Classifications

• • 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
  • C23F11/04—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in markedly acid liquids
• • 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
  • C23F11/14—Nitrogen-containing compounds
  • C23F11/147—Nitrogen-containing compounds containing a nitrogen-to-oxygen bond
• • 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
  • C23F11/18—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 inorganic inhibitors
  • C23F11/181—Nitrogen containing compounds
• • 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
  • C23F11/18—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 inorganic inhibitors
  • C23F11/182—Sulfur, boron or silicon containing compounds
• • 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
  • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
  • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
  • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
  • C23G1/04—Cleaning or pickling metallic material with solutions or molten salts with acid solutions using inhibitors
• • 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
  • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
  • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
  • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
  • C23G1/08—Iron or steel
  • C23G1/088—Iron or steel solutions containing organic acids

Definitions

• the present invention relates to the field of corrosion, by sulfonic acids, passivable metals and alloys, especially based on iron, nickel, titanium, copper, aluminum, molybdenum, manganese, lead, and their alloys, and that couples of these metals or alloys obtained by contact (crimping, riveting, bolting, welding, brazing).
• the invention more particularly relates to the protection of said metals against corrosion by sulfonic acids, including organosulfonic acids.
• Sulfonic acids more specifically organo-sulphonic acids, and in particular methanesulphonic acid (AMS), para-toluenesulphonic acid (APTS), benzenesulphonic acid (BS), trifluoromethanesulphonic acid are strong acids widely used in many applications, including catalysis and surface treatment (electroplating, stripping, cleaning, descaling, and others).
• AMS methanesulphonic acid
• APTS para-toluenesulphonic acid
• BS benzenesulphonic acid
• trifluoromethanesulphonic acid are strong acids widely used in many applications, including catalysis and surface treatment (electroplating, stripping, cleaning, descaling, and others).
• EP-A-0 931 654 it has also been disclosed, in EP-A-0 931 654, that it is possible to inhibit the corrosion of stainless steels in an organosulfonic medium, by adding at least one oxidant chosen from the salts or oxides of cerium (IV), iron (III), molybdenum (VI) or vanadium (V), nitrites and persulfates.
• oxidant chosen from the salts or oxides of cerium (IV), iron (III), molybdenum (VI) or vanadium (V), nitrites and persulfates.
• B. Gaur and HS Srinivasan (British Corrosion Journal, 34 (1), (1999), 63-66) have shown that the addition of ferric or nitrate ions can produce a corrosion inhibiting effect by AMS on various steels.
• Some applications in particular stripping, descaling, use solutions based on AMS formulated with the addition of other products such as surfactants or complexing metal ions (sulfamic acid, citric, oxalic). These latter can cancel the inhibitory effect of oxidizing metal salts or lead to high doses of inhibitors, not compatible with respect for the environment.
• the present invention relates to the use of at least one compound of general formula (1):
• X is selected from:
• alkyl radical R linear or branched, comprising from 1 to 6 carbon atoms
• An aryl radical Ar optionally substituted, in particular with at least one alkyl radical R;
• a radical -SO 2 -G where G represents H, OH, R, OR, OM, Ar, OAr, NH 2 , NHR and NRR ', where R and Ar are as defined previously, R' represents an alkyl radical; , linear or branched, comprising from 1 to 6 carbon atoms, and M represents a mono- or bi-valent metal cation, preferably a cation of an alkali metal or alkaline earth metal; and
• the compound of formula (1) is nitrous acid.
• the compound of formula (1) is nitrous anhydride.
• X represents -SO 2 -G, and more preferably -SO 2 -G where -G represents -OH, in which case the corrosion inhibitor is nitrosyl acid sulfate ( SHN, CAS No. 7782-78-7).
