Using Inorganic Silicon Or Phosphorus Compound Patents (Class 422/18)
-
Patent number: 5376331Abstract: A method of inhibiting the pitting corrosion rate of carbon steel in a cooling tower system comprising adding to a cooling tower water an effective amount of a corrosion inhibiting composition containing from about 1 to about 10 ppm of a water soluble molybdate, calculated as molybdate and from about 5 to about 25 ppm of a stabilized phosphate, calculated as phosphate, the corrosion inhibiting composition being substantially free of active zinc, and circulating the water in the system.Type: GrantFiled: April 16, 1993Date of Patent: December 27, 1994Assignee: Gulf Coast Performance Chemical, Inc.Inventors: Bradley A. Bucher, Jesse H. Jefferies
-
Patent number: 5372748Abstract: Process for inhibiting the corrosive characteristics of a nitrogenous fertilizing solution comprising incorporating in said nitrogenous fertilizing solution at the moment of its constitution, about 50 to about 150 ppm of at least one of the linear esters of acid phosphates having the formulae; ##STR1## wherein R1 and R2 which are identical or different from one another, are selected from the group consisting of the n-heptyl, n-octyl, n-nonyl and n-decyl radicals.Type: GrantFiled: April 7, 1993Date of Patent: December 13, 1994Assignee: CFPIInventors: Joseph Schapira, Jean-Claude Cheminaud, Pascal Petitbon, Dominique Imbert
-
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
-
Patent number: 5320779Abstract: A corrosion inhibitor treatment composition for cooling water systems is disclosed in which no chromate is used and no free orthophosphate is present comprising a combination of a localized corrosion inhibitor in the form of a salt of molybdenum, vanadium, or tungsten, a general corrosion and scale inhibitor comprising zinc or nickel, a pair of organic phosphonates, and a stabilizing agent.Type: GrantFiled: June 6, 1991Date of Patent: June 14, 1994Assignee: Nalco Chemical CompanyInventor: Kenneth P. Fivizzani
-
Patent number: 5266228Abstract: Non-corrosive anti-freeze solutions for automotive cooling systems include an anti-corrosive effective amount of a sodium silicate corrosion inhibitor. The sodium silicate has an unusually low ratio of silica to sodium oxide of greater than 1.0 to about 2.5. This relatively low ratio of silica to sodium oxide prevents gelation from occurring while maintaining maximum anti-corrosive effectiveness of alcohol-based solutions containing the same.Type: GrantFiled: August 29, 1991Date of Patent: November 30, 1993Assignee: BASF CorporationInventors: Stanley T. Hirozawa, David E. Turcotte
-
Patent number: 5262078Abstract: Non-corrosive anti-freeze solutions for automotive cooling systems include an anti-corrosive effective amount of a sodium silicate corrosion inhibitor, and sodium nitrate. The sodium silicate has an unusually low ratio of silica to sodium oxide of greater than 1.0 to about 2.4. This relatively low ratio of silica to sodium oxide prevents gelation from occurring while the synergistic combination of the sodium silicate and sodium nitrate maintains maximum anti-corrosive effectiveness of alcohol-based solutions containing the same.Type: GrantFiled: April 12, 1991Date of Patent: November 16, 1993Assignee: BASF CorporationInventors: Stanley T. Hirozawa, David E. Turcotte
-
Patent number: 5246607Abstract: Methylpolysiloxanes are disclosed which have quaternary ammonium groups linked to silicon atoms via carbon atoms, wherein the ratio of the number of dimethylsiloxy groups to the number of quaternary ammonium groups has a value of 0.5 to 1.5. The methylpolysiloxanes are useful as corrosion inhibitors for preparations consisting predominantly of water, especially coolants, such as cooling lubricants mixed with water, in an amount of 0.01 to 0.1% by weight, based on the total preparation in the form suitable for use.Type: GrantFiled: October 12, 1989Date of Patent: September 21, 1993Assignee: Th. Goldschmidt AGInventors: Dietmar Schaefer, Werner Hohner
-
