachim Rother, Franz Kunisch
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Patent number: 5779938Abstract: 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: GrantFiled: August 24, 1995Date of Patent: July 14, 1998Assignee: Champion Technologies, Inc.Inventors: Ali Naraghi, Philippe Prince
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Patent number: 5779939Abstract: 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: GrantFiled: February 13, 1996Date of Patent: July 14, 1998Assignee: Solvay Deutschland GmbHInventors: Klaus-Guenter Gerling, Helge Rau, Kornelia Wendler, Petra Schwarz, Karlheinz Uhlig
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Patent number: 5766548Abstract: 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: GrantFiled: March 31, 1997Date of Patent: June 16, 1998Assignee: Cata Chem Inc.Inventor: John Soria
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Patent number: 5756003Abstract: 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: GrantFiled: February 4, 1997Date of Patent: May 26, 1998Assignee: Solvay Deutschland GmbHInventors: Klaus-Guenter Gerling, Helge Rau, Kornelia Wendler, Petra Schwarz, Karlheinz Uhlig
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Patent number: 5756004Abstract: 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: GrantFiled: May 13, 1997Date of Patent: May 26, 1998Assignee: Halliburton Energy Services, Inc.Inventor: Michael M. Brezinski
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Patent number: 5720902Abstract: 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: GrantFiled: September 21, 1995Date of Patent: February 24, 1998Assignee: BetzDearborn Inc.Inventors: Suzanne M. Zefferi, Edward A. Rodzewich
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Patent number: 5708108Abstract: 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: GrantFiled: May 3, 1996Date of Patent: January 13, 1998Assignee: BetzDearborn Inc.Inventors: William S. Carey, Andrew Solov
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Patent number: 5665242Abstract: 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: GrantFiled: August 25, 1995Date of Patent: September 9, 1997Assignee: Union Oil Company of CaliforniaInventor: Darrell L. Gallup
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Patent number: 5643534Abstract: 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: GrantFiled: July 20, 1995Date of Patent: July 1, 1997Assignee: BetzDearborn Inc.Inventor: Ljiliana V. Minevski
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Patent number: 5620653Abstract: 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: GrantFiled: April 24, 1995Date of Patent: April 15, 1997Assignee: RJ Environmental, Inc.Inventors: Roop C. Jain, Martin Scanlan
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Patent number: 5616616Abstract: 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: GrantFiled: June 1, 1994Date of Patent: April 1, 1997Assignee: Minntech CorporationInventors: Robert T. Hall, II, Bradley K. Onstad
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Patent number: 5614028Abstract: 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: GrantFiled: May 31, 1995Date of Patent: March 25, 1997Assignee: BetzDearborn Inc.Inventor: Edward A. Rodzewich
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Patent number: 5601754Abstract: 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: GrantFiled: April 21, 1995Date of Patent: February 11, 1997Assignee: Betz Laboratories, Inc.Inventors: William S. Carey, Andrew Solov
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Patent number: 5589507Abstract: 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: GrantFiled: November 17, 1995Date of Patent: December 31, 1996Assignee: Minntech CorporationInventors: Robert T. Hall, II, Bradley K. Onstad
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Patent number: 5587109Abstract: 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: GrantFiled: April 19, 1995Date of Patent: December 24, 1996Assignee: W. R. Grace & Co.-Conn.Inventors: Brian Greaves, Stephen C. Poole, Chih M. Hwa, Joseph C. Fan
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Patent number: 5492629Abstract: 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: GrantFiled: October 12, 1993Date of Patent: February 20, 1996Assignee: H.E.R.C. Products IncorporatedInventors: Jerome H. Ludwig, Duane W. Sampson
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Patent number: 5458849Abstract: 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: GrantFiled: October 22, 1993Date of Patent: October 17, 1995Assignee: Nalco Chemical CompanyInventors: Veronica K. Majestic, Manian Ramesh
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Patent number: 5456767Abstract: 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: GrantFiled: October 15, 1993Date of Patent: October 10, 1995Assignee: Petrolite CorporationInventors: Sayed S. Shah, Thomas G. Braga, Bernardus A. Oude Alink, Jacob Mathew
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Patent number: 5435808Abstract: 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: GrantFiled: December 17, 1993Date of Patent: July 25, 1995Assignee: Birko CorporationInventors: Frederick W. Holzhauer, Dana J. Johnson, Terry McAninch
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Patent number: 5431877Abstract: 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: GrantFiled: March 2, 1994Date of Patent: July 11, 1995Assignee: Metallgesellschaft AktiengesellschaftInventors: Volker Brucken, Gert Ungar, Hans-Martin Stonner, Ernst Stoldt, Johann Schlauer, Nikola Anastasijevic, Eilhard Hillrichs
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Patent number: 5425914Abstract: 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: GrantFiled: March 22, 1994Date of Patent: June 20, 1995Assignee: Betz Laboratories, Inc.Inventors: J. Michael Brown, Herbert A. Roberts, John J. Herrold
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Patent number: 5411677Abstract: 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: GrantFiled: April 26, 1993Date of Patent: May 2, 1995Assignee: The Penn State Research FoundationInventors: Howard W. Pickering, Yongchun Wu
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Patent number: 5387393Abstract: 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: GrantFiled: September 8, 1993Date of Patent: February 7, 1995Assignee: Nalco Chemical CompanyInventors: Veronica K. Braden, Manian Ramesh
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Patent number: 5356548Abstract: 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: GrantFiled: April 28, 1993Date of Patent: October 18, 1994Assignee: Buckman Laboratories International, Inc.Inventors: John D. Pera, S. Rao Rayudu
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Patent number: 5330683Abstract: 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: GrantFiled: June 17, 1993Date of Patent: July 19, 1994Assignee: Nalco Chemical CompanyInventor: Barry W. Sufrin
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Patent number: 5314643Abstract: 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: GrantFiled: March 29, 1993Date of Patent: May 24, 1994Assignee: Betz Laboratories, Inc.Inventors: James G. Edmondson, S. Blake Pruett
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Patent number: 5292480Abstract: 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: GrantFiled: April 12, 1993Date of Patent: March 8, 1994Assignee: Westvaco CorporationInventors: Eugene R. Fischer, John A. Alford, Paul G. Boyd
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Patent number: 5275744Abstract: 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: GrantFiled: September 9, 1992Date of Patent: January 4, 1994Assignee: Chevron Research and Technology CompanyInventor: Andrew W. Ho