WO2006123489A1 - 六価クロムの抽出方法 - Google Patents
六価クロムの抽出方法 Download PDFInfo
- Publication number
- WO2006123489A1 WO2006123489A1 PCT/JP2006/307708 JP2006307708W WO2006123489A1 WO 2006123489 A1 WO2006123489 A1 WO 2006123489A1 JP 2006307708 W JP2006307708 W JP 2006307708W WO 2006123489 A1 WO2006123489 A1 WO 2006123489A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- hexavalent chromium
- chromium
- treated
- film
- reducing agent
- Prior art date
Links
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 title claims abstract description 214
- 238000000034 method Methods 0.000 title claims abstract description 60
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 69
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 64
- 239000011651 chromium Substances 0.000 claims abstract description 59
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 56
- 239000000463 material Substances 0.000 claims abstract description 52
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 claims abstract description 28
- 239000007788 liquid Substances 0.000 claims abstract description 8
- 239000008151 electrolyte solution Substances 0.000 claims description 35
- 238000011282 treatment Methods 0.000 claims description 21
- 238000007747 plating Methods 0.000 claims description 19
- 239000003792 electrolyte Substances 0.000 claims description 8
- 239000010419 fine particle Substances 0.000 claims description 4
- 238000000605 extraction Methods 0.000 abstract description 54
- 238000003912 environmental pollution Methods 0.000 abstract description 11
- 239000000284 extract Substances 0.000 abstract description 5
- 239000011248 coating agent Substances 0.000 abstract description 4
- 238000000576 coating method Methods 0.000 abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 29
- 238000010828 elution Methods 0.000 description 18
- 238000006243 chemical reaction Methods 0.000 description 17
- 238000006722 reduction reaction Methods 0.000 description 14
- 238000005868 electrolysis reaction Methods 0.000 description 13
- 230000009467 reduction Effects 0.000 description 13
- 238000012545 processing Methods 0.000 description 11
- 238000012360 testing method Methods 0.000 description 10
- 229910001430 chromium ion Inorganic materials 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 230000005855 radiation Effects 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000010298 pulverizing process Methods 0.000 description 5
- 239000002699 waste material Substances 0.000 description 5
- 239000002351 wastewater Substances 0.000 description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 239000011449 brick Substances 0.000 description 3
- 239000004020 conductor Substances 0.000 description 3
- -1 ferrous metals Chemical class 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920003002 synthetic resin Polymers 0.000 description 2
- 239000000057 synthetic resin Substances 0.000 description 2
- 208000019901 Anxiety disease Diseases 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000036506 anxiety Effects 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- NINOVVRCHXVOKB-UHFFFAOYSA-N dialuminum;dioxido(dioxo)chromium Chemical compound [Al+3].[Al+3].[O-][Cr]([O-])(=O)=O.[O-][Cr]([O-])(=O)=O.[O-][Cr]([O-])(=O)=O NINOVVRCHXVOKB-UHFFFAOYSA-N 0.000 description 1
- CMMUKUYEPRGBFB-UHFFFAOYSA-L dichromic acid Chemical compound O[Cr](=O)(=O)O[Cr](O)(=O)=O CMMUKUYEPRGBFB-UHFFFAOYSA-L 0.000 description 1
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000001962 electrophoresis Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000009700 powder processing Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- HRZFUMHJMZEROT-UHFFFAOYSA-L sodium disulfite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])(=O)=O HRZFUMHJMZEROT-UHFFFAOYSA-L 0.000 description 1
- 235000010262 sodium metabisulphite Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- POWFTOSLLWLEBN-UHFFFAOYSA-N tetrasodium;silicate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-][Si]([O-])([O-])[O-] POWFTOSLLWLEBN-UHFFFAOYSA-N 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000008016 vaporization Effects 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/86—Regeneration of coating baths
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09B—DISPOSAL OF SOLID WASTE NOT OTHERWISE PROVIDED FOR
- B09B3/00—Destroying solid waste or transforming solid waste into something useful or harmless
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G37/00—Compounds of chromium
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G37/00—Compounds of chromium
- C01G37/003—Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/30—Obtaining chromium, molybdenum or tungsten
- C22B34/32—Obtaining chromium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/006—Wet processes
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F3/00—Electrolytic etching or polishing
- C25F3/02—Etching
- C25F3/08—Etching of refractory metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B5/00—General methods of reducing to metals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Definitions
- the present invention reliably and inexpensively extracts harmful hexavalent chromium ions remaining on or inside a chrome plating or chromate film without requiring special and expensive equipment, and provides a hexavalent from a material to be treated.
