WO2000039359A1 - Compositions inhibitrices de corrosion et procedes de controle de la corrosion du metal dans des systemes de saumure - Google Patents

Compositions inhibitrices de corrosion et procedes de controle de la corrosion du metal dans des systemes de saumure Download PDF

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Publication number
WO2000039359A1
WO2000039359A1 PCT/US1999/030562 US9930562W WO0039359A1 WO 2000039359 A1 WO2000039359 A1 WO 2000039359A1 US 9930562 W US9930562 W US 9930562W WO 0039359 A1 WO0039359 A1 WO 0039359A1
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Prior art keywords
effective amount
blend
corrosion
hpa
group
Prior art date
Application number
PCT/US1999/030562
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English (en)
Inventor
Jasbir S. Gill
Susan P. Rey
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Calgon Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Calgon Corporation filed Critical Calgon Corporation
Priority to AU22059/00A priority Critical patent/AU2205900A/en
Publication of WO2000039359A1 publication Critical patent/WO2000039359A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
    • C23F11/10—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using organic inhibitors

Definitions

  • the present invention relates to methods of inhibiting the corrosion of metallic surfaces of water- carrying systems, and to compositions for use in such a method, particularly in which the water of the system is oxygen bearing. More particularly, the present invention relates to the use of compositions in the presence of sodium chloride and/or calcium chloride brine systems.
  • Oxygen corrosion is, of course, a serious problem in any metal-containing aqueous system.
  • the corrosion of iron and steel is of principal concern because of their extensive use in many types of industrial and municipal water systems.
  • corrosion of copper and copper containing metals is also of concern and many systems use a combination of metals.
  • Brines are used in various industrial applications. Of particular interest are the brines used in the cooling systems or chillers, as these are widely known. These systems are supposed to be closed loop but in practice due to leaks and operational requirements, they are practically oxygen saturated. These systems are, very aggressive for corrosion, and thus corrosion control is necessary.
  • Brine cooling systems such as calcium chloride, sodium chloride and lithium chloride brines
  • sodium chloride and lithium chloride brine systems being particularly aggressive towards carbon steel. If corrosion control is not used, piping and other components must be changed frequently.
  • chromate-based products were used to inhibit corrosion in these brine systems . Chromates are soluble in these concentrated solutions and provide good corrosion protection. Subsequently, it was determined that chromium-containing products are hazardous to the environment and their use is being discontinued.
  • a composition known as Belcor 575 is 2- hydroxyphosphono-acetic acid (HPA) , is disclosed and available from Ciba Geigy.
  • HPA 2- hydroxyphosphono-acetic acid
  • This product is a known corrosion inhibitor as disclosed in U.S. Patent No. 5,068,059.
  • This product, HPA is also known as a corrosion inhibitor in brines as disclosed in U.S. Patent Nos. 4,606,890 (Example 25) and 5,292,455, the disclosures of which are incorporated herein by reference in their entirety.
  • PBTC 2-phosphonobutane-l, 2 , 4 tricarboxylic acid
  • Phosphonocarboxylic acid is also known and is specifically phosphonate [ ( acrylic acid ) x ( AMPS) y ] n copolymer, such as Belclene 494 (AMPS is 2 acrylamido-2- methylpropyl sulfonic acid) .
  • AMPS is 2 acrylamido-2- methylpropyl sulfonic acid
  • Bricorr 288 a polycarboxylic acid with a phosponate end cap that is a homopolymer (POCA homopolymer) .
  • Azoles are also known corrosion inhibitors, such as the mercapto benzotriazoles (MBT) , benzotriazoles (BT) , tolyltriazoles, and mixtures thereof.
  • MBT mercapto benzotriazoles
  • BT benzotriazoles
  • tolyltriazoles and mixtures thereof.
  • Specific tolyltriazoles are the hydrogenated tolyltriazoles (e.g. Cobratec 928) and sodium tolyltriazoles (NaTT) .
  • a blend composition useful to inhibit the corrosion of metal surfaces that comprises; a) an effective amount of 2-phosphonobutane-l, 2, 4 tricarboxylic acid (PBTC) and b) an effective amount of hydroxyphosphono-acetic acid (HPA) .
  • PBTC 2-phosphonobutane-l, 2, 4 tricarboxylic acid
  • HPA hydroxyphosphono-acetic acid
  • a blend composition useful to inhibit the corrosion of metal surfaces that comprises; a) an effective amount of a phosphono carboxylic acid homopolymer (POCA homopolymer) and b) an effective amount of a compound selected from the group consisting of 2- phosphonobutane-1, 2, 4 tricarboxylic acid (PBTC), hydroxyphosphono-acetic acid (HPA), and mixtures thereof.
  • POCA homopolymer phosphono carboxylic acid homopolymer
  • PBTC 2- phosphonobutane-1, 2, 4 tricarboxylic acid