Patent number: 5232629Abstract: An orthophosphate salt and sodium silicate, when used in a 3:1 ratio by weight, and in a concentration of 0.1 to 100 mg/L, are found to have a synergistic effect in controlling the corrosion of carbon steel in an aqueous system, e.g., a municipal water supply system. The synergistic combination is also useful in reducing lead solubility and leaching, and in stabilizing soluble iron and manganese and their reaction products.Type: GrantFiled: March 2, 1992Date of Patent: August 3, 1993Assignee: Calgon CorporationInventor: Bennett P. Boffardi
-
Patent number: 5229030Abstract: A method of inhibiting corrosion of metal surfaces in contact with an aqueous system, comprising contacting the metal surfaces with a telomer compound having the formula I: ##STR1## in which M is hydrogen or an alkali or alkaline earth metal ion, an ammonium ion or a quaternised amine radical; and n is an average integer ranging from 1 to 60.Type: GrantFiled: November 6, 1991Date of Patent: July 20, 1993Assignee: FMC CorporationInventors: Brian G. Clubley, Jan Rideout
-
Patent number: 5227133Abstract: A method of inhibiting the pitting corrosion rate of carbon steel in a cooling tower system comprising adding to a cooling tower water an effective amount of a corrosion inhibiting composition containing from about 1 to about 10 ppm of a water soluble molybdate, calculated as molybdate and from about 5 to about 25 ppm of a stabilized phosphate, calculated as phosphate, the corrosion inhibiting composition being substantially free of active zinc, and circulating the water in the system.Type: GrantFiled: November 24, 1992Date of Patent: July 13, 1993Assignee: Gulf Coast Performance Chemical, Inc.Inventors: Bradley A. Bucher, Jesse H. Jefferies
-
Patent number: 5192447Abstract: A corrosion inhibitor treatment composition for cooling water systems at elevated temperatures in which no chromate is used is disclosed, comprising a combination of a localized corrosion inhibitor in the form of a salt of molybdenum, vanadium, or tungsten, a reduced level of a general corrosion and scale inhibitor comprising zinc, nickel or a combination thereof, orthophosphate, an organic phosphonate, and a stabilizing agent.Type: GrantFiled: July 9, 1991Date of Patent: March 9, 1993Assignee: Nalco Chemical CompanyInventor: Kenneth P. Fivizzani
-
Patent number: 5166074Abstract: A method of detecting the initial concentration of a water-treatment chemical present in a diluted aqueous system, by (1) incorporating into the aqueous system, a mixture including a known amount of the active ingredient and a known amount of an ultra-violet sensitive compound having the formula (I): ##STR1## wherein halogen is chlorine or bromine; X is ##STR2## and a and b, independently are 0 or 1; M is hydrogen or an alkaline metal ion; and (2) detecting the concentration of the compound of formula I, by exposing to ultra-violet light a sample of the aqueous system so treated.Type: GrantFiled: November 7, 1990Date of Patent: November 24, 1992Inventors: Adrian M. Vessey, David S. Ryder
-
Synergistic combination of sodium silicate and orthophosphate for controlling carbon steel corrosion
Patent number: 5137657Abstract: An orthophosphate salt and sodium silicate, when used in a 3:1 ratio by weight, and in a concentration of 0.1 to 100 mg/L, are found to have a synergistic effect in controlling the corrosion of carbon steel in an aqueous system, e.g., a municipal water supply system. The synergistic combination is also useful in reducing lead solubility and leaching, and in stabilizing soluble iron and manganese and their reaction products.Type: GrantFiled: April 24, 1991Date of Patent: August 11, 1992Assignee: Merck & Co., Inc.Inventor: Bennett P. Boffardi -
Patent number: 5080863Abstract: Aqueous heat transfer apparatus contains a multicomponent corrosion protection system including a first component adapted to release a corrosion inhibitor on exposure to water under relatively milder conditions and a second component adapted to release a corrosion inhibitor on exposure to water under relatively severer conditions. The components may be open top compartments of a capsule, closed by means of covers of controlled release glass which dissolve in water at different rates.Type: GrantFiled: May 21, 1991Date of Patent: January 14, 1992Assignee: Alcan International LimitedInventor: Alan Gray