• X represents SO2-G, where G represents an alkyl radical R, preferably the methyl radical, in which case the corrosion inhibitor (CAS No. 1 17933-98-9) is the reaction product of methanesulfonic acid (or its chloride) with nitrous acid.
• X is chosen from:
• alkyl radical R linear or branched, comprising from 1 to 6 carbon atoms
• An aryl radical Ar optionally substituted, in particular with at least one alkyl radical R;
• a radical -SO 2 -G where G represents H, OH, R, OR, OM, Ar, OAr, NH 2 , NHR and NRR ', where R and Ar are as defined previously, R' represents an alkyl radical; , linear or branched, comprising from 1 to 6 carbon atoms, and M represents a mono- or bi-valent metal cation, preferably a cation of an alkali metal or alkaline earth metal; and
• the SHN which is therefore known to be an impurity inherent in the preparation of sulfuric acid, is, in pure form, a very hygroscopic solid, unstable, reacting violently with water and producing toxic fumes (NO x ) in the presence of moisture.
• corrosion inhibitors are specific to an acid.
• the corrosion inhibitors described in the literature and effective for the protection of stainless steels in sulfuric acid are ineffective for phosphoric acid and increase the rate of corrosion in hydrochloric acid.
• corrosion inhibitors with hydrochloric acid are totally unsuitable for sulfuric acid.
• the research work of the present inventors has made it possible to discover that certain nitrosyl derivatives have an activity inhibiting corrosion of metals. by sulphonic acids, and more particularly by organo-sulphonic acids.
• the metals in question are more specifically steels, and in particular common stainless steels (for example of the AISI 304L and AISI 316L type), but also more generally any stainless steel as defined in standard NF EN 10088-1.
• the subject of the invention is a composition
• a composition comprising at least one compound of formula (1) as defined above, and at least one sulphonic acid, as defined above, preferably at least one acid.
• organosulfonic preferably at least one alkanesulfonic acid, more preferably AMS.
• effective amount is meant an amount of compound (s) of formula (1) between 1 ppm and a few percent, for example 10%, preferably between 5 ppm and 1000 ppm, more preferably between 10 ppm and 800 ppm, by weight relative to the total weight of the composition.
• the present invention also relates to a method for protecting metals against corrosion by sulphonic acids, in particular passivable metals and alloys, in particular those based on iron, nickel, titanium, copper, aluminum, molybdenum, manganese, lead, and their alloys, as well as the torques (in the galvanic sense) of these metals or alloys of these metals or alloys obtained by contact (crimping, riveting, bolting, welding, brazing), characterized in that the sulphonic acid in contact with said metals is a composition as defined above comprising at least one compound of formula (1) as defined above.
• Said compounds of formula (1) are either commercially available or, when they are unstable, prepared according to known procedures or operating procedures available in the scientific literature, the patent literature or on the internet. When they are unstable, the compounds of formula (1) are advantageously prepared immediately before being added to the sulfonic acid, or the composition containing it.
• the acidic nitrosyl sulfate may be obtained according to various methods known to those skilled in the art, including the bubbling of a stoichiometric mixture of nitric oxide (NO) and carbon dioxide. nitrogen (NO2) in oleum (H 2 SO 4 mixture, SO3).
• NO2 nitric oxide
• oleum H 2 SO 4 mixture, SO3
• the thus obtained SHN in solution in the oleum can then be directly added to the sulfonic acid, or the composition containing it.
• at least one compound of formula (1) may be added in at least one sulphonic acid, which it is desired to limit, or even prevent, the corrosive effect on metals, according to any method known per se, by simple addition , and possible mixing.
• the compound of formula (1) can be generated in situ by adding a precursor of the compound of formula (1) which, in contact with the sulphonic acid or acids, is converted into said compound of formula ( 1).
• the compound O N-OSO 2 CH 3 (CAS Reg 1. 17933-98-9) can be prepared by adding a nitrogen oxide / nitrogen dioxide mixture to the methanesulfonic acid.