- the present invention relates to a method for extracting hexavalent chromium that can prevent elution of chromium, safely use and dispose of remaining hexavalent chromium parts, and prevent environmental pollution and effects on the human body.
- Materials such as iron, non-ferrous metals, and synthetic resins are subjected to various surface treatments such as plating and chemical conversion treatment for the purpose of decoration and modification.
- chrome plating is widely used in the fields of automobiles, electronics, and electrical equipment as decorative chrome plating or industrial chrome plating because of its excellent decoration, corrosion resistance, and wear resistance.
- the chromium bath generally uses a large amount of chromic acid, that is, hexavalent chromium, as a source of chromium ions, sufficient measures for safety, hygiene, pollution, etc. are required and analyzed. It has been pointed out that hexavalent chromium remains in metallic chromium and chromate, which is eluted with rainwater and contaminates groundwater and the environment, and has a serious effect on the human body.
- the chromate treatment which is the chemical conversion treatment method, is used as a post-treatment for zinc-plated products and cadmium plating products, which is a material to be treated in a solution containing chromic acid or dichromic acid as a main component.
- a certain soak is immersed in the surface of the workpiece to form a protective film that is a thin passive film on the surface of the workpiece, but hexavalent chromium remaining on the surface of the workpiece is eluted by rainwater, causing serious environmental pollution and damage to the human body. It was pointed out that it had a significant impact.
- the reaction tank that adds a reducing agent to factory wastewater
- a precipitation tank that adds chromium to the wastewater introduced from the reaction tank to produce chromium precipitates.
- a measuring means for measuring the hexavalent chromium concentration in the waste water is provided, the amount of the reducing agent added is controlled based on the measured value of the means, and the chromium precipitate is metered, whereby the pipe line by the precipitate is used.
- the chromium removal method is intended for removal of hexavalent chromium in the waste water, it cannot cope with the extraction of hexavalent chromium remaining in the solid workpiece, and the reaction tank is a precipitation tank.
- the problem is that it requires measuring means and the equipment is expensive and requires a large installation space.
- a reducing agent is mixed with a hexavalent chromium-containing waste such as magchloro brick or chromada brick containing Mg (II), Cr (III) and harmful Cr (IV).
- a mixing step to form a compound heating the mixture in an oxygen-free atmosphere to reduce Mg (II) to metal magnesium, reducing and detoxifying Cr (IV), and a reduction treatment simultaneously with the reduction treatment.
- a method for treating hexavalent chromium-containing waste which includes a separation and recovery step of vaporizing and separating and recovering magnesium metal (see, for example, Patent Document 2).
- the processing method does not use magcro bricks as they are, but converts them into fine powder form.
- magcro bricks as they are, but converts them into fine powder form.
- the process of pulverization and pulverization equipment were required, and it took time and effort to dispose of the waste, and the process was complicated and complicated, resulting in poor productivity.
- Patent Document 1 Japanese Patent Laid-Open No. 2005-87988
- Patent Document 2 JP-A-11-169814
- the present invention solves such a problem and reliably and inexpensively extracts harmful hexavalent chromium remaining on or inside the chromium plating or chromate film without requiring special and expensive equipment.