-
Patent number: 5076941Abstract: Monofluorophosphate salts, especially sodium monofluorophosphate (Na.sub.2 PO.sub.3 F), when added to potable water sources in concentrations between 0.1 mg/L and 500 mg/L, significantly reduces lead (Pb) leaching into said water, producing the double benefit of reducing lead solubility and thus content in drinking water, while at the same time adding fluoride to that drinking water, with the anticaries benefit that fluoridation provides.Type: GrantFiled: October 15, 1990Date of Patent: December 31, 1991Assignee: Calgon Corp.Inventors: Bennett P. Boffardi, Ann M. Sherbondy
-
Patent number: 5077008Abstract: Medical instruments, which may include brass, copper, aluminum, stainless steel, carbon steel, or plastic parts are sterilized or disinfected in an anti-microbial solution. The anti-microbial effect of a strong oxidizing agent, such as peracetic acid, is improved with a wetting agent. The solution further includes a triazole or other component for inhibiting the corrosion of copper and brass. Phosphates or other buffering agents adjust the oxidizing agent generally to a neutral pH for preventing the corrosion of steel. Molybdates or analogous compounds also buffer the pH and inhibit corrosion of aluminum by the oxidizing agent. The corrosion inhibiting is enhanced by the wetting agent. Optionally, a sequestering agent is provided for inhibiting hard water precipitation.Type: GrantFiled: August 8, 1988Date of Patent: December 31, 1991Assignee: Steris CorporationInventors: Raymond C. Kralovic, Duncan C. Badertscher
-
Patent number: 5064612Abstract: A composition and methods for use in oilfield waterflood systems are disclosed. The composition is comprised of a phosphonate, a copolymer, and a permanganate and is effective at inhibiting the corrosion of metallic systems in petroleum oilfields caused by chlorine dioxide. Methods of use of phosphonate and permanganate alone are also disclosed. Chlorine dioxide is used in oilfield waterflood systems to control sulfides and sulfate reducing bacteria. However, chlorine dioxide is highly corrovive to the metallic components in the processing equipment of an oilfield system. The most effective system currently used to inhibit corrosion caused by chlorine dioxide comprises chromates. However, chromates are highly toxic and their use throughout the country is becoming increasingly restricted.Type: GrantFiled: January 4, 1991Date of Patent: November 12, 1991Assignee: Betz Laboratories, Inc.Inventors: James G. Edmondson, E. Paul Holder
-
Patent number: 5064613Abstract: A method of treating surfaces in order to eliminate microbial growth by adding an antibacterially effective amount of an organosilicon quaternary ammonium silatrane compound to the surface in order to destroy bacteria and fungi. The preferred organosilicon quaternary ammonium silatrane compound has the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4, each represent a hydrogen atom or a methyl, ethyl, propyl, or butyl radical.Type: GrantFiled: November 3, 1989Date of Patent: November 12, 1991Assignee: Dow Corning CorporationInventors: Bruce S. Higgs, William C. White
-
Patent number: 5061373Abstract: A process is provided for controlling the emission of hydrogen sulfide from, and the growth of living organisms in, steam condensate cooling towers and catch basins used in conjunction with steam and condensate of steam derived from hydrogen sulfide-containing geothermal brine. The process comprises contacting the condensate, in a substantially continuous manner, with a small, substantially less-than-stoichiometric amount of an oxidizing biocide, such as trichloro-isocyanuric acid or oxidizing biocide, such as trichloro-isocyanuric acid or 1-bromo-3-chloro-5,5-dimethyl-hydantoin, which results in the oxidation of such hydrogen sulfide precursors as ammonium bisulfide in the condensate to a water-soluble sulfite and/or sulfate, and which slows the growth of organisms in the cooling tower and catch basin.Type: GrantFiled: July 29, 1988Date of Patent: October 29, 1991Assignee: Union Oil Company of CaliforniaInventor: Darrell L. Gallup
