EP2470689A1 - Beizverfahren für edelstahl - Google Patents
Beizverfahren für edelstahlInfo
- Publication number
- EP2470689A1 EP2470689A1 EP10745563A EP10745563A EP2470689A1 EP 2470689 A1 EP2470689 A1 EP 2470689A1 EP 10745563 A EP10745563 A EP 10745563A EP 10745563 A EP10745563 A EP 10745563A EP 2470689 A1 EP2470689 A1 EP 2470689A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pickling
- hydrofluoric acid
- concentration
- hydrogen peroxide
- rinsing
- Prior art date
- Legal status (The legal status 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 status listed.)
- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims abstract description 70
- 238000005554 pickling Methods 0.000 title claims abstract description 61
- 229910000831 Steel Inorganic materials 0.000 title description 6
- 239000010959 steel Substances 0.000 title description 6
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims abstract description 63
- 230000004913 activation Effects 0.000 claims abstract description 11
- 238000002203 pretreatment Methods 0.000 claims abstract description 3
- 238000004381 surface treatment Methods 0.000 claims abstract description 3
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 32
- 239000003381 stabilizer Substances 0.000 claims description 18
- 239000002253 acid Substances 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 13
- 229910001220 stainless steel Inorganic materials 0.000 claims description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 239000010935 stainless steel Substances 0.000 claims description 12
- 239000000243 solution Substances 0.000 claims description 6
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 4
- 239000000706 filtrate Substances 0.000 claims description 4
- 150000002222 fluorine compounds Chemical class 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims description 2
- 230000003472 neutralizing effect Effects 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 239000012141 concentrate Substances 0.000 claims 1
- 229910021645 metal ion Inorganic materials 0.000 claims 1
- 229910000851 Alloy steel Inorganic materials 0.000 abstract 1
- 239000000203 mixture Substances 0.000 description 10
- QPJSUIGXIBEQAC-UHFFFAOYSA-N n-(2,4-dichloro-5-propan-2-yloxyphenyl)acetamide Chemical compound CC(C)OC1=CC(NC(C)=O)=C(Cl)C=C1Cl QPJSUIGXIBEQAC-UHFFFAOYSA-N 0.000 description 9
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 6
- 239000011651 chromium Substances 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 229910017604 nitric acid Inorganic materials 0.000 description 6
- 150000007513 acids Chemical group 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 239000008237 rinsing water Substances 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 3
- 235000011941 Tilia x europaea Nutrition 0.000 description 3
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 3
- 239000004202 carbamide Substances 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000004571 lime Substances 0.000 description 3
- 229910000000 metal hydroxide Inorganic materials 0.000 description 3
- 150000004692 metal hydroxides Chemical class 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 3
- 239000007800 oxidant agent Substances 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 239000002351 wastewater Substances 0.000 description 3
- 230000003213 activating effect Effects 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 239000008267 milk Substances 0.000 description 2
- 210000004080 milk Anatomy 0.000 description 2
- 235000013336 milk Nutrition 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- DBVJJBKOTRCVKF-UHFFFAOYSA-N Etidronic acid Chemical group OP(=O)(O)C(O)(C)P(O)(O)=O DBVJJBKOTRCVKF-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- -1 ammonium ions Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910001634 calcium fluoride Inorganic materials 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 150000002826 nitrites Chemical class 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
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
- 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
-
- 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
- C23G1/086—Iron or steel solutions containing HF
-
- 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
- C23G1/36—Regeneration of waste pickling liquors
Definitions
- the invention relates to a method for the pickling treatment of stainless steel or stainless steel surfaces.
- the inventive method is suitable for the surface treatment of all alloys and structural forms of stainless steel.
- the inventive method allows the recycling of wastewater from the lo process.
- the pickling treatment is usually carried out so that a top layer of material is chemically dissolved and removed in the pickling baths. As a result of this erosion, all contaminants contained on and in the removed material layer are removed.