- To provide a method for extracting hexavalent chromium that prevents elution of hexavalent chromium from the treated material enables safe use and disposal of the remaining hexavalent chromium, and prevents environmental pollution and effects on the human body. With the goal.
- the method for extracting hexavalent chromium of the present invention is similar to the method for extracting hexavalent chromium remaining in the material to be treated. Hexavalent chromium is extracted from the film by contacting with a reducing agent, so that hexavalent chromium can be easily and quickly extracted from a tangible material to be treated where hexavalent chromium remains.
- the material to be treated having the film in which the hexavalent chromium remains is brought into contact with the reducing agent while maintaining the original shape or the substantially original shape, and the solid material to be treated is obtained. It can be extracted in the state before processing basically without being pulverized or processed into powder, to realize easy and quick and inexpensive extraction processing, and to meet the mass production of extraction processing,
- a material to be treated having a film in which hexavalent chromium remains after chromate treatment or before disposal is brought into contact with the reducing agent, so that the chromate film or the chromium film is removed. It is suitable for extraction of hexavalent chromium remaining on the coated film, and it is suitable for extraction of both the production process and disposal process of the material to be treated, and properly treats the remaining hexavalent chromium parts for safe use.
- the material to be treated having a film in which the hexavalent chromium remains is immersed in a reducing agent, ultrasonic waves are emitted to the reducing agent, and the hexavalent by the reducing agent is emitted.
- Ultrasonic radiation treatment is used in combination with chromium extraction processing to extract hexavalent chromium quickly and accurately.
- the hexavalent chromium extraction method of the present invention comprises reducing the hexavalent chromium extracted from the film in which the hexavalent chromium remains to trivalent chromium via the reducing agent, and extracting the reducing agent to the hexavalent chromium. And the reduction of trivalent chromium, and the rational use of reducing agents.
- the method for extracting hexavalent chromium of the present invention is similar to the method for extracting hexavalent chromium remaining in the material to be treated.
- impress a positive or negative voltage on the material to be treated impress a positive or negative voltage on the material to be treated, extract hexavalent chromium from the coating, and forcibly and quickly extract the hexavalent chromium remaining on the material to be treated;
- the extraction process is improved in efficiency and extraction accuracy is improved.
- the material to be treated having a film in which the hexavalent chromium remains is brought into contact with the electrolyte while maintaining the original shape or substantially the original shape.
- the processing material can be extracted in the state prior to processing without being pulverized or processed into powder, so that extraction processing can be performed easily, quickly and inexpensively, and can be adapted to mass production of extraction processing. And then.
- a material to be treated having a film in which hexavalent chromium remains after chromium plating or before disposal is brought into contact with the electrolytic solution to form a chromate film.
- Is suitable for the extraction of hexavalent chromium remaining in the chromium plating film and is suitable for both the production process and the disposal process of the material to be treated, and appropriately treats the remaining hexavalent chromium parts. It is used safely and disposed of to prevent environmental pollution and impact on the human body, as well as being able to comply with the WEEE and RoHS directives and the regulations in Japan.
- the material to be treated having a film in which hexavalent chromium remains is immersed in an electrolytic solution, and ultrasonic waves are radiated to the electrolytic solution.
- Chrome Ultrasonic radiation treatment is used in combination with the extraction process to extract hexavalent chromium quickly and accurately.
- the hexavalent chromium extracted from the film in which the hexavalent chromium remains is moved into the electrolytic solution, and the hexavalent chromium is brought into contact with a reducing agent to contact the trivalent chromium.
- a reducing agent to contact the trivalent chromium.
- a material to be treated having a film in which hexavalent chromium remains is brought into contact with a liquid or fine particle reducing agent to extract hexavalent chromium from the film.
- hexavalent chromium can be easily and quickly extracted from a tangible material to be treated in which hexavalent chromium remains.
- the material to be treated having a film in which the hexavalent chromium remains is brought into contact with the reducing agent while maintaining the original or substantially original shape.
