US2615840A - Electrolytic method to remove rust - Google Patents
Electrolytic method to remove rust Download PDFInfo
- Publication number
- US2615840A US2615840A US87261A US8726149A US2615840A US 2615840 A US2615840 A US 2615840A US 87261 A US87261 A US 87261A US 8726149 A US8726149 A US 8726149A US 2615840 A US2615840 A US 2615840A
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- United States
- Prior art keywords
- gal
- alkali metal
- bath
- article
- vat
- Prior art date
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Links
- 238000000034 method Methods 0.000 title claims description 30
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 title claims description 25
- 229910052751 metal Inorganic materials 0.000 claims description 24
- 239000002184 metal Substances 0.000 claims description 24
- 229910052783 alkali metal Inorganic materials 0.000 claims description 17
- 150000001340 alkali metals Chemical class 0.000 claims description 12
- 239000000080 wetting agent Substances 0.000 claims description 11
- 238000005260 corrosion Methods 0.000 claims description 9
- 230000007797 corrosion Effects 0.000 claims description 9
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 claims description 8
- 150000004645 aluminates Chemical class 0.000 claims description 8
- 239000007864 aqueous solution Substances 0.000 claims description 8
- 150000002739 metals Chemical class 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 7
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims description 6
- 229910001514 alkali metal chloride Inorganic materials 0.000 claims description 4
- 229910001515 alkali metal fluoride Inorganic materials 0.000 claims description 3
- 239000000243 solution Substances 0.000 description 26
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 15
- 238000011282 treatment Methods 0.000 description 15
- 239000000203 mixture Substances 0.000 description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- -1 ferrous metals Chemical class 0.000 description 11
- 238000009991 scouring Methods 0.000 description 8
- 238000005868 electrolysis reaction Methods 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- 238000009434 installation Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 235000011121 sodium hydroxide Nutrition 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 4
- 239000003792 electrolyte Substances 0.000 description 4
- 150000002191 fatty alcohols Chemical class 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 239000003921 oil Substances 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 238000009412 basement excavation Methods 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 230000008929 regeneration Effects 0.000 description 3
- 238000011069 regeneration method Methods 0.000 description 3
- 229910001369 Brass Inorganic materials 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- 239000004166 Lanolin Substances 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 2
- 150000001298 alcohols Chemical class 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000010951 brass Substances 0.000 description 2
- 239000010974 bronze Substances 0.000 description 2
- KXZJHVJKXJLBKO-UHFFFAOYSA-N chembl1408157 Chemical compound N=1C2=CC=CC=C2C(C(=O)O)=CC=1C1=CC=C(O)C=C1 KXZJHVJKXJLBKO-UHFFFAOYSA-N 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- TVQLLNFANZSCGY-UHFFFAOYSA-N disodium;dioxido(oxo)tin Chemical compound [Na+].[Na+].[O-][Sn]([O-])=O TVQLLNFANZSCGY-UHFFFAOYSA-N 0.000 description 2
- 239000004519 grease Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000003350 kerosene Substances 0.000 description 2
- 229940039717 lanolin Drugs 0.000 description 2
- 235000019388 lanolin Nutrition 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 2
- 229910052911 sodium silicate Inorganic materials 0.000 description 2
- 229940079864 sodium stannate Drugs 0.000 description 2
- MOMKYJPSVWEWPM-UHFFFAOYSA-N 4-(chloromethyl)-2-(4-methylphenyl)-1,3-thiazole Chemical compound C1=CC(C)=CC=C1C1=NC(CCl)=CS1 MOMKYJPSVWEWPM-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- YZCKVEUIGOORGS-UHFFFAOYSA-N Hydrogen atom Chemical compound [H] YZCKVEUIGOORGS-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000004902 Softening Agent Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 229910001508 alkali metal halide Inorganic materials 0.000 description 1
- 150000008045 alkali metal halides Chemical class 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 1