  • HPA hydroxyphosphono-acetic acid
  • a blend composition useful to inhibit the corrosion of metal surfaces that comprises; a) an effective amount of a phosponocarboxylic acid copolymer (POCA copolymer) and b) an effective amount of hydroxyphosphono-acetic acid (HPA) .
  • POCA copolymer phosponocarboxylic acid copolymer
  • HPA hydroxyphosphono-acetic acid
  • compositions are also useful -in the process of corrosion inhibition in various brine systems, such as sodium chloride, lithium chloride, and calcium chloride brine systems .
  • Another aspect of the present invention for use in non-calcium chloride brine systems comprises a corrosion inhibitor and a small amount of calcium ions (preferably about 40ppm or more as calcium chloride) , optionally in the presence of an azole.
  • the corrosion inhibitor is selected from the group consisting of PBTC, HPA, PAPEMP (polyamino polyether methylenephosphonate i.e. TRC-289) , POCA homopolymer, and POCA copolymer.
  • the small amount of calcium ions added to the system helps the corrosion inhibitor function as a corrosion inhibitor.
  • it is combined with an amount of calcium ions to provide enhanced corrosion inhibition in the brine system.
  • blend compositions that are very useful in the inhibition of corrosion of metal surfaces. These blend compositions are particularly useful in the metal corrosion inhibition of brine systems, such as sodium chloride and calcium chloride brine systems. The inventors have unexpectedly discovered very useful replacements of chromates in brine systems .
  • each of the above inhibitors by themselves, provide improved corrosion inhibition to non-calcium chloride brine systems when a small amount of calcium ions is added to the system (about 40ppm or more) .
  • a small amount of calcium ions is added to the system (about 40ppm or more) .
  • brine systems e.g. sodium chloride and lithium chloride brine systems
  • a third component is added, either TTNa or Cobratec 928.
  • the calcium ions are preferably added in the form of calcium chloride.
  • the amount of calcium ions added or present in these systems is generally at least about 40ppm, preferably about 50 to lOOOppm, more preferably about 50 to 600ppm, with an amount of about 100 to about 300ppm calcium ions being most preferred.
  • composition according to the present invention has a synergistic effect upon the prevention of corrosion of metal surfaces when an effective amount of both a) and b) are present in the system to be treated, even at very low levels.
  • This amount is preferably at least about lOOppm of the total corrosion inhibitors. Amounts of all corrosion inhibiting compounds can be much higher than this, depending upon desired corrosion prevention levels. However, due to costs and small incremental corrosion prevention, amounts much above lOOOppm are somewhat less preferred.
  • the weight ratio of a) to b) in each of the blends can vary significantly, so long as both a) and b) are present.
  • this weight ratio of a) to b) preferably varies from about 1:10 to 10:1, more preferably at a weight ratio of about 40 to about 60 wt . % a) and about 40 to about 60 wt . % b) , with a ratio of a) to b) of about 50/50 being most preferred.
  • the POCA homopolymer of a) is preferably a polycarboxylic acid with a phosponate end cap, more preferably a low molecular weight polymaleic acid, with Bricorr-288 being most preferred.
  • component b) can be a blend of PBTC and HPA
  • component b) is preferably a blend of PBTC and HPA and preferably in a weight ratio of PBTC to HPA that varies from 1:10 to 10:1.
  • the POCA copolymer is preferably a low molecular weight phosphonate [ ( acrylic acid ) x ( AMPS) y ] n copolymer, such as Belclene 494 (AMPS is 2 acrylamido-2- methylpropyl sulfonic acid) .
  • AMPS is 2 acrylamido-2- methylpropyl sulfonic acid
  • x is preferably about 70 to about 90 wt . % of the monomer units
  • y is preferably about 10 to about 30 wt . % of the monomer units
  • n is an integer between 2 and 50 (more preferably 4 to 20) .
  • composition according to the present invention preferably contains an azole c) , in additional to the components a) and b) .
  • the azole of the composition according to the present invention is preferably selected from the group consisting of mercapto benzotriazoles
  • MBT benzotriazoles
  • BT benzotriazoles
  • tolyltriazoles and mixtures thereof, wherein said tolyltriazoles are preferably selected from the group consisting of hydrogenated tolyltriazoles (Cobratec 928), sodium tolyltriazoles (NaTT) , and mixtures thereof.
  • the amount of the azole c) in said blend is preferably present in a concentration of about 1 to about 90 percent by weight.
  • the amount of component a) is preferably in a concentration of about 5 to about 90 wt . %, more preferably about 10 to about 89 wt . %, with an amount of about 40 to about 58 wt. % being most preferred.
  • component b) is also preferably in a concentration of about 5 to about 90 wt . %, more preferably about 10 to about 89 wt. %, with an amount of about 40 to about 58 wt. % being most preferred.