- extraction can be performed in a state prior to pulverization or powder processing, so that extraction can be easily and quickly performed at low cost, and the extraction process can be mass-produced.
- a material to be treated having a film in which hexavalent chromium remains after chromate treatment or before disposal is brought into contact with the reducing agent. It is suitable for extraction of hexavalent chromium remaining in the chromium plating film, and is suitable for the extraction process in both the production process and disposal process of the material to be treated, and properly treats the remaining hexavalent chromium parts, and its safety It can be used and disposed of in a safe manner to prevent environmental pollution and impact on the human body, as well as comply with the WEEE and RoHS directives and the regulations in Japan.
- the material to be treated having a film in which hexavalent chromium remains is immersed in a reducing agent, and ultrasonic waves are emitted to the reducing agent.
- Price It is possible to extract hexavalent chromium quickly and accurately by using ultrasonic radiation treatment in combination with ROM extraction.
- the hexavalent chromium extraction method of the present invention comprises reducing the hexavalent chromium extracted from the film in which the hexavalent chromium remains to trivalent chromium via the reducing agent, and the reducing agent is made of hexavalent chromium. It is used for both extraction and reduction to trivalent chromium so as to make reasonable use of the reducing agent.
- a material to be treated having a film in which hexavalent chromium remains is brought into contact with a liquid or fine particle electrolyte, and a positive or negative voltage is applied to the material to be treated. Then, since hexavalent chromium is extracted from the film, the hexavalent chromium remaining in the material to be treated can be forcibly and promptly extracted to improve the efficiency of the extraction process and improve the extraction accuracy.
- the material to be treated having a film in which the hexavalent chromium remains is brought into contact with the electrolytic solution while maintaining the original or substantially original shape.
- the processing material can be extracted in an unprocessed state basically without being pulverized or processed in powder form, realizing an easy, quick and inexpensive extraction process, and the effect of mass-producing the extraction process There is.
- the chromate film or It is suitable for extraction of hexavalent chromium remaining in the chromium plating film, and is suitable for the extraction process in both the production process and disposal process of the material to be treated, and properly treats the remaining hexavalent chromium parts, and its safety It can be used and disposed of in a safe manner to prevent environmental pollution and impact on the human body, as well as comply with the WEEE and RoHS directives and the regulations in Japan.
- the material to be treated having a film in which hexavalent chromium remains is immersed in an electrolytic solution, and ultrasonic waves are emitted to the electrolytic solution. It is possible to extract hexavalent chromium quickly and accurately by using ultrasonic radiation treatment together with the extraction process of chromium.
- the method for extracting hexavalent chromium of the present invention has a film in which the hexavalent chromium remains. Since positive or negative voltage is alternately applied to the material to be treated, hexavalent chromium can be extracted efficiently and accurately.
- the hexavalent chromium extracted from the film in which the hexavalent chromium remains is moved into the electrolytic solution, and the hexavalent chromium is reduced to trivalent chromium by contacting with the reducing agent. Therefore, extraction of hexavalent chromium and reduction to trivalent chromium can be performed rationally.
- FIG. 1 is a front view in which the present invention is applied to extraction of hexavalent chromium remaining in a chromate film.
- a chromate-treated part is immersed in a reducing agent to extract hexavalent chromium, and this is extracted with trivalent chromium. It shows the situation where
- FIG. 2 is a front view of the present invention applied to the extraction of hexavalent chromium remaining in a chrome-plated part.
- the chrome-plated part is immersed in an electrolytic solution for cathodic electrolysis, and the extracted hexavalent chromium is used as a reducing agent. It shows the situation of contact and reduction to trivalent chromium.
- Fig. 3 is a front view of the present invention applied to extraction of hexavalent chromium remaining in a chrome-plated part.
- the chrome-plated part is immersed in an electrolytic solution and subjected to anodic electrolysis. It shows the situation where it is reduced to trivalent chromium by contact with a reducing agent.