- ANBBXQWFNXMHLD-UHFFFAOYSA-N aluminum;sodium;oxygen(2-) Chemical compound [O-2].[O-2].[Na+].[Al+3] ANBBXQWFNXMHLD-UHFFFAOYSA-N 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- 230000002999 depolarising effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000008233 hard water Substances 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011221 initial treatment Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 235000013980 iron oxide Nutrition 0.000 description 1
- VBMVTYDPPZVILR-UHFFFAOYSA-N iron(2+);oxygen(2-) Chemical class [O-2].[Fe+2] VBMVTYDPPZVILR-UHFFFAOYSA-N 0.000 description 1
- 239000011133 lead Substances 0.000 description 1
- 159000000003 magnesium salts Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000007127 saponification reaction Methods 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910001388 sodium aluminate Inorganic materials 0.000 description 1
- 235000019983 sodium metaphosphate Nutrition 0.000 description 1
- 235000019795 sodium metasilicate Nutrition 0.000 description 1
- 239000001488 sodium phosphate Substances 0.000 description 1
- 229910000162 sodium phosphate Inorganic materials 0.000 description 1
- HVTHJRMZXBWFNE-UHFFFAOYSA-J sodium zincate Chemical compound [OH-].[OH-].[OH-].[OH-].[Na+].[Na+].[Zn+2] HVTHJRMZXBWFNE-UHFFFAOYSA-J 0.000 description 1
- 229940071182 stannate Drugs 0.000 description 1
- 125000005402 stannate group Chemical group 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F1/00—Electrolytic cleaning, degreasing, pickling or descaling
Definitions
- This invention relates to processes and compositions for treating articles to remove rust and other deposits from metallic articles. It relates particularly to processes and compositions for removing rust from ferrous metals and surface coatings, such as, carbonaceous deposits, cement, paint, enamel, and other materials from the surfaces of ferrous metals, copper, lead and their alloys.
- the present invention provides a method and a composition whereby articles of substantially any size can be cleaned and freed from rust to such an extent that the surfaces of the article are rendered clean and shiny in appearance, even though the part may have been rusted or corroded to such an extent that it appeared to be useless.
- the process and the cleaning composition have the characteristic of acting so completely on corroded or rusted surfaces as well as such great penetrating power that, for example, a nut which has rusted solidly to a bolt is cleaned sufliciently that it can be easily unscrewed after the treatment.
- the process is applicable to the treatment of many kinds of devices, such as, machine tools, typewriters and other devices which have become corroded or rusted to such an extent, as, for example, by immersion in water over a long period of time. Frequently, such devices can be placed in a usable condition by treatment in accordance with the present invention Without disassembly and reassembly.
- the article to be cleaned or freed from rust, after being scoured and rinsed in hot water is used as a cathode in an electrolytic bath which consists essentially of an aqueous solution of an alkali metal hydroxide, an alkali metal cyanide, one or more alkali metal halides, a suitable peptizing salt, such as, for example, an alkali metal metasilicate or an alkali aluminate and a wetting agent, such as sulfated fatty alcohols or lsulfonated products.
- an electrolytic bath which consists essentially of an aqueous solution of an alkali metal hydroxide, an alkali metal cyanide, one or more alkali metal halides, a suitable peptizing salt, such as, for example, an alkali metal metasilicate or an alkali aluminate and a wetting agent, such as sulfated fatty alcohols or lsulfonated products.
- the bath may be benetted by the addition of small quantities of alkali metal zincates or stannates. These materials, when combined with the other components used, form a very thin coherent ilm on the surface of the article when it has been cleaned or de-rusted, this thin lm providing corrosion resistance in the article when it is stored.
- the relative proportions of the various components of the solution depend upon various factors, and, in particular, on the speed with which it is desired t0 carry out the derusting or rustremoving operation, on the quantity and nature of the rust or other deposit to be removed. Inasmuch as some parts may have deposits of varying characteristics, these deposits may have to be removed simultaneously.