- Prior art pickling processes are based on the use of hydrofluoric acid, a secondary mineral acid such as nitric acid, sulfuric acid or phosphoric acid and an oxidizing agent such as nitric acid or hydrogen peroxide.
- a secondary mineral acid such as nitric acid, sulfuric acid or phosphoric acid
- an oxidizing agent such as nitric acid or hydrogen peroxide.
- nitric acid this fulfills both the function of the secondary mineral acid and that of the oxidizing agent.
- nitric acid is very disadvantageous in terms of environmental hazard and occupational safety.
- Essential constituents of stainless steel pickling are hydrofluoric acid and a suitable oxidizing agent.
- a secondary acid when using hydrogen peroxide in place of nitric acid.
- the addition of this secondary acid serves the purpose of counteracting the lower stability of the hydrogen peroxide at higher concentration of dissolved metals in the pickling baths.
- the present invention seeks to overcome the foregoing disadvantages of the prior art.
- the aim of the invention is in particular a pickling process in which it is possible to work with the lowest possible concentration of hydrofluoric acid and with hydrogen peroxide without secondary acids, for example in the presence of a suitable stabilizer for hydrogen peroxide.
- the method according to the invention should be applicable to all alloys and structural types of stainless steel.
- the present invention is based on the finding that it is possible to achieve the objectives of the invention by means of a suitable pretreatment in the pickling process.
- the inventors have found that for pre-treatment or activation of the pickling a solution containing hydrofluoric acid is suitable, the concentration of which is usually adjusted so that it is close to the concentration of the actual pickling bath, preferably even something about it.
- hydrofluoric acid-containing (HF) solutions are used in a two-stage process - a pretreatment (activation) and the actual pickling.
- HF hydrofluoric acid-containing
- the hydrofluoric acid-containing solution in the first stage of the process essentially uses hydrofluoric acid (HF) at a concentration which can be close to (or equal to) the pickling bath concentration without the addition of H 2 O 2 .
- the concentration of the hydrofluoric acid in the first stage is about 0.2 to 5 wt%, preferably 0.5 to 3 wt%. Since the first process step essentially serves for pretreatment or activation of the pickling material, no further components are required in this activation bath.
- the person skilled in the art will be able to find a suitable concentration depending on the material to be treated and the hydrofluoric acid concentration in the following method step with simple experiments.
- the concentration of hydrofluoric acid in the actual pickling process is then about 0.2 to 5 wt .-%, preferably 0.5 to 3 wt .-%.
- the concentration of hydrogen peroxide in the pickling bath is usually 10 to 30% by weight, preferably 18 to 22% by weight, and more preferably about 20% by weight.
- a suitable stabilizer may include, for example, urea. Urea can be used both alone and in conjunction with other stabilizers, such as ammonium ions. Other suitable stabilizers are, for example, alylidenediphosphonic acid. In addition, blends of urea and one or more alkanediphosphonic acids (including the salts) may generally be used for stabilization. A particularly suitable stabilizer is 1-hydroxyethane-1,1-diphosphonic acid. Stabilizers are disclosed in particular in EP-AI 903 081, which is incorporated herein by reference.
- the stainless steel surfaces to be coated are usually subjected to a dipping time of 20 seconds to a maximum of 5 minutes in the first method step. No intermediate step such as rinsing is required before the dressing is introduced into the second process stage.
- the second process stage is then initiated in a conventional manner but usually also without delay after the first process step.
- About the pickling time results in a well controllable pickling attack without risk of damage by over-pickling. This has proved equally true for all alloys and microstructures of stainless steel. Only the concentration of hydrofluoric acid is to be adjusted to a certain extent of the stainless steel quality to be refined in order to adjust the speed of the pickling attack to the desired level.