- Fig.4 The hexavalent chromium extraction method using the cathodic electrolysis method in Fig. 2 is combined with the ultrasonic radiation method to extract the hexavalent chromium remaining in the chrome-plated parts and reduce it to trivalent chromium. Indicates the situation.
- FIG. 5 Shows the situation in which the ultrasonic radiation method is used in combination with the hexavalent chromium extraction method in Fig. 1 to extract the hexavalent chromium remaining in the chromate film and reduce it to trivalent chromium.
- the surface of a workpiece is subjected to chromate treatment, and the workpiece surface is coated
- a 5% concentration solution is stored at normal temperature and normal pressure, and the reducing agent 2 is treated with a material to be treated (chromium) 3 made of iron or non-ferrous metal or synthetic resin whose surface is chromated. .
- the hexavalent chromium extraction process configured as described above is performed in the hexavalent chromium extraction process after the chromate process, or in the process step before disposal of the cake 3 used over time.
- a reaction bath 1 capable of containing the reducing agent 2 is prepared, and a suitable commercially available reducing agent 2 is diluted and accommodated in the reaction bath 1, and the reducing agent 2 is concentrated.
- 3 is basically immersed as it is, that is, without pulverizing or crushing, maintaining the original or substantially original shape.
- the workpiece 3 can be accommodated in the reducing agent 2 as it is, when hexavalent chromium is extracted after the chromate treatment, the workpiece 3 can be originally used without being deformed without being deformed. When extracting valent chromium, it can be extracted easily and quickly without the need for pulverization or powdering.
- FIG. 2 shows a second embodiment of the present invention.
- the electrolytic solution 4 is accommodated in the reaction bath 1 at room temperature and normal pressure.
- Commercially available alkaline electrolytic cleaning solution such as sodium carbonate, sodium carbonate, sodium orthosilicate, etc. is used after appropriately diluted with water.
- a switch 7 and a power source 8 are inserted into the conductor 6. ing.
- the cathode 3 of the power source 8 is connected to the battery 3, and the anode side of the power source 8 is connected to the anode plate 5.
- the surface of the steel plate 3 is chrome-plated, and the film is formed in a mat or porous shape with metallic chromium and chrome oxide, and remains on the plating surface or pore (hole). Hexavalent chromium and hexavalent chromium ions should be extracted!
- 9 is a reducing agent such as sodium pyrosulfite similar to that described above, which has been charged into the reaction bath 1, and the charging time is, for example, at the start of electrophoresis of hexavalent chromium ions or in advance in the reaction bath.
- a predetermined electrolytic solution 4 is accommodated in the reaction bath 1, and the anode 3 is immersed in the electrolyte 3 and the anode plate 5 is immersed in the electrolytic solution 4.
- the workpiece 3 is basically immersed in the same state as in the above-described embodiment, that is, without being crushed or crushed.
- the workpiece 3 can be accommodated in the electrolytic solution 4 as it is, when extracting hexavalent chromium after chrome plating, the workpiece 3 can be originally used without being deformed without being deformed, and before being discarded. When extracting hexavalent chromium, it can be extracted easily and quickly without the need for grinding.
- the hexavalent chromium remaining in the chromium plating has a negative charge, which is electrophoresed in the direction of the anode plate 5 having the opposite charge and diffuses into the electrolyte 4. .
- the hexavalent chromium is stirred by the generated hydrogen, and the uniform diffusion in the electrolytic solution 4 is promoted.
- the reducing agent 9 is introduced into the reaction bath 1, and the reducing agent 9 is brought into contact with the hexavalent chromium. Hexavalent chromium is reduced to trivalent chromium.
- FIG. 3 shows a third embodiment of the present invention.
- a voltage is applied to the work 3 and the electrode plate 5 in the opposite direction. In this way, a positive voltage is applied to the work 3, electrons are emitted from the power source 8 to the work 3, and water in the electrolytic solution 4 is oxidized to generate oxygen.