- the composition of the bath must be such that it can be used for such purposes within relatively wide limits controlled chiefly by economic conditions and the cost of the necessary chemicals.
- the treatment of the article is preferablyl effected at ambient temperature at a low continuous voltage and a relatively high current density.
- the part to be cleaned is immersed in the electrolyte as the negative pole or cathode of the circuit while the bath is vigorously stirred, as, for example, by the introduction of air under pressure into the lower part of the vat.
- the current is reversed and electrolysis is continued with the article as an anode for a period of time equal to about 1/5 of the time during which electrolysis was carried forward with the part as a cathode.
- Fig. 1 is an elevation of the treatment vat, part of which has been removed to show the inside arrangement.
- Fig. 2 is a plan view corresponding to Fig. 1.
- Fig. 3 shows on a larger scale the arrangement, inside of the vat, of the anodes and of the air-inlet pipe, as well as the arrangement of the bus bars arranged outside and connected with the other pole of the source of current.
- Fig. 4 is an end view of one of the terminals connecting the connecting cables with the bus bars arranged outside of the vat.
- Fig. 5 is a view, partly in elevation and partly in section of the part shown on Fig. 4.
- Fig. 6 shows the end of a connecting cable provided with a terminal part which fits onto the terminals and members which connect with Fig. 9 is an end view of the part shown onV Fig. 8.
- Fig. 10 is an elevation view with the ends shown in section of a bar fastened above the vat, and making it possible to suspend on same the light-weight objects to be treated.
- Figs. 11 and 12 are an elevation view and a plan view of a basket intended to receive the small parts to be treated.
- Fig. 13 shows in vertical section a portion of the scouring vat provided with a gas heating device.
- Fig. 14 is a section along XIV- XIV of Fig. 13.
- Fig. 15 is an elevation of the general installation. 4
- Fig. 16 is a plan view of the same installation.
- the parts to be derusted are first of all carefully scoured in order to enable the electrolyte to wet all the portions of the part.-
- This scouring like all the other operations of the process, is carried out in a vat of suitable dimensions, made of any material capable of withstanding the action of the liquids it is to contain.
- the scouring may be effected in a hot solution of caustic soda to which a wetting agent of the sulfated alcohol or sulfonated oil type may be added.
- the vat containing this solution is heated to about 80 C., the bath being constantly stirred during the operation.
- a 40 per cent solution of caustic soda is satisfactory for the cleaning operation, although solutions of varying concentrations may be used.
- the part After the part has remained .from fifteen to thirty minutes in the scouring bath, the part is rinsed with hot water for five to ten minutes in a vat similar to the scouring vat and then it is immersed in the derusting bath.
- the derusting bath is susceptible to considerable variation depending upon the conditions. of use, but preferably the components thereof should be present in about the proportions indicated in the following table.
- Wetting agent sulfated fatty alcohol or sulfonated products le to 14 oz./gal.
- the 'solution may include alkali metal stannate or zincate, l to 3 oz./gal.
- the preferred bath is about a 30 Baume solution but it will be understood that the concentration will vary depending upon the variation in proportions of the components as set forth in the table.
- the water available for the .making of the solution is hard Water
- the alkali metal hydroxide for example,
- a sodium hydroxide is necessary in order to provide a solution of low electrical resistivity, thereby permitting the use of substantial current densities. It also acts to remove grease by emulsilication or saponification. It provides a solution of substantially constant pH value, and, when electrolyzed, produces a copious evolution of hydrogen and oxygen which facilitate the removal of scale or rust from the article by their mechanical action.
- the alkali metal cyanide for example, sodium cyanide, is beneficial in the removal of thin films of oxide, especially on non-ferrous articles. It also has the advantages of providing a solution of low polarization and thereby facilitates the rate of scale penetration and rust removal.
- the alkali metal chloride acts as a strong peptizer and therefore facilitates scale removal. Also, the chloride ion is a very active agent tending to promote scale penetration and the regeneration of the various types of salts used in the process. It also has a strong depolarizing effect.