-
Patent number: 5049310Abstract: New zinc stabilizing polymers containing at least 5 mole percent of a monomer represented by the structure: ##STR1## wherein: R is independently, at each occurrence, chosen from H and lower (C.sub.1 -C.sub.4) alkyl groups;R' is a hydrocarbonaceous bridging group containing from 1-12 carbon atoms;X is chosen from --SO.sub.3 M, --OH, --COOM groups or mixtures thereof,M is hydrogen or some other cation species; andn ranges from 1-10,are described. Also, the use of these polymers in combination with zinc salts, and in further combination with phosphate salts, to inhibit corrosion of iron containing metals, and other metals, when these metals are exposed to industrial waters is demonstrated. Deposit control or scale inhibition on these metals exposed to industrial waters is also observed.Type: GrantFiled: October 10, 1989Date of Patent: September 17, 1991Assignee: Nalco Chemical CompanyInventors: Donald A. Johnson, John E. Hoots, Dodd W. Fong, Guy A. Crucil
-
Patent number: 4885136Abstract: A method of anticorrosive treatment for soft water boilers to prevent iron family metals from corrosion, especially from pitting corrosion, which is characterized by adding, to a boiler water system using soft water at a high temperature, (a) a specific amount of a phosphorus compound, (b) a specific amount of a carboxylic acid compound and (c) a specific amount of a metal compound.Type: GrantFiled: October 15, 1987Date of Patent: December 5, 1989Assignee: Katayama Chemical Works Co., Ltd.Inventors: Sakae Katayama, Hirohiko Katayama, Toshihiko Mukai, Yoshinari Kawasaki
-
Patent number: 4867944Abstract: A method of inhibiting corrosion in cooling tower systems comprising adding to a cooling tower water containing sulfides, hydrocarbons or mixtures thereof as contaminants a corrosion inhibiting composition containing a water-soluble zinc compound, a water-soluble molybdate, a water-soluble orthophosphate and a water-soluble polyphosphate.Type: GrantFiled: January 13, 1988Date of Patent: September 19, 1989Assignee: Gulf Coast Performance Chemical, Inc.Inventors: Bradley A. Bucher, Jesse H. Jefferies, Harold P. Templet
-
Patent number: 4849171Abstract: A corrosion inhibited sodium and calcium chloride composition preferably in granular form, which is uniformly coated with a minute to minor quantity of an inhibitor comprising chiefly superphosphate and a minor amount of magnesium oxide. There is also disclosed a method for inhibiting corrosion of sodium and calcium chloride which comprises supplying to the metal surface which is exposed to corrosive attack by sodium and calcium chloride, a minute quantity of an inhibitor comprising chiefly superphosphate and a minor amount of magnesium oxide. The magnesium oxide functions to cement the inhibitor as a tenacious coating on the salt granules, and also to enhance the effectiveness of the phosphate corrosion inhibition.Type: GrantFiled: February 9, 1987Date of Patent: July 18, 1989Inventor: Bruce Murray
-
Patent number: 4828796Abstract: A method of protecting the internal surface of a pipeline against corrosion resides in introducing into the pipeline a composition comprising 0.01 to 1 part of a phosphate and a silicate. The phosphate can be sodium polyphosphate or monosubstituted potassium phosphate. The silicate can be an alkaline metal silicate or silicon dioxide. The weight ratio of the phosphate to the silicate varies from 9-50:1, respectively, and the composition includes up to 100 parts of water. The composition is formed by fusing the phosphate and the silicate at a temperature of about 800 to 10000 degrees C. and cooling the fused composition until a vitreous structure is formed. The composition is then introduced into a pipeline containing water having a P.sub.2 O.sub.5 concentration of about 0.3 to 3.5 milligrams per liter.Type: GrantFiled: June 9, 1986Date of Patent: May 9, 1989Assignees: Inzhenerny, Tsentr, Po, Selskokhozyaistvenno Vodosnabheniju, I, Truboprovodam, Alma-atinsky, Institut, Inzhenero, Zheleznodorozhnogo Transporta, Institut Khimicheskikh, Nauk, Akademii, Nauk, KazakhskoiInventors: Viktor V. Shishkin, Yaroslav P. Sushkov, Duglas Z. Serazetdinov, Evgeny G. Lukin, Viktoria I. Kapralova, Tamara S. Polyanskaya, Ljubov I. Abramova, Jury P. Shapovalov, Viktor N. Oleinik, Nikolai F. Kryazhevskikh, Alexandr I. Chernyai
