US3565688A - Methods of pickling ferrous metals - Google Patents
Methods of pickling ferrous metals Download PDFInfo
- Publication number
- US3565688A US3565688A US732059A US3565688DA US3565688A US 3565688 A US3565688 A US 3565688A US 732059 A US732059 A US 732059A US 3565688D A US3565688D A US 3565688DA US 3565688 A US3565688 A US 3565688A
- Authority
- US
- United States
- Prior art keywords
- solution
- pickling
- acid
- nitric acid
- urea
- 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.)
- Expired - Lifetime
Links
- 239000002184 metal Substances 0.000 title abstract description 24
- 229910052751 metal Inorganic materials 0.000 title abstract description 24
- 238000005554 pickling Methods 0.000 title abstract description 20
- 238000000034 method Methods 0.000 title abstract description 12
- -1 ferrous metals Chemical class 0.000 title description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 abstract description 20
- 229910017604 nitric acid Inorganic materials 0.000 abstract description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 18
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 abstract description 17
- 239000004202 carbamide Substances 0.000 abstract description 17
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 abstract description 14
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 abstract description 9
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 9
- 238000009825 accumulation Methods 0.000 abstract description 4
- 239000000243 solution Substances 0.000 description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 16
- 238000006243 chemical reaction Methods 0.000 description 13
- 239000002253 acid Substances 0.000 description 10
- 229910052742 iron Inorganic materials 0.000 description 8
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 4
- 238000011109 contamination Methods 0.000 description 3
- 238000004090 dissolution Methods 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 238000007792 addition Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 1
- 235000021110 pickles Nutrition 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910001868 water Inorganic materials 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
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/085—Iron or steel solutions containing HNO3
Definitions
- a method of pickling ferrous metal comprising treating said ferrous metal with a solution containing dilute nitric acid, said solution COntaining urea to inhibit the accumulation of nitrous acid and oxides of nitrogen in the solution.
- This invention concerns a method of pickling ferrous metal.
- Ferrous metal such as, for example, mild steel, which has been subjected to manufacturing processes at high temperatures becomes coated with a layer of surface contamination, mainly metal oxides. This contamination must be removed before any subsequent treatment can be applied to the metal surface.
- the contamination is often removed by pickling the metal in an acid pickling bath, the acid generally being a dilute solution of sulphuric or hydrochloric or phosphoric acid or, very occasionally, dilute nitric acid.
- the first or desirable reaction which produces a good quality pickled surface yields ammonium nitrate and ferrous nitrate
- the second or undesirable reaction is more complex.
- the iron liberates nitrous acid and oxides of nitrogen from the nitric acid.
- the nitrous acid and oxides of nitrogen tend to remain near the surface of the metal, and react further with the iron.
- the products of this reaction also tend to remain near the surface of the metal and are thought to promote the aforementioned second or undesirable reaction and inhibit the first or desirable reaction. If the undesirable reaction is allowed to continue, then the quality of the pickled surface produced will quickly deteriorate.
- Our invention therefore comprises a method of pickling ferrous metal comprising treating said ferrous metal with a solution containing dilute nitric acid, said solution containing urea to inhibit the accumulation of nitrous acid and oxides of nitrogen in the solution.
- the concentration of the nitric acid in the solution does not exceed 5% by weight.
- the urea is present in a concentration of 25 grams of urea per litre of solution.
- the pickling is effected at a temperature not exceeding 20 C.
- the solution is agitated.
- the invention also comprises ferrous metal when pickled by the method set forth above.
- urea destroys nitrous acid by reacting with it to give nitrogen, carbon dioxide and water
- the undesirable reaction is further inhibited by maintaining the temperature of the solution approximately in the range 17-20" C. Agitation of the solution by means, for example, of pumping has also been found to inhibit the undesirable reaction.
- nitric acid in the solution is 5% by weight, although acceptable pickling quality is obtained at acid concentrations up to 15% by weight.
- a higher concentration is unsuitable, since urea is insoluble in cold dilute nitric acid of concentration above 15% by weight, and thus cannot in this case inhibit the undesirable reaction.
- the only significant difference in performance between a relatively low and a relatively high acid concentration is that the latter removes iron from the pickled surface at a faster rate.
- Pickling ferrous metals according to our invention may have the following advantages.
- the metal surface can be deeply and uniformly etched without the application of an electric current.
- the acid can be used cold and the products of dis solution are very soluble in cold acid.
- the pickled surface is to some extent inhibited against rusting.
- a method of pickling ferrous metal comprising treating said ferrous metal with an aqueous solution consisting of nitric acid and urea, said nitric acid not exceeding 15% by weight, said urea being present in amounts sufiicient to inhibit the accumulation of nitrous acid and oxides of nitrogen in the solution, said treatment being carried out at a temperature not exceeding 20 C., thereby preventing said nitrous acid and oxides of nitrogen from reacting with said ferrous metal.