- the entry of hydrofluoric acid from the activation (pretreatment) in the pickling bath can be chosen so that the consumption of hydrofluoric acid in the pickling bath and the carry-over into the rinsing process are largely compensated. In the pickling bath, therefore, only the consumed and removed hydrogen peroxide must be supplemented. After the pickling bath is usually run in excess with hydrogen peroxide, the addition is not critical and does not require the analytical effort required for pickling baths according to the prior art.
- the concentration of hydrofluoric acid for processing austenitic chromium-nickel steels is in the range of 1.5 to 3.0%, for processing ferritic steels at 0.5 to 1%. In the case of ferritic steels, one can even assume that the hydrofluoric acid baths used are no longer classified as toxic but merely as corrosive.
- the concentration of hydrogen peroxide in the pickling baths is in the range of 10% to 30% by weight, preferably 20% by weight.
- the concentration of stabilizer in the pickling bath is 2% by weight to 10% by weight, preferably 5% by weight to 8% by weight.
- the inventive method operates at room temperature (maximum about 40 0 C), so that no complex heating and temperature control are required.
- Example 1 Pickling bath for austenitic chromium-nickel steels Composition of the activating bath: 2.1% HF, balance water, activating time 3 min
- Example 2 Pickling bath for chromium steels from 14% chromium content
- Composition of the activation bath 1.0% HF, balance water, activation time 2 min.
- Pickling bath composition 1.0% HF, 5.0% stabilizer, 20% H 2 O 2 , balance water
- Example 3 Stainless steels with 9% to 13% chromium content Composition of the activation bath: 0.5% HF, balance water, activation time 2 min Pickling bath composition: 0.5% HF, 5.0% stabilizer, 20% H 2 O 2 , Rest water
- the pickling baths according to the invention contain pollutants exclusively hydrofluoric acid and the dissolved metal salts of hydrofluoric acid, which are removed from the pickling bath in the rinsing water.
- the treatment of the rinsing water is advantageously carried out with lime, which is stoichiometrically tuned to the amount of fluoride.
- lime which is stoichiometrically tuned to the amount of fluoride.
- the fluorides are precipitated to a concentration below 1 mg / l, the metals are largely converted into metal hydroxides and deposited as solids.
- the neutralized rinse water can easily be used for the treatment of the lime milk or discharged into the sewage system, since it no longer contains salts such as nitrates, nitrites, sulfates or phosphates.
- the freedom of salts opens up an advantageous solution for recycling the water: After neutralization, the rinsing water is recovered by evaporation and returned to the rinsing process as condensate. About the amount of recycled condensate is only the amount of compensation of the addition of hydrogen peroxide introduced into the pickling bath additional water. The thickened contents of the evaporator bottom are filtered, the fluorides and metal hydroxides are separated as a solid. The filtrate contains most of the Stabilizer and is returned to the pickling bath, so that the consumption of stabilizer is minimized.
- the filter cake contains only metal hydroxides and offers optimal conditions for the economic recovery of the metals.