- the alkali metal ,uorida for example, sodium uoride, is similar in its action to the sodium chloride but is even more reactive so that the effects produced by the chloride ion are enhanced by the presence of the fluoride.
- the sodium silicate or aluminate is used on account of its peptizing action, that is to say, at the time of the electrolysis, the one of the agents used decomposes, giving an element which remains in semi-colloidal form-silica, silicon hydroxide or silicio acid in the case of silicate, aluminum hydroxide in the case of aluminate, which element acts mechanically as an abrasive when it is dispersed in the solution.
- the wetting agent which is preferably a sulfonated oil type of compound or a sulfated alcohol, improves the penetrating power of the solution so that the composition tends to penetrate even into most minute crevices or intersticcs in the article, thereby facilitating the removal of rust or other unwanted surface impurities from the article.
- ⁇ It also has a tendency to decrease the danger of a back E. M. F. in the .solution during electrolysis since it decreases the surface tension of. the liquid and thereby enables the gases produced to pass readily from the solution.
- the wetting agent must, of course, not be affected by the presence of nascent oxygen and hydrogen inthe bath, it must be stable at the high pH value of the solution and it must be efficient and have a long operating life.
- the main purpose of the sodium phosphate is to soften hard waters ⁇ and to maintain the calcium and magnesium salts in solution while permitting the best possible dissolutionv of the chemical products used.
- the strongly adhering iron oxides may be reduced by the action of nascent hydrogen in accordance with the formula FezOs-l-Gl-IzZFe--HQO so that metal is deposited on the part which adds itself to the anode-cathode transfer, thereby partly replacing the metal lost through oxidation.
- the part being treated is electrolyzed for a period from thirty minutes to three hours according to the degree of oxidation of the parts and at a current density between about 3 and 31/2 amperes per square decimeter.
- this rst period of the treatment during which the part to be derusted is used as a cathode, has elapsed, current is reversed and the article is electrolyzed as an anode for a period about one-iifth as long as the previous period.
- the concentration of the alkaline chloride should not exceed the limits given above.
- the iron previously deposited by electrolysis may be slightly oxidized, but the oxide formed is immediately dissolved by the cyanide and at the end of the treatment, the parts have a shiny appearance and are perfectly clean. This action of the cyanide partly transforms the alkaline cyanide into complex salts with a base of iron, ferrior ferro-cyanides. thereby making the solution weaker in cyanide so that it is necessary to add cyanide periodically to the bath.
- the electrolytic bath may be maintained at about 30 Baume by adding to same from time to time, either water when the density is too high, or, when the density of the bath is too low, a mixture of suitable salts called regeneration mixture and containing a high percentage of cyanide.
- the composition of this regeneration mixture may be included within the following limits:
- washing electrolyte They must stay in the Washing electrolyte but also to bring them to a sufficient temperature to enable them to dry rapidly. They are subsequently immersed in an oil or other similar bath which prevents their being oxidized by the air. A very satisfactory bath consists of a 20% solution of lanolin in kerosene. The parts are subsequently dried and may be used again immediately.
- a specific example of the process is as follows: A metallic article, for example, a rusted steel article, is degreased and partially cleaned by introducing it into a bath consisting of a 40 per cent solution of caustic soda heated to a temperature of about and containing a small amount of a suitable wetting agent such las a sulfated fatty alcohol. The part is left in the bath for about twenty minutes while the bath is stirred continuously until it appears that grease and like deposits have been removed from the article. The article is then rinsed for about 5 to l0 minutes in hot Water and then is transferred to an electrolytic bath having the following composition:
- the sodium stannate can be omitted if desired.
- the article is connected in an electrical circuit and immersed as a cathode in the electrolytic bath.
- the article is electrolyzed at a current density of 31A? amperes per square decimeter for a period of about two hours.
- the current is reversed and electrolysis is continued at the same current density, but with the part as an anode for an additional period of about twenty-five minutes.