• sulfonic acid is preferably used to mean acids of formula R-SO 3 H, where R represents a linear or branched saturated hydrocarbon-based chain containing from 1 to 4 carbon atoms, or an aryl radical optionally substituted with a saturated hydrocarbon chain, linear or branched, containing from 1 to 4 carbon atoms, and optionally substituted, in whole or in part, with one or more halogen atoms, which are identical or different.
• the saturated hydrocarbon chain linear or branched, having 1 to 4 carbon atoms may be substituted, in whole or in part, with one or more halogen atoms selected from fluorine, chlorine and bromine, and in particular, the hydrocarbon chain which can be perhalogenated, more particularly perfluorinated.
• aryl is meant an aromatic radical, preferably phenyl or naphthyl, more preferably phenyl.
• the sulphonic acids included in the context of the present invention are organosulfonic acids preferably selected from methanesulfonic acid, ethanesulfonic acid, n -propane-sulphonic acid / 'n-propane-sulfonic acid, n-butane-sulfonic acid, /' n-butane-sulfonic acid, sec-butane-sulphonic acid, acid terf- butanesulfonic acid, trifluoromethanesulfonic acid, para-toluenesulfonic acid, benzenesulphonic acid and mixtures of two or more of them in all proportions.
• the sulphonic acid used in the context of the present invention is methanesulfonic acid, ethanesulfonic acid, trifluoromethanesulphonic acid or para-toluenesulphonic acid.
• the sulphonic acid used is methanesulfonic acid.
• the compositions according to the present invention comprising at least one sulphonic acid and an effective amount of at least one corrosion inhibitor of formula (1) are acidic compositions that can be used in any field where said sulphonic acids are usually used.
• the acidic compositions according to the invention have the advantage of being less corrosive, or even non-corrosive, with respect to the same acidic compositions that do not comprise a corrosion inhibitor (s).
• compositions according to the present invention may be of any type, liquid, in aqueous solutions more or less dilute, or in the form of gels or foaming gels, whose viscosities may vary in large proportions.
• compositions according to the present invention are used in pure form or diluted using various components, as indicated below.
• compositions comprise from 0.01% to 100% by weight of sulfonic acid (s) in combination with at least one corrosion inhibitor of formula (1) defined above, more generally of From 0.05% to 90% by weight, in particular from 0.5% to 75% by weight, relative to the total weight of said composition, the remainder of the composition comprising a solvent and / or a diluent, preferably a solvent and / or aqueous diluent, more preferably water, and optionally one or more additives, as defined later in the present description.
• sulfonic acid s
• at least one corrosion inhibitor of formula (1) defined above more generally of From 0.05% to 90% by weight, in particular from 0.5% to 75% by weight, relative to the total weight of said composition, the remainder of the composition comprising a solvent and / or a diluent, preferably a solvent and / or aqueous diluent, more preferably water, and optionally one or more additives, as defined later in the present description.
• the composition of the present invention comprises methanesulfonic acid, nitrosyl acid sulphate and water.
• compositions according to the present invention may optionally comprise one or more additives or auxiliaries commonly used in the field concerned and according to the intended applications.
• additives and auxiliaries include, without limitation, viscosity modifiers, rheology, foaming agents, anti-foaming, surfactants, and others, disinfectants, biocides, stabilizers, oxidizing agents , enzymes, pigments, dyes, flame retardants, flame retardant, and others.
• compositions according to the invention may thus comprise one or more additives, such as those chosen from:
• Solvents for example alcohols, esters, ketones, amides, and others;
• biocides • biocides, disinfectants (bromoacetic acid, peracetic acid, hydrogen peroxide, chlorine dioxide, chlorine, bromine, and others);
• Organic or mineral acids eg sulfuric, phosphoric, nitric, sulfamic, acetic, citric, acetic, ascorbic, formic, lactic, glycolic, oxalic and others;
• Anionic, cationic, nonionic or amphoteric surfactants such as ethoxylated alcohols and / or amines, alkyl and / or aryl sulfonates), emulsifiers, detergents, soaps, and the like; • foaming agents, antifoam agents;
• Anti-gels for example ethylene glycol, propylene glycol, and others
• complexing agents for metals, for example organic complexing agents, such as ethylenediaminetetraacetic acid (EDTA) or diethylenetriamine pentaacetic acid.