  • the azole c) is preferably present in the composition, and in an effective amount. This amount is preferably about 1 to about 20 wt .
  • the weight percent of all three components of the blend with respect to each other are preferably present in a concentration of about 10 to about 89 wt. % a), about 10 to about 89 wt . % b) , and about 1 to about 20 wt. % of an azole c) .
  • This relative concentration is more preferably about 40 to about 58 wt . % a), about 40 to about 58 wt. % b) , and about 2 to about 10 wt. % of an azole c) .
  • composition according to the present invention is preferably in a brine in a sufficient amount to inhibit the corrosion of the metal in contact with said brine.
  • This composition is preferably added as a concentrate in a concentration in water and then diluted when added to the system and preferably contains less than 50 wt. % solids, more preferably about 42 wt. % solids.
  • composition according to the present invention is preferably present in an aqueous system in a concentration of about 100 to 1000 ppm by weight. In calcium chloride brines this amount is more preferably about 100 to about 500 ppm, with about 150 to about 300 ppm being most preferred.
  • concentration of the components present in said aqueous system preferably ranges, with respect to each other from about 10 to about 500 ppm a) , about 10 to about 500 ppm b) , and about 1 to about 50 ppm of an azole c) .
  • This concentration of components is more preferably about 20 to about 300 ppm a) , about 20 to about 300 ppm b) , and about 5 to about 30 ppm of an azole; with about 50 to about 200 ppm a) , about 50 to about 200 ppm b) , and about 10 to about 20 ppm of an azole being most preferred.
  • the composition according to the present invention is a synergistic blend of a) and b) , and optional c) .
  • the components a) , b) and optional c) of the blend are each present in an aqueous system in a concentration in an amount that results in a synergistic combination such that the corrosion inhibition of a certain concentration of each component, when added together does not equal the actual corrosion inhibition of the equivalent blend of a) and b) .
  • the above compositions are also useful in the process of corrosion inhibition in various brine systems, such as sodium chloride, lithium chloride, and calcium chloride brine systems.
  • the method of inhibiting the corrosion of metal surfaces according to the present invention comprises; contacting said metal surfaces with an aqueous solution of a blend selected from the group consisting of:
  • PBTC 2-phosphonobutane- 1,2,4 tricarboxylic acid
  • HPA hydroxyphosphono-acetic acid
  • POCA homopolymer an effective amount of a phosphonocarboxylic acid homopolymer
  • HPA an effective amount of a compound selected from the group consisting of (PBTC), (HPA), and mixtures thereof; and
  • POCA copolymer phosponocarboxylic acid copolymer
  • HPA phosponocarboxylic acid copolymer
  • the method according to the present invention entails the inhibition of corrosion on metal surfaces, generally a combination of different metals.
  • These above compositions are multi-metal corrosion inhibitors and can protect systems made up of a combination of metals.
  • These metal surfaces that are contacted with the blend of a) and b) are preferably made of iron, copper, aluminum and their alloys, such as steel, brass, copper, and combinations thereof. Mild steel and high carbon steel are the most preferred due to significant corrosion inhibition of this metal with preferred blends.
  • the following examples are intended to illustrate the present invention but should not be considered as a limitation on the reasonable scope thereof.
  • Each closed system corrosion study was performed by immersing a rack of five 1.0 inch by 2.0 inch coupons of varying metallurgies in a glass reaction kettle containing 3.0 L of treated deionized water, and then blanketing the treated deionized water with saturated C0 2 scrubbed air. The air was fed through a gas sparge tube and an outlet tube was provided to enable a positive pressure of air for oxygen saturation.
  • An Orbisphere Model 26060 Oxygen Analyzer with Sensor 2110 was used to measure the oxygen concentration.
  • the kettles were nestled in a heating mantle connected to a variac.
  • the variac was set to control the temperatures at 65.6° +/- 5°C .
  • the pH was periodically measured, but not controlled.
  • the coupons were precleaned as outlined in CPT-203- CW, "Methods of Cleaning and Polishing Specimens Before Testing" and then weighed on a five place analytical balance. Next they were placed in an ASTM D1384 corrosion test rack in the following order by metallurgy: carbon steel, stainless steel, 90/20 Cu/Ni, Admiralty brass, and copper. Teflon spacers (3/16 inch) were placed between coupons, and between end coupons and the brass legs. The center screw was covered with a Teflon insulating sleeve, before the coupons were slipped over it.
  • test conditions were: 65°C+/-5°C pH 8.0 25% CaCl 2 Test Solution