- the current is shut olf and the article is removed, drained and washed in hot water for a sufficient period of time to remove the last traces of the electrolyte and also to heat the article to a sufficiently high temperature to enable it to dry quickly.
- the article is then immersed in a bath consisting of a twenty per cent solution of lanolin in kerosene andv subsequently drained, leaving only a thin surface iilm of the solution on the parts for preventing oxidation.
- the process may be practiced with a series of vats of materials resistant vto corrosion or attack by thev above-mentioned chemical agents.
- vats described hereinafter may advantageously be made of sheets of soft steel, suitably reinforced by angles in accordance with the maximum weight and dimension of the parts to be treated.
- Figs. 1 and 2 show a vat which is well suited for the derusting operation proper.
- Vat l of '7 sheet metal has its sides and the' bottom lb welded together, and it is provided at its -upper part with an edge or flange 2 on which there are fastened wooden rails or supports 3 actingA as insulators to hold the current conductor bars ⁇ Il extending around the interior of the top of the vat.
- a conduit 5 supplied compressed air through descending tubes 6 to headers 'I placed near the bottom of the vat.
- the headers 'I are provided with nozzles 8 inclined at 45 in both directions.
- a copper bracket supported on the rail 3 is connected with one of the poles of the low voltage installation, which includes an inverter capable of allowing the maximum intensity to-pass, and on this part 9 there are fastened the four bus bars 4, of copper, between which there are attached the anodes II formed of plates of soft steel (Fig. 3).
- the bars and the anodes may be fastened by means of carpenters bolts Ill which extend through the members 3 and the bars 4 which are held at suitable spacing by washers I 2.
- the anodes are provided on the four sides of the vat and are spaced a short distance from the walls of the latter, from which they are electrically insulated.
- the second pole of the source of the current is connected with the outer bus bars I3 which'extend along one side of the Vat and which support a certain number of connectors I4 which form g connection terminals.
- These connectors are made of brass or phosphor bronze and they include a body having two slots I 5 therein which make it possible to receive two of the three bus bars I3.
- a hole I6 permits each bus bar I3 to be retained in a slot i5 by means of a bolt I D (Fig. 3).
- the connectors I4 also include a pipe connection I'I threaded on the outside and bored conically at Ila so as to constitute the female part of the connection.
- the male part fastened to the current supply cable I8 (Fig. 6) includes a hollow rod made of bronze or brass in which the cable I8 engages, which rod terminates at the other end in a cone I9 which is inserted in the cavity I'Ia of the female part and which is provided, at its portion where its diameter is largest, with a shoulder I9a which serves as a rest for a lock nut with a knurled surface 20.
- stirrup o f Fig. 7 consists of a U-shaped member, one of the arms of which is provided with a female connection member previously described, and Vof, a V-shaped notch 2l, The other arm is provided with a clamping screw 22.
- the connector shown in Figs. 8 and 9 can be fastened to a part being treated by means of a bolt which is screwed into the said part, and it includes the female connection member IT which is integral with a sleeve 2 3 ⁇ having a central hole 2t for receiving the fastening bolt, the two parts I1 and 23 being onset so as to receive tbenut 2D of the male part of the connector (Fig. 6).
- the vat there may be arranged at a suitable height a certain number of cross-members which may consist, for example, of beams, when the parts to be treated are heavy, the current being fed directly to the parts by means of the stirrups or anges 4just described, or when the to the parts parts are lighter in weight, they may consist of simple round bars 25 of suitable diameter, an example of which is shown on Fig. l0. These bars are provided with welded spacing rings 26.
- the parts to be treated are suspended on these cross-members by means of hooks, Ss or suitable chains.
- the rings 26 play an important part when the parts are suspended by means of chains because they prevent the latter from sliding during treatment.
- the scouring and rinsing vats of course are not provided with electrolyzing equipment, but they must be capable of being heated in such a manner as to bring the temperature of the liquid to about 80 C.