• organic complexing agents such as ethylenediaminetetraacetic acid (EDTA) or diethylenetriamine pentaacetic acid.
• EDTA ethylenediaminetetraacetic acid
• DTPA acetic acid
• HEDTA (2-hydroxyethyl) ethylenediaminetriacetic acid
• MGDA methylglycinediacetic acid
• NDA nitrilotriacetic acid
• the compositions may comprise one or more other acids, organic or inorganic, among which may be mentioned, by way of non-limiting examples, phosphoric acid, sulfuric acid, nitric acid, carboxylic acids such as sulfamic acid, citric acid, oxalic acid, glycolic acid, acetic acid, ascorbic acid, formic acid, lactic acid and mixtures of two or more of them in all proportions.
• phosphoric acid sulfuric acid
• nitric acid carboxylic acids
• carboxylic acids such as sulfamic acid, citric acid, oxalic acid, glycolic acid, acetic acid, ascorbic acid, formic acid, lactic acid and mixtures of two or more of them in all proportions.
• solubilizing or hydrotropic agents that can be used in the formulations according to the invention, mention may be made, by way of example and in a nonlimiting manner, of sodium xylene- or cumene-sulfonates. Such agents are however not essential in the compositions of the invention.
• compositions of the invention may vary in large proportions and will be easily adjusted by the skilled person according to the specific applications envisaged.
• compositions according to the present invention are in the form of an aqueous, organic or even hydro-organic formulation, which can be prepared in the form of a concentrated, concentrated mixture which can be diluted with water by final user.
• the formulation may also be a ready-to-use formulation, i.e., it does not need to be diluted.
• compositions of the present invention may be formulated as gels or foaming gels.
• the use of at least one ethoxylated amine oxide such as, without limitation, Cecajel ® OX100 from CECA, or "Aromox ® T12 from Akzo alone or combination with at least one oxide of dimethylalkylamine helps provide stability to the gel, in particular foaming gel.
• An aqueous, organic or hydro-organic formulation in the form of a solution, a gel or in the form of a foaming gel, which is particularly preferred, is a formulation comprising from 0.01% to 97%, preferably of 0.05%. at 75%, more preferably from 0.5% to 70% by weight of methanesulfonic acid, combined with at least one compound of formula (1) as defined above.
• the formulation may be prepared in the form of a concentrate, and with an appropriate viscosity, and then diluted before use until the expected efficiency is obtained, as regards the viscosity and possibly the power. foaming.
• compositions of the present invention may for example be prepared from commercial acid solutions, and by way of non-limiting examples from methanesulfonic acid in aqueous solution sold by Arkema under the name Scaleva ® or also under the name Lutropur ® sold by BASF, ready for use or diluted with water in the proportions indicated above.
• compositions comprising at least one sulphonic acid and at least one corrosion inhibitor of formula (1) as defined above further comprise a disinfectant, in particular chlorine dioxide.
• the chlorine dioxide can be generated in situ by adding sodium chlorite to the composition of the invention.
• compositions according to the present invention further comprising a disinfecting agent as indicated above find particularly interesting applications for cleaning and disinfection of cooling water circuits, disinfection of sanitary water and to disinfect the equipment. hospital.
• the compositions according to the invention find a particularly advantageous use in the storage of sulfonic acids, or solutions, in particular aqueous solutions of sulfonic acids.
• the presence, in said compositions of the present invention, of at least one corrosion inhibiting agent makes it possible to dispense with plastic coating films, which are generally used for storing said acids in metal tanks, especially in stainless steel tanks.
• compositions according to the present invention are their very good storage stability, as well as their very good temperature stability.
• the compositions of the invention which can be used in many fields of application, can in particular be used in chemical reactions, requiring the use of sulfonic acids and conducted in metal reactors, at temperatures for example between -10 ° C and 200 ° C.