- the hexavalent chromium remaining in the chromium plating has a positive charge, which is electrophoresed in the direction of the oppositely charged electrode plate 5 and into the electrolytic solution 4.
- the hexavalent chromium is stirred by the generated oxygen to promote uniform diffusion in the electrolyte solution 4 and the hexavalent chromium is brought into contact with the reducing agent 9 to convert the hexavalent chromium into the trivalent chromium.
- the direction of the applied voltage to the workpiece 3 can be changed, and the ratio between the cathode energization and the cathode energization can be adjusted depending on the composition of the electrolyte solution 4 and the contamination state.
- an alternating voltage is applied to the workpiece 3 and the remaining hexavalent chromium ion charge is alternately charged, so that the hexavalent chromium ions are alternately electrophoresed to the anode or cathode side, and the hexavalent chromium ions Valent chromium is extracted accurately and reliably, and is reduced to trivalent chromium precisely and efficiently through the reducing agent 9.
- FIG. 4 shows a fourth embodiment of the present invention. This embodiment is located in the vicinity of the reaction bath 1 in the second or third embodiment or the application mode in which the alternating voltage is applied.
- An ultrasonic transmitter 10 is provided, and a plurality of ultrasonic transducers 11 that operate in conjunction with the transmitter 10 are installed on the bottom or side of the reaction bath 1.
- the inventor conducted the following elution or extraction experiment of hexavalent chromium. That is, prepare a plurality of chromium-plated aluminum foils 3 with the above-mentioned chromium as test pieces, heat one by immersing one of them in lOOOmL of pure water and boil the pure water. After concentration to 10 mL, the presence or absence of elution of hexavalent chromium in the pure water was measured, and a hexavalent chromium concentration of 2 ppm or more was measured.
- test piece was immersed in 10% strength reducing agent 9 for 3 minutes, then immersed in pure water of lOOOOmL and heated, and the pure water was boiled and concentrated to about lOOmL.
- pure water lOOOOmL
- a hexavalent chromium concentration of 2 ppm or more was measured.
- test piece was immersed in a reducing agent 9 having a concentration of 10%, and after radiating ultrasonic waves for 1 minute, the sample was immersed in pure water of lOOOOmL and heated. After boiling and concentrating to about 100 mL, the presence or absence of elution of hexavalent chromium in the pure water was measured, and a hexavalent chromium concentration of 2 ppm or more was measured.
- test piece was immersed in the electrolytic solution 4, cathodic electrolysis was performed for 1 minute, then immersed in pure water of lOOOmL and heated, the pure water was boiled and concentrated to about lOOmL, When the presence or absence of elution of hexavalent chromium in pure water was measured, the concentration of hexavalent chromium of 0.5 ppm was measured.
- test piece was immersed in the electrolytic solution 4, cathodic electrolysis was performed for 2 minutes, then immersed and heated in lOOOmL of pure water, the pure water was boiled and concentrated to about lOOmL, When the presence or absence of elution of hexavalent chromium in the pure water was measured, the concentration of hexavalent chromium of 0.3 ppm was measured.
- test piece is immersed in the electrolytic solution 4 and subjected to cathodic electrolysis for 3 minutes, and then immersed in pure water of lOOOOmL and heated, and the pure water is boiled and concentrated to about 10OOmL.
- pure water of lOOOOmL and heated, and the pure water is boiled and concentrated to about 10OOmL.
- a hexavalent chromium concentration of 0.05 ppm or less was measured.
- the substrate is immersed in 10 OOmL of pure water and heated, and the pure water is boiled to obtain about lOOmL. After concentration, the presence or absence of elution of hexavalent chromium in the pure water was measured, and a hexavalent chromium concentration of 0.05 ppm or less was measured.