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)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB26585/67A GB1126305A (en) | 1967-06-08 | 1967-06-08 | Improvements in or relating to methods of pickling ferrous metals |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3565688A true US3565688A (en) | 1971-02-23 |
Family
ID=10245939
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US732059A Expired - Lifetime US3565688A (en) | 1967-06-08 | 1968-05-27 | Methods of pickling ferrous metals |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US3565688A (en:Method) |
| BE (1) | BE715984A (en:Method) |
| DE (1) | DE1771553A1 (en:Method) |
| FR (1) | FR1567825A (en:Method) |
| GB (1) | GB1126305A (en:Method) |
| NL (1) | NL6808104A (en:Method) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4477009A (en) * | 1982-03-08 | 1984-10-16 | Walker Richard M | Tungsten carbide reactive process |
| US4678541A (en) * | 1985-06-03 | 1987-07-07 | Solvay & Cie. (Societe Anonyme) | Baths and process for chemical polishing of stainless steel surfaces |
| CN102888607A (zh) * | 2012-09-24 | 2013-01-23 | 中国人民解放军第五七一九工厂 | 快速去除镍镉扩散镀层的清除剂组合物及其退镀方法 |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2048311A (en) * | 1979-04-12 | 1980-12-10 | Sumitomo Metal Ind | Chemical pickling stainless steel |
| FR2562097A1 (fr) * | 1984-03-28 | 1985-10-04 | Andritz Ag Maschf | Procede pour le decapage d'aciers allies, de cuivre, d'alliages de metaux lourds non-ferreux, de titane, de zirconium, de tantale, etc. au moyen de bains d'acide nitrique |
-
1967
- 1967-06-08 GB GB26585/67A patent/GB1126305A/en not_active Expired
-
1968
- 1968-05-27 US US732059A patent/US3565688A/en not_active Expired - Lifetime
- 1968-05-31 BE BE715984D patent/BE715984A/xx unknown
- 1968-06-07 DE DE19681771553 patent/DE1771553A1/de active Pending
- 1968-06-07 NL NL6808104A patent/NL6808104A/xx unknown
- 1968-06-07 FR FR1567825D patent/FR1567825A/fr not_active Expired
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4477009A (en) * | 1982-03-08 | 1984-10-16 | Walker Richard M | Tungsten carbide reactive process |
| US4678541A (en) * | 1985-06-03 | 1987-07-07 | Solvay & Cie. (Societe Anonyme) | Baths and process for chemical polishing of stainless steel surfaces |
| AU579474B2 (en) * | 1985-06-03 | 1988-11-24 | Solvay & Cie Societe Anonyme | Baths and process for chemical polishing of stainless steel surfaces |
| CN102888607A (zh) * | 2012-09-24 | 2013-01-23 | 中国人民解放军第五七一九工厂 | 快速去除镍镉扩散镀层的清除剂组合物及其退镀方法 |
| CN102888607B (zh) * | 2012-09-24 | 2014-08-06 | 中国人民解放军第五七一九工厂 | 快速去除镍镉扩散镀层的清除剂组合物及其退镀方法 |
Also Published As
| Publication number | Publication date |
|---|---|
| NL6808104A (en:Method) | 1968-12-09 |
| GB1126305A (en) | 1968-09-05 |
| DE1771553A1 (de) | 1972-02-10 |
| BE715984A (en:Method) | 1968-10-16 |
| FR1567825A (en:Method) | 1969-05-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| RU2072397C1 (ru) | Раствор и способ травления нержавеющей стали | |
| US2564549A (en) | Pickling treatment | |
| US3460989A (en) | Method of treating ferrous metal surfaces | |
| US6126755A (en) | Metal surface treatment solutions and process | |
| JP2700061B2 (ja) | リン酸塩皮膜の形成方法 | |
| US3140203A (en) | Method of and composition for treating aluminum and aluminum alloys | |
| US3565688A (en) | Methods of pickling ferrous metals | |
| US3537926A (en) | Chemical brightening of iron-containing surfaces of workpieces | |
| US2876144A (en) | Metal pickling solutions and methods | |
| US3507795A (en) | Composition for removal of copper and copper oxide scales from boilers | |
| US2737498A (en) | Product for and process of treating metallic articles before coating | |
| US2511988A (en) | Pickling process | |
| US4678541A (en) | Baths and process for chemical polishing of stainless steel surfaces | |
| JP3160051B2 (ja) | 酸洗促進剤、酸洗促進剤を含んだ酸洗液組成物およびこれを用いる金属の酸洗促進方法 | |
| US2295545A (en) | Treatment of metal | |
| US3094489A (en) | Method and composition for brightening aluminum | |
| US2878146A (en) | Method of de-oxidizing metal surfaces | |
| US3647698A (en) | Composition for cleaning aluminum and method utilizing same | |
| US3004879A (en) | Brightening and cleaning composition and treatment for magnesium and magnesium-base alloys | |
| US2057813A (en) | Process for hardening iron and steel alloys and article produced thereby | |
| RU2061101C1 (ru) | Раствор для одновременного травления и обезжиривания металлов | |
| JPS58110682A (ja) | ＮＯｘ発生を抑制したステンレス鋼の酸洗方法 | |
| US3510365A (en) | Process of pretreating ferrous metal surfaces before phosphatizing | |
| US3479293A (en) | Process and composition for etching ferrous metal surfaces | |
| US2392404A (en) | Pickling bath for ferrous metals and inhibitor for use therein |