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)

Abstract

L'invention concerne des compositions et des procédés permettant d'inhiber la corrosion des surfaces métalliques. Ces dernières comprennent au moins un mélange sélectionné dans le groupe se composant de (I) (a) une quantité efficace de PBTC et (b) une quantité efficace de HPA; (II) (a) une quantité efficace d'un homopolymère de POCA et (b) une quantité efficace d'un composé sélectionné dans le groupe se composant de PBTC, HPA et des mélanges de ces derniers et (III) (a) une quantité efficace d'un copolymère de POCA et (b) une quantité efficace de HPA. Chacun des mélanges peut contenir éventuellement un azole (c).
PCT/US1999/030562 1998-12-29 1999-12-21 Compositions inhibitrices de corrosion et procedes de controle de la corrosion du metal dans des systemes de saumure WO2000039359A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU22059/00A AU2205900A (en) 1998-12-29 1999-12-21 Corrosion inhibitor compositions and methods to control metal corrosion in brinesystems

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US11408798P 1998-12-29 1998-12-29
US11409398P 1998-12-29 1998-12-29
US11409498P 1998-12-29 1998-12-29
US60/114,094 1998-12-29
US60/114,093 1998-12-29
US60/114,087 1998-12-29

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WO2000039359A1 true WO2000039359A1 (fr) 2000-07-06

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2995900A1 (fr) * 2012-09-27 2014-03-28 Chryso Copolymeres a groupements gem-acetophosphones
WO2016092010A1 (fr) 2014-12-11 2016-06-16 Clariant International Ltd Composition inhibitrice liquide, son procédé de préparation et son utilisation dans le cadre de la lutte contre la corrosion par la saumure lourde
US10519360B2 (en) 2014-12-11 2019-12-31 Clariant International Ltd. Liquid inhibitor composition and a method for its preparation and application as a heavy brine corrosion control
US10611951B2 (en) 2014-12-11 2020-04-07 Clariant International Ltd. Liquid inhibitor composition and a method for its preparation and application as a heavy brine corrosion control