- Figs. 13 and le show an advantageous arrangement for heating of these vats by means of gas.
- Rows of gas burners 29 are arranged under the metal vat.
- a sheet metal shell 3S forms with the sides Ia a conduit for the hot gases which 'give off to the walls of the vat, during their scent, a large part of the heat which they con-
- the general installation may be understood in accordance with the arrangement shown on Figs. l5 and 16.
- the vats are arranged following each other in an excavation 25 so that the upper edge oi the vats is located approximately one meter above the ground, and, between the vats and the edges of the excavation, floor sections made of latticework make it possible to move all around the vats.
- the articles to be treated are introduced into a scouring vat 3! and the first rinsing vat 32, both gas heated by means of the rows of burner-s 29.
- the electrolytic vat or cell is adjacent to the rinsing bath 32.
- the second rinsing vat 33 which follows the electrolytic Vat or cell, is identical with vats 3l and 32.
- vats 32 and 33 In view of the fact that the parts remain in vats 32 and 33 only a short time, it would be possible to-provide for only one vat for the two washing operations. For the sake of most elicient operation of the installation, it is preferable to provide the two vats.
- the parts When leaving the rinsing in vat 33, the parts must be dried (drained), for this purpose they may be arranged on a grating 36 below which there is arranged an inclined plate El' connected through a conduit 38 with the vat 33, so that the h quidvwhich drips from the rinsed parts returns directly to vat 33. Protection after treatment is effected in vat 316 and the iinal drying (draining) oiigatiigl Silhsimilar to grating Sd, which is pro- (1 e w1 e same device the drippnguquid. for the recovery of The installation may include a hoistii paratus 40 capable of moving at a suitable llfigeillit above the various treating vats.
- the bottom of 9. the excavation 35 is advantageously inclined and coated with a waterproof material in order to permit the draining of theA liquids which may spill on same, and in order to facilitate cleaning.
- Amethod of freeing metals from rust, corrosion and the like which comprises immersing a metalvartcle in an electrolyticbath and passing an electric current between an anode in the bath and the article as a cathode, said bath consisting essentially of an aqueous solution of the following compounds:
- alkali metal metasilicate and aluminate 2 to 4 ora/gal.
- a method of freeing metals from rust, corrosion and the like which comprises immersing a metal article in an electrolytic bath and passing an electric current between an anode in the bath and the article as a cathode for a period up to about three and one-half hours, then reversing the direction of loW of current to render the article an anode for about one-lifth the period of time that the article served as the cathode, said bath consisting essentially of an aqueous solution of the following compounds:
- alkali metal metasilicate and aluminate 2 to 4 02./ gal.
- a method of freeing metals from rust, corrosion and the like which comprises immersing a metal article in an electrolytic bath and passing an electric current between an anode in the bath and the article as a cathode at a current density between about three and three and one-half amperes per square decimeter, said bath consisting essentially of an aqueous solution of the following compounds:
- alkali metal metasilicate and alumihate 2 to 4 02./ gal.
- a method of freeing metals from rust, corrosion and the like which comprises immersing a metal article in an electrolytic bath and passing an electric current between an anode in the bath and the article as a cathode for a period up to about three and one-half hours and at a current density between about three and three and one-half amperes per square decimeter, then reversing the direction of flow of current to render the article an anode for about one-fifth the period of-time that the varticle served as the cathode, said bath consisting essentially of an aqueous solution of the following compounds:
- yalkali metal metasilicate and aluminate 2 to 4 02./ gal.
- a method of freeing metals of surface deposits o-f rust, corrosion products .and other foreign substances comprising immersing a metallic article in ⁇ an electrolytic bath, passing an electric current between an anode and the article as a cath-ode at a current density'between about 3 and 31/2 amperes per square decimeter for a period of between about .two yand three and one-half h-ours, then reversing the current to render the Iarticle an anode for -a period of about one-fifth the duration of the period in which the article acted as a cathode, then removing the article from the bath and washing it, said bath consisting essentially of an aqueous solution in about the following proportions per gallon of water:
- Wetting agent of the class consisting of sulfated fatty alcohols and sulfonated oils 10.