-
Patent number: 4820423Abstract: A method of preventing corrosion and scale formation on metals exposed to industrial recirculating waters having a pH ranging between about 7.0 to about 9.5, which consists essentially of adding to said industrial recirculating waters an effective amount of a combination of a water-soluble zinc salt, a nitrogen-containing N-alkylated acrylamide zinc complexing polymer and an orthophosphate ion source, wherein:(a) the weight ratio of zinc to nitrogen-containing zinc complexing polymer ranges between 1:1 to about 1:20;(b) the nitrogen-containing N-alkylated acrylamide zinc complexing polymer has a weight average molecular weight ranging between 2,000 to 25,000 and is selected form the group consisting of water-soluble copolymers and terpolymers containing at least two mole percent of an N-alkylated acrylamide monomer, wherein the nitrogen substituted alkyl group contains from 3-12 carbon atoms and wherein the N-alkyl group may be linear or branched.Type: GrantFiled: September 1, 1987Date of Patent: April 11, 1989Assignee: Nalco Chemical CompanyInventors: Guy A. Crucil, Laura J. Blaser
-
Patent number: 4797224Abstract: Water-soluble zinc:polymer complexes of nitrogen-containing polymers are useful in preventing corrosion in aqueous recirculating systems operating within the pH range of 7.0-9.5, when combined with orthophosphate ion sources.Type: GrantFiled: September 2, 1987Date of Patent: January 10, 1989Assignee: Nalco Chemical CompanyInventors: Guy A. Crucil, Laura J. Blaser
-
Patent number: 4778655Abstract: A method of treating an aqueous system is disclosed which comprises adding thereto a water-soluble zinc salt, a chelant and either a product containing at least one phosphorous-containing acid group and at least one carboxylic acid group or an acrylic, vinyl or allyl carboxylic acid polymer.Type: GrantFiled: October 20, 1986Date of Patent: October 18, 1988Assignee: W. R. Grace & Co.Inventor: Brian Greaves
-
Patent number: 4744949Abstract: A method for inhibiting corrosion in industrial cooling waters which contain hardness and a pH of at least 6.5, comprising using a water-soluble inorganic phosphate capable of inhibiting corrosion in an aqueous alkaline environment and a co- or terpolymer of acrylic acid and certain substituted acrylamides such as t-butyl acrylamide. A water-soluble organic phosphonate capable of inhibiting corrosion in an alkaline environment may be used as an adjunct for the phosphate.Type: GrantFiled: July 6, 1987Date of Patent: May 17, 1988Assignee: Nalco Chemical CompanyInventors: John E. Hoots, Guy A. Crucil, Ellen L. Johnson
-
Patent number: 4714564Abstract: A multifunctional corrosion inhibitor consisting essentially of an alkali metal borate, an alkali metal nitrate, an alkali metal nitrite, an alkali metal metasilicate, an alkali metal phosphate, mercaptobenzothiazole and at least one selected surfactant.Type: GrantFiled: April 21, 1982Date of Patent: December 22, 1987Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: Charles T. Lynch, Fred W. Vahldiek, Mohammad Khobaib
-
Patent number: 4692315Abstract: A method for inhibiting corrosion in an aqueous system is described which comprises adding to the system a corrosion inhibiting metal salt capable of forming a passivating film of a water insoluble salt of said metal at the cathode, and a substantially linear cationic polymer.Type: GrantFiled: April 17, 1985Date of Patent: September 8, 1987Assignee: Dearborn Chemicals LimitedInventors: Brian Greaves, Paul Ingham
-
Patent number: 4659480Abstract: Scale control polymers and methods of use are disclosed. The polymers are water soluble and are composed of repeat units formed from an .alpha., .beta.ethylenically unsaturated commpound, and repeat units formed from allyl alkylene phosphite ethers.Type: GrantFiled: January 3, 1986Date of Patent: April 21, 1987Assignee: Betz Laboratories, Inc.Inventors: Fu Chen, Keith A. Bair
-