• compositions according to the present invention find applications in all fields where acidic compositions are required, in particular aqueous acidic solutions coming into contact with the metals mentioned above and whose corrosion is desired to be limited or avoided.
• Such fields of application are, for example and without limitation, storage, catalytic reactions (such as esterification reactions in acid catalysis), cleaning, descaling, detergency, pickling, electroplating, surfacing ("plating" in English, especially in the electronic field), and others.
• the fields of application are stripping, cleaning, descaling and deterging of mineral and / or organic stains in the food industry, such as dairies, cheese factories, packaging. raw and meat products, breweries, as well as stripping, cleaning, and descaling of mineral residues, in cement plants, in all areas where it is necessary and desirable to eliminate rust, or in oil and gas operations where acid solutions are required for the dissolution of underground rocks, especially carbonate rocks.
• compositions according to the present invention are all the fields in which at least one sulphonic acid is stored or conveyed. in containers, drums, tanks, vessels, reactors, fermenters, pipes, pipes, tubes, valves, which may be corroded and whose corrosion is to be limited or avoided.
• the present invention relates to the use of a composition comprising at least one sulphonic acid and at least one corrosion inhibitor of said (or said) sulphonic acid (s) as defined above for the storage of said acids, catalytic reactions or cleaning, descaling, detergency, pickling, disinfection, electroplating, surfacing, catalytic reactions, and the like, at temperatures ranging from -10 ° C to 200 ° C preferably from 0 ° C to 160 ° C.
• compositions according to the present invention may be applied according to any method known to those skilled in the art, and in particular under pressure, or still using a spray gun.
• the sulphonic acid comprising the corrosion inhibitor defined above is advantageously used in the form of a formulation, for example an aqueous, organic or hydro-organic formulation, in liquid form, of gel or foaming gel, as defined above.
• the electrochemistry test is carried out using a conventional 3 electrode assembly (reference electrode (saturated calomel electrode ECS), working electrode made in the material to be studied and platinum counter-electrode. ) connected to a BIOLOGIC VMP3 or EGG 273A potentiostat.
• test piece of the material to be tested is polished with sandpaper P1000, in order to have a reproducible initial state, and then left in the open air for at least 24 hours.
• the working electrode is installed on a rotating system which sets the rotational speed: the speed of rotation is set at 1000 revolutions per minute.
• a 316L stainless steel test specimen, measuring 35 x 23 x 3 mm, is in standard condition (polished P320 and passivated in air for at least 24 hours).
• 70% AMS Scaleva ®, Arkema
• the acidic nitrosyl sulfate used here is a 60% by weight solution in sulfuric acid prepared by bubbling a stoichiometric mixture 1/1 nitric oxide (NO) and nitrogen dioxide (NO2) (70 g and 1 10 g respectively) in 830 g of oleum (mixture H 2 SO / SO 3 : 77/23 by weight).
• the steel specimen After 21 days, the steel specimen is always passivated, indicating a lack of corrosion, even after this period of time.
• This test consists of a monitoring of the corrosion potential as a function of time:
• the temperature of the medium is gradually increased in increments of 10 ° C: after 5 days, the medium is at 90 ° C: 316L stainless steel is always passive.

Landscapes

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

Applications Claiming Priority (2)

Publications (1)

Family

ID=60627767

Family Applications (1)

Country Status (9)

Families Citing this family (8)

Family Cites Families (16)

• 2017
  • 2017-09-01 FR FR1758100A patent/FR3070694B1/fr active Active
• 2018
  • 2018-08-30 KR KR1020207005830A patent/KR102658514B1/ko active Active
  • 2018-08-30 WO PCT/FR2018/052128 patent/WO2019043340A1/fr not_active Ceased
  • 2018-08-30 US US16/643,098 patent/US11788192B2/en active Active
  • 2018-08-30 CN CN201880056283.8A patent/CN111032918A/zh active Pending
  • 2018-08-30 EP EP18773239.1A patent/EP3676423A1/de active Pending
  • 2018-08-30 MY MYPI2020000991A patent/MY210240A/en unknown
  • 2018-08-31 TW TW107130654A patent/TWI685588B/zh active
• 2020
  • 2020-02-11 PH PH12020500310A patent/PH12020500310A1/en unknown

Also Published As

Similar Documents

Legal Events