- the following references are of record in the Alkali metal hydroxide lbs-- 2to31/2 le of this patent: Alkali metal Ghiqfidef1vn0h- 1 't0 8 UNITED STATES PATENTS Alkali metal yanide-- '.,OZn ⁇ 3110 12 5 Alkali metal uorie oz-.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Detergent Compositions (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR1022302T | 1947-06-06 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2615840A true US2615840A (en) | 1952-10-28 |
Family
ID=9577542
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US87261A Expired - Lifetime US2615840A (en) | 1947-06-06 | 1949-04-13 | Electrolytic method to remove rust |
Country Status (7)
Country | Link |
---|---|
US (1) | US2615840A (en, 2012) |
BE (1) | BE482434A (en, 2012) |
CH (1) | CH278602A (en, 2012) |
DE (1) | DE814231C (en, 2012) |
FR (1) | FR1022302A (en, 2012) |
GB (1) | GB693951A (en, 2012) |
LU (1) | LU29036A1 (en, 2012) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2801215A (en) * | 1956-02-08 | 1957-07-30 | Kolene Corp | Electrolytic ferrous metal cleaning |
US2830942A (en) * | 1957-05-24 | 1958-04-15 | Jr Robert H Elliott | Electrocleaner for brass |
US2934480A (en) * | 1953-08-14 | 1960-04-26 | Rohr Aircraft Corp | Titanium coating and method of forming same |
US2973307A (en) * | 1956-11-16 | 1961-02-28 | Lyon Inc | Method of treating stainless steel |
US3043758A (en) * | 1958-12-23 | 1962-07-10 | Ruthner Othmar | Process of electrolytically pickling alloy steels |
US3207683A (en) * | 1962-02-05 | 1965-09-21 | Coussinets Ste Indle | Process of electrolytic surface treatment of metals |
US3357905A (en) * | 1960-03-28 | 1967-12-12 | Cleveland Twist Drill Co | Electrolyte composition and method of electrolytically removing stock from workpiece |
US3900376A (en) * | 1972-11-08 | 1975-08-19 | Electricity Council | Cleaning of metal surfaces |
US4263120A (en) * | 1978-10-26 | 1981-04-21 | Norddeutsche Affinerie | Electrolytic cell for the recovery of nonferrous metals and improved anode therefor |
US6203691B1 (en) | 1998-09-18 | 2001-03-20 | Hoffman Industries International, Ltd. | Electrolytic cleaning of conductive bodies |
US6656606B1 (en) | 2000-08-17 | 2003-12-02 | The Westaim Corporation | Electroplated aluminum parts and process of production |
US20100326319A1 (en) * | 2009-06-25 | 2010-12-30 | Hyundai Motor Company | White rust inhibiting composition for aluminum parts |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE937209C (de) * | 1952-04-10 | 1955-12-29 | Richard Dr Springer | Verfahren zum elektrolytischen Entrosten, Entzundern und Bruenieren von Metallen in alkalischen Loesungen |
DE1012137B (de) * | 1955-01-31 | 1957-07-11 | Demag Elektrometallurgie Gmbh | Verfahren zum elektrolytischen Entzundern leicht gezunderter Eisenwerkstoffe in alkalischen Loesungen |
DE1109918B (de) * | 1955-02-01 | 1961-06-29 | Siemens Ag | Verfahren zum Sichtbarmachen von bis zur Oberflaeche durchgehenden Rissen oder Spalten in Metallstuecken |
DE1043008B (de) * | 1955-07-01 | 1958-11-06 | Othmar Ruthner | Verfahren und Vorrichtung zur elektrolytischen Entfernung von Stahlsandresten sandbestrahlter Oberflaechen von Metallbaendern |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1324317A (en) * | 1919-12-09 | Iron and steel | ||