Patent number: 4659481Abstract: A water soluble polymer composition is disclosed. The polymer has repeat units characterized by the structural formulae: ##STR1## wherein R.sub.1 is H or lower alkyl (C.sub.1 -C.sub.3); R.sub.2 is OH, OM, or NH.sub.2 ; M is a water soluble cation; R.sub.3 is a hydroxy substituted alkyl or alkylene radical having from 1 to 6 carbon atoms or a non-substituted alkyl or alkylene radical having from 1 to 6 carbon atoms; X is an anionic radical; Z is H or hydrogens or a water soluble cation or cations which together counterbalance the valence of X, and a is 0 or 1. The copolymer is effective in inhibiting the precipitation of certain scale forming salts, and also acts to inhibit corrosion of metal parts in contact with water systems.Type: GrantFiled: May 16, 1986Date of Patent: April 21, 1987Assignee: Betz Laboratories Inc.Inventor: Fu Chen
-
Patent number: 4613450Abstract: This invention relates to a corrosion inhibitor for protecting metallic surfaces which are in contact with water, in particular circuits, apparatus and devices which use water as energetic or thermic fluid, said corrosion inhibitor being a fluorophosphate compound selected from the group consisting of:(i) compound of the formula M.sub.2.sup.I PO.sub.3 F, xH.sub.2 O(ii) compound of the formula LiM.sup.I PO.sub.3 F, xH.sub.2 O(iii) compound of the formula NaM.sup.I PO.sub.3 F, xH.sub.2 O(iv) compound of the formula M.sup.II PO.sub.3 F, xH.sub.2 O(v) compound of the formula M.sub.2.sup.I M.sup.II (PO.sub.3 F).sub.2, xH.sub.2 O(vi) compound of the formula M.sup.I PO.sub.2 F.sub.2, xH.sub.2 O(vii) compound of the formula M.sup.II (PO.sub.2 F.sub.2).sub.2, x H.sub.2 O(wherein M.sup.I is Na, K, Rb, Cs or HN.sub.4 ; M.sup.II is Mg, Ca, Ba, Sr, Zn, Cd, Mn, Ni or Co; and x is an integer or a fractional number comprised between 0 and 6) and(viii) mixtures thereof.Type: GrantFiled: March 25, 1985Date of Patent: September 23, 1986Assignee: Union Chimique et Industrielle de l'OuestInventors: Francis Moran, Sylvain Rocher, Louis Cot, Francis Dabosi, Michel Duprat, Jean Durand
-
Patent number: 4584104Abstract: A method of inhibiting amorphous silica scale formation on surfaces in contact with industrial waters containing dissolved silicates is disclosed. The method involves treating the industrial waters with a boron compound which dissolves in or hydrolyzes in these industrial waters to give the orthoborate ion. The preferred boron compound is boric acid, its salts, or precursors.Type: GrantFiled: June 29, 1984Date of Patent: April 22, 1986Assignee: Nalco Chemical CompanyInventor: Leonard Dubin
-
Patent number: 4560481Abstract: A method of inhibiting corrosion and controlling deposition in aqueous mediums, such as in cooling water systems, wherein iron containing well water is used as a water make-up source, is disclosed. The method comprises addition of certain water soluble acrylic acid type/allyl hydroxy propyl sulfonate ether copolymers to the desired aqueous medium.Type: GrantFiled: December 13, 1984Date of Patent: December 24, 1985Assignee: Betz Laboratories, Inc.Inventor: Orin Hollander
-
Patent number: 4548787Abstract: Compositions for inhibiting mineral scale and the corrosion of metals particularly the cavitation corrosion of aluminum in the presence of aqueous liquids are disclosed. The combination of a water-soluble phosphate with at least one of a water-soluble molybdate, tungstate, or selenate is disclosed as providing a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids.Type: GrantFiled: February 9, 1983Date of Patent: October 22, 1985Assignee: BASF Wyandotte CorporationInventors: Joe C. Wilson, Stanley T. Hirozawa, John J. Conville
-
Patent number: 4512915Abstract: A composition for inhibiting corrosion by water of metal substrates comprises zinc gluconate or glucoheptonate and at least one water-soluble inorganic polyphosphate.Type: GrantFiled: August 24, 1982Date of Patent: April 23, 1985Assignee: Roquette FreresInventors: Jean-Claude Lumaret, Serge Gosset, Michel Huchette
-