- Rinsing water from a pickling bath with 50 g / l Fe and 10 g / l Cr contains 5% strength
- Ni 300 mg / 1 Ni
- the treatment was carried out by neutralizing with lime milk to pH 8-9, sedimentation and separation of the sludge by filtration. Fluoride and heavy metals were quantitatively removed. The ingredients of the stabilizer remained in the filtrate.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE200910038795 DE102009038795A1 (de) | 2009-08-25 | 2009-08-25 | Beizverfahren für Edelstahl |
PCT/EP2010/005040 WO2011023319A1 (de) | 2009-08-25 | 2010-08-17 | Beizverfahren für edelstahl |
Publications (1)
Publication Number | Publication Date |
---|---|
EP2470689A1 true EP2470689A1 (de) | 2012-07-04 |
Family
ID=43050930
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP10745563A Withdrawn EP2470689A1 (de) | 2009-08-25 | 2010-08-17 | Beizverfahren für edelstahl |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP2470689A1 (de) |
DE (1) | DE102009038795A1 (de) |
WO (1) | WO2011023319A1 (de) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102013010080A1 (de) * | 2013-06-14 | 2014-12-18 | Poligrat Gmbh | Verfahren zur Oberflächenbehandlung von Corten-Stahl |
CN113740142B (zh) * | 2020-05-27 | 2024-07-12 | 宝山钢铁股份有限公司 | 一种镀锌板基体氢含量的获取方法 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT228137B (de) * | 1960-06-10 | 1963-06-25 | Othmar Ing Ruthner | Verfahren zur Rückgewinnung der nach dem Beizen von Metallen im Spülwasser enthaltenen ausgeschleppten Beizsäure |
WO2002081777A1 (en) * | 2001-04-09 | 2002-10-17 | Ak Properties, Inc. | Hydrogen peroxide pickling scheme for stainless steel grades |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1657228A (en) * | 1926-06-02 | 1928-01-24 | Allegheny Steel Co | Method of picking chromium-iron alloys |
SE381289B (sv) * | 1973-06-21 | 1975-12-01 | Nyby Bruk Ab | Tvastegsbetningsforfarande |
AT374508B (de) * | 1982-07-01 | 1984-05-10 | Ruthner Industrieanlagen Ag | Verfahren zur aufarbeitung verbrauchter beizoder aetzloesungen auf der basis von salpeter-flussaeure |
US5154774A (en) * | 1985-09-19 | 1992-10-13 | Ugine Aciers De Chatillon Et Gueugnon | Process for acid pickling of stainless steel products |
DE4142629C2 (de) * | 1991-12-21 | 1994-12-08 | Wurster Gerd | Verfahren zum Verdampfen von Abwasser und/oder Spülwasser |
AT404030B (de) * | 1995-02-15 | 1998-07-27 | Andritz Patentverwaltung | Verfahren zur beize von materialien aus stahl, insbesondere edelstahl |
SE510298C2 (sv) * | 1995-11-28 | 1999-05-10 | Eka Chemicals Ab | Sätt vid betning av stål |
US6149744A (en) * | 1997-10-28 | 2000-11-21 | Kawasaki Steel Corporation | Method of making austenitic stainless steel sheet |
GB9807286D0 (en) * | 1998-04-06 | 1998-06-03 | Solvay Interox Ltd | Pickling process |
DE19833990A1 (de) * | 1998-07-29 | 2000-02-10 | Metallgesellschaft Ag | Beizmittel für Edelstähle |
IT1312556B1 (it) * | 1999-05-03 | 2002-04-22 | Henkel Kgaa | Processo di decapaggio di acciaio inossidabile in assenza di acidonitrico ed in presenza di ioni cloruro |
PL1903081T3 (pl) | 2006-09-19 | 2015-05-29 | Poligrat Gmbh | Stabilizator do kwaśnych kąpieli polerskich zawierających metal |
-
2009
- 2009-08-25 DE DE200910038795 patent/DE102009038795A1/de not_active Withdrawn
-
2010
- 2010-08-17 WO PCT/EP2010/005040 patent/WO2011023319A1/de active Application Filing
- 2010-08-17 EP EP10745563A patent/EP2470689A1/de not_active Withdrawn
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT228137B (de) * | 1960-06-10 | 1963-06-25 | Othmar Ing Ruthner | Verfahren zur Rückgewinnung der nach dem Beizen von Metallen im Spülwasser enthaltenen ausgeschleppten Beizsäure |
WO2002081777A1 (en) * | 2001-04-09 | 2002-10-17 | Ak Properties, Inc. | Hydrogen peroxide pickling scheme for stainless steel grades |
Non-Patent Citations (1)
Title |
---|
See also references of WO2011023319A1 * |
Also Published As
Publication number | Publication date |
---|---|
WO2011023319A1 (de) | 2011-03-03 |
DE102009038795A1 (de) | 2011-05-05 |
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