US1528144A (en) * | 1921-02-15 | 1925-03-03 | Couesnon Jean | Process for cleaning and recovering soldered joints |
US1954473A (en) * | 1932-07-28 | 1934-04-10 | Bullard Co | Electrochemical process for removing scale and oxide from the surface of stainless steel |
US2371033A (en) * | 1941-12-24 | 1945-03-06 | Deshaw Zoltan | Process for loosening a corrosion frozen metal-to-metal joint |
-
0
- BE BE482434D patent/BE482434A/xx unknown
- LU LU29036D patent/LU29036A1/xx unknown
-
1947
- 1947-06-06 FR FR1022302D patent/FR1022302A/fr not_active Expired
-
1948
- 1948-05-14 CH CH278602D patent/CH278602A/fr unknown
-
1949
- 1949-01-01 DE DEP30282D patent/DE814231C/de not_active Expired
- 1949-04-13 US US87261A patent/US2615840A/en not_active Expired - Lifetime
-
1951
- 1951-08-17 GB GB19460/51A patent/GB693951A/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1324317A (en) * | 1919-12-09 | Iron and steel | ||
US1528144A (en) * | 1921-02-15 | 1925-03-03 | Couesnon Jean | Process for cleaning and recovering soldered joints |
US1954473A (en) * | 1932-07-28 | 1934-04-10 | Bullard Co | Electrochemical process for removing scale and oxide from the surface of stainless steel |
US2371033A (en) * | 1941-12-24 | 1945-03-06 | Deshaw Zoltan | Process for loosening a corrosion frozen metal-to-metal joint |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2934480A (en) * | 1953-08-14 | 1960-04-26 | Rohr Aircraft Corp | Titanium coating and method of forming same |
US2801215A (en) * | 1956-02-08 | 1957-07-30 | Kolene Corp | Electrolytic ferrous metal cleaning |
US2973307A (en) * | 1956-11-16 | 1961-02-28 | Lyon Inc | Method of treating stainless steel |
US2830942A (en) * | 1957-05-24 | 1958-04-15 | Jr Robert H Elliott | Electrocleaner for brass |
US3043758A (en) * | 1958-12-23 | 1962-07-10 | Ruthner Othmar | Process of electrolytically pickling alloy steels |
US3357905A (en) * | 1960-03-28 | 1967-12-12 | Cleveland Twist Drill Co | Electrolyte composition and method of electrolytically removing stock from workpiece |
US3207683A (en) * | 1962-02-05 | 1965-09-21 | Coussinets Ste Indle | Process of electrolytic surface treatment of metals |
US3900376A (en) * | 1972-11-08 | 1975-08-19 | Electricity Council | Cleaning of metal surfaces |
US4263120A (en) * | 1978-10-26 | 1981-04-21 | Norddeutsche Affinerie | Electrolytic cell for the recovery of nonferrous metals and improved anode therefor |
US6203691B1 (en) | 1998-09-18 | 2001-03-20 | Hoffman Industries International, Ltd. | Electrolytic cleaning of conductive bodies |
US6656606B1 (en) | 2000-08-17 | 2003-12-02 | The Westaim Corporation | Electroplated aluminum parts and process of production |
US6692630B2 (en) | 2000-08-17 | 2004-02-17 | The Westaim Corporation | Electroplated aluminum parts and process for production |
US20100326319A1 (en) * | 2009-06-25 | 2010-12-30 | Hyundai Motor Company | White rust inhibiting composition for aluminum parts |
US7988775B2 (en) * | 2009-06-25 | 2011-08-02 | Hyundai Motor Company | White rust inhibiting composition for aluminum parts |
Also Published As
Publication number | Publication date |
---|---|
FR1022302A (fr) | 1953-03-03 |
LU29036A1 (en, 2012) | |
BE482434A (en, 2012) | |
GB693951A (en) | 1953-07-08 |
DE814231C (de) | 1951-09-20 |
CH278602A (fr) | 1951-10-31 |
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