Patent number: 4508684Abstract: A method is disclosed of protecting heated aluminum based metals subject to heat transfer through the metal to a circulating aqueous cooling solution in contact therewith. The initially constituted cooling solution contains an alkali metal silicate in an adjusted amount above 0.2 gram per liter. The solution while functioning in the cooling system is then exposed to an alkali metal silicate glass causing the glass to progressively dissolve and stabilize the silicate at a level of at least 0.1 gram per liter. The initially prepared solution may also contain ethylene or propylene glycol, alkali metal phosphates and tetraborates in a ratio greater than 4:1, and nitrate, mercaptobenzothiazole or tolyltriazole.Type: GrantFiled: September 8, 1981Date of Patent: April 2, 1985Assignee: Ford Motor CompanyInventors: John Huff, Ronald R. Wiggle, Vladimir Hospadaruk
-
Patent number: 4502978Abstract: A method of enhancing corrosion inhibition of inorganic corrosion inhibitors, particularly stabilized phosphate corrosion inhibitors, when used in high hardness waters containing at least 800 ppm total hardness which comprises adding to the high hardness waters a combined product which includes both the inorganic corrosion inhibitor system and an effective amount of a water-soluble acrylic acid:acrylamide copolymer having an acrylic acid:acrylamide weight ratio between 1:4 and 1:2 and having a molecular weight between 1,000-25,000.Type: GrantFiled: November 8, 1982Date of Patent: March 5, 1985Assignee: Nalco Chemical CompanyInventors: John A. Romberger, Daniel A. Meier
-
Patent number: 4500445Abstract: This invention relates to the use of phospho-compositions, for example phosphates, pyrophosphates, polyphosphates, organophosphates, etc., as corrosion inhibitors in oxygen-containing aqueous systems of particulate matter such as slurries of solids, such as coal, etc.Type: GrantFiled: March 10, 1982Date of Patent: February 19, 1985Assignee: Petrolite CorporationInventors: Eddie French, Thomas G. Braga
-
Patent number: 4470890Abstract: A method is provided for preventing the dissolution of transition metal-based cathodes used in chlor-alkali diaphragm cells by adding a small amount of a corrosion inhibitor, such as sodium silicate or trisodium phosphate, to the electrolytic solution during periods of interrupted current flow to the cell. The corrosion inhibitor is adsorbed on the surface of the cathode and forms an adherent protective film on the cathode. This film protects the cathode by preventing dissolution of the transition metal in the cathode coating due to oxidation by sodium hypochlorite.Type: GrantFiled: December 21, 1981Date of Patent: September 11, 1984Assignee: Occidental Chemical CorporationInventors: Tilak V. Bommaraju, Krishnan Viswanathan
-
Patent number: 4452758Abstract: Antifreeze compositions and a process for inhibiting the corrosion of aluminum in contact with aqueous liquids are disclosed. The antifreeze compositions comprise a combination of an alkanolamine, an alkali metal phosphate, a heterocyclic nitrogen compound, as defined, and a conventional corrosion inhibitor in effective corrosion inhibiting amounts. The aqueous liquid can be an alcohol such as ethylene glycol.Type: GrantFiled: May 16, 1983Date of Patent: June 5, 1984Assignee: BASF Wyandotte CorporationInventors: Joe C. Wilson, Stanley T. Hirozawa, Stephen E. Eisenstein, Jerrold F. Maxwell
-
Patent number: 4440721Abstract: Compositions for inhibiting mineral scale and the corrosion of metals particularly the cavitation corrosion of aluminum in the presence of aqueous liquids are disclosed. The combination of a water-soluble phosphate with at least one of a water-soluble molybdate, tungstate, or selenate is disclosed as providing a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids.Type: GrantFiled: February 11, 1983Date of Patent: April 3, 1984Assignee: BASF Wyandotte CorporationInventors: Joe C. Wilson, Stanley T. Hirozawa, John J. Conville
-
Patent number: 4436628Abstract: The instant invention is directed to a process for the inhibition of scale and corrosion formation in an aqueous system, comprising adding to the system about 0.1 to 100 ppm, by weight based on the total aqueous content of said system, of 103 to 115% polyphosphoric acid, or neutral salts thereof.Type: GrantFiled: September 20, 1982Date of Patent: March 13, 1984Assignee: Calgon CorporationInventors: Paul H. Ralston, Sandra L. Whitney