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53146942A (en) * 1977-05-30 1978-12-21 Nitto Chem Ind Co Ltd Corrosion inhibitor for circulating cooling water or brine
GB2118159A (en) * 1982-04-20 1983-10-26 Dearborn Chemicals Ltd The treatment of aqueous systems
DE3620018A1 (de) * 1985-06-14 1986-12-18 Drew Chemical Corp., Boonton, N.J. Korrossionsinhibitor
EP0215670A2 (fr) * 1985-09-16 1987-03-25 W.R. Grace & Co.-Conn. Composition anticorrosion
EP0225051A1 (fr) * 1985-10-29 1987-06-10 W.R. Grace & Co.-Conn. Traitement de systèmes aqueux
US4798675A (en) * 1987-10-19 1989-01-17 The Mogul Corporation Corrosion inhibiting compositions containing carboxylated phosphonic acids and sequestrants
EP0541318A1 (fr) * 1991-11-06 1993-05-12 Diversey Corporation Composition et méthode de traitement des eaux de refroidissement
US5292455A (en) * 1993-02-25 1994-03-08 Betz Laboratories, Inc. Corrosion inhibition of calcium chloride brine
WO1996011291A1 (fr) * 1994-10-11 1996-04-18 Fmc Corporation (Uk) Limited Compositions inhibant la corrosion
EP0831065A1 (fr) * 1996-09-24 1998-03-25 Calgon Corporation Un procédé pour contrÔler le tartre dans un système aqueux en utilisant une composition synergique

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53146942A (en) * 1977-05-30 1978-12-21 Nitto Chem Ind Co Ltd Corrosion inhibitor for circulating cooling water or brine
GB2118159A (en) * 1982-04-20 1983-10-26 Dearborn Chemicals Ltd The treatment of aqueous systems
DE3620018A1 (de) * 1985-06-14 1986-12-18 Drew Chemical Corp., Boonton, N.J. Korrossionsinhibitor
EP0215670A2 (fr) * 1985-09-16 1987-03-25 W.R. Grace & Co.-Conn. Composition anticorrosion
EP0225051A1 (fr) * 1985-10-29 1987-06-10 W.R. Grace & Co.-Conn. Traitement de systèmes aqueux
US4798675A (en) * 1987-10-19 1989-01-17 The Mogul Corporation Corrosion inhibiting compositions containing carboxylated phosphonic acids and sequestrants
EP0541318A1 (fr) * 1991-11-06 1993-05-12 Diversey Corporation Composition et méthode de traitement des eaux de refroidissement
US5292455A (en) * 1993-02-25 1994-03-08 Betz Laboratories, Inc. Corrosion inhibition of calcium chloride brine
WO1996011291A1 (fr) * 1994-10-11 1996-04-18 Fmc Corporation (Uk) Limited Compositions inhibant la corrosion
EP0831065A1 (fr) * 1996-09-24 1998-03-25 Calgon Corporation Un procédé pour contrÔler le tartre dans un système aqueux en utilisant une composition synergique

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 003, no. 023 (C - 038) 26 February 1979 (1979-02-26) *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2995900A1 (fr) * 2012-09-27 2014-03-28 Chryso Copolymeres a groupements gem-acetophosphones
WO2014049037A1 (fr) * 2012-09-27 2014-04-03 Chryso Copolymères à groupements gem-acétophosphonés
US9371424B2 (en) 2012-09-27 2016-06-21 Chryso Copolymers having gem-acetophone groups
WO2016092010A1 (fr) 2014-12-11 2016-06-16 Clariant International Ltd Composition inhibitrice liquide, son procédé de préparation et son utilisation dans le cadre de la lutte contre la corrosion par la saumure lourde
WO2016092011A1 (fr) 2014-12-11 2016-06-16 Clariant International Ltd Composition inhibitrice liquide, son procédé de préparation et son utilisation dans le cadre de la lutte contre la corrosion par la saumure lourde
US10519360B2 (en) 2014-12-11 2019-12-31 Clariant International Ltd. Liquid inhibitor composition and a method for its preparation and application as a heavy brine corrosion control
US10611951B2 (en) 2014-12-11 2020-04-07 Clariant International Ltd. Liquid inhibitor composition and a method for its preparation and application as a heavy brine corrosion control

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