-
Patent number: 4414126Abstract: Compositions and method of using said compositions for inhibiting the corrosion of high lead solder in aqueous systems are disclosed. Alkali metal aliphatic phosphonates in combination with alkali metal mercaptobenzothiazoles are effective inhibitors for the corrosion of high lead solder in aqueous systems.Type: GrantFiled: October 22, 1981Date of Patent: November 8, 1983Assignee: BASF Wyandotte CorporationInventor: Joe C. Wilson
-
Patent number: 4409121Abstract: Corrosion and scale-inhibiting compositions which are useful in recirculating aqueous systems comprise a mixture of a phosphate compound, a phosphonate compound comprising 1-hydroxyethylidene-1,1-diphosphonic acid or nitrilotris(methylene)triphosphonic acid, an aryl triazole, and a salt of a metal selected from the group consisting of molybdenum, tungsten and chromium. In the preferred embodiment of the invention, the phosphate compound is present in a weight percent ratio in the range of from about 2.5:1 to about 4:1 weight percent per weight percent of the metal salt. An example of an effective anti-corrosion composition comprises a mixture of sodium tripolyphosphate, 1-hydroxyethylidene-1,1-diphosphonic acid, benzotriazole and sodium molybdate, said composition being present in an amount of from about 5 to about 5,000 ppm.Type: GrantFiled: June 28, 1982Date of Patent: October 11, 1983Assignee: UOP Inc.Inventors: Edwin J. Latos, John C. Payne
-
Patent number: 4405493Abstract: Corrosion inhibiting particles comprise an inorganic oxide, particularly alumina, having corrosion inhibiting anions, particularly phosphate, chromate or benzoate anions, chemically bound to them. They may be prepared by contacting an oxide containing hydroxyl groups with an acidic solution containing the anions at ambient temperatures. The particles may be incorporated into protective coatings, e.g. paints based on epoxy resins, alkyd resins or chlorinated rubbers, in amounts up to 80% wt based on dry film weight, giving coatings with up to 4.0% corrosion inhibiting anions. Release of the anions is by ion-exchange with other anions e.g. the chloride anions of sea water or salt spray, and does not, as is normal with corrosion inhibiting coatings, depend on water solubility.Type: GrantFiled: January 15, 1980Date of Patent: September 20, 1983Assignee: The British Petroleum Company LimitedInventor: David A. Pippard
-
Patent number: 4404114Abstract: An aluminum corrosion inhibitor composition comprising an aqueous and/or alcohol solution of a polymerizable-acid graft copolymer plus at least one organic and/or inorganic silicate, together with a method for using such composition.Type: GrantFiled: June 17, 1982Date of Patent: September 13, 1983Assignee: Union Carbide CorporationInventors: Paul H. Mohr, William N. Matulewicz
-
Patent number: 4402847Abstract: Compositions and method of using said compositions for inhibiting mineral scale and the corrosion of high lead solder and the cavitation-erosion corrosion of aluminum in aqueous systems are disclosed. Unexpectedly, a mixture of a siloxane-silicate copolymer with an azole is effective in reducing the corrosion of high lead solder and aluminum, particularly the cavitation-erosion corrosion of aluminum in contact with aqueous liquids, such as aqueous alcohol solutions used as heat transfer media. Antifreeze concentrates and a process for inhibiting corrosion are also disclosed.Type: GrantFiled: May 19, 1982Date of Patent: September 6, 1983Assignee: BASF Wyandotte CorporationInventors: Joe C. Wilson, Stanley T. Hirozawa
-
Patent number: 4401587Abstract: A method of inhibiting corrosion of low carbon steel in an aqueous system comprising treating said system with 1.0 to 300 parts per million by weight of the total aqueous content of said system, of a composition comprising aminomethylphosphonic acid compounds and polymaleic anhydride or amine adducts thereof in a weight ratio of from 10:1 to 1:10.Type: GrantFiled: December 16, 1981Date of Patent: August 30, 1983Assignee: Calgon CorporationInventor: Bennett P. Boffardi