- test piece is immersed in the electrolytic solution 4, and then subjected to cathodic electrolysis by irradiating with ultrasonic waves for 1 minute, then immersed in pure water of lOOOOmL and heated, and the pure water is heated. After boiling and concentrating to about 1 OOmL, the presence or absence of elution of hexavalent chromium in the pure water was measured, and a hexavalent chromium concentration of 0.1 lppm was measured.
- the elution concentration of hexavalent chromium is lowered by the cathodic electrolysis method shown in FIG. 2, but the effect is related to the cathodic electrolysis time, and is 0.5 ppm in 1 minute and 0 in 2 minutes. 3p pm, within 3 minutes, will be 0.05ppm or less, and these may be less than the legal regulation value of 0.5ppm. confirmed.
- the elution concentration of hexavalent chromium is not more than the legal regulation value of 0.5 ppm, which satisfies the legal regulation value, and It was confirmed that the extraction accuracy was improved.
- FIG. 5 shows a fifth embodiment of the present invention.
- This embodiment uses the ultrasonic radiation method in combination with the first embodiment, and is located in the vicinity of the reaction bath 1 containing the reducing agent 2.
- An ultrasonic transmitter 10 is provided, and a plurality of ultrasonic transducers 11 that operate in conjunction with the transmitter 10 are installed on the bottom or side of the reaction bath 1.
- the workpiece 3 is immersed in the reducing agent 2 or the electrolytic solution 4 and Z or the reducing agent 9, but the present invention is not limited thereto, and the reducing agent 2 or the electrolytic solution 4 and / or Alternatively, the reducing agent 9 can be formed into fine particles and brought into contact with them.
- the method for extracting hexavalent chromium of the present invention does not require special and expensive equipment, and reliably and reliably removes harmful hexavalent chromium remaining on the surface or inside of the chromium plating or chrome film. It is extracted at low cost, prevents elution of hexavalent chromium from the material to be treated, and enables safe use and disposal of the remaining hexavalent chromium parts, preventing environmental pollution and impact on the human body. is there.
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Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
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CN2006800007678A CN101018622B (zh) | 2005-05-18 | 2006-04-12 | 六价铬的抽除方法 |
EP20060731655 EP1882533B1 (en) | 2005-05-18 | 2006-04-12 | Method of extracting hexavalent chromium |
KR20077003173A KR100875823B1 (ko) | 2005-05-18 | 2006-04-12 | 6가크롬의 추출방법 |
DE200660012177 DE602006012177D1 (de) | 2005-05-18 | 2006-04-12 | Verfahren zur extraktion von sechswertigem chrom |
Applications Claiming Priority (2)
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JP2005-144858 | 2005-05-18 | ||
JP2005144858A JP4911920B2 (ja) | 2005-05-18 | 2005-05-18 | 六価クロムの抽出方法 |
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WO2006123489A1 true WO2006123489A1 (ja) | 2006-11-23 |
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PCT/JP2006/307708 WO2006123489A1 (ja) | 2005-05-18 | 2006-04-12 | 六価クロムの抽出方法 |
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US (1) | US8157982B2 (ja) |
EP (1) | EP1882533B1 (ja) |
JP (1) | JP4911920B2 (ja) |
KR (1) | KR100875823B1 (ja) |
CN (1) | CN101018622B (ja) |
AT (1) | ATE457208T1 (ja) |
DE (1) | DE602006012177D1 (ja) |
ES (1) | ES2341621T3 (ja) |
TW (1) | TWI327557B (ja) |
WO (1) | WO2006123489A1 (ja) |
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JP5457666B2 (ja) * | 2008-12-25 | 2014-04-02 | メルテックス株式会社 | クロムめっき膜の処理方法 |
CN114774129B (zh) * | 2022-03-29 | 2024-01-23 | 中冶南方都市环保工程技术股份有限公司 | 一种电动修复六价铬污染土壤用的电解液及电动修复方法 |
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JPS59162496A (ja) * | 1983-03-07 | 1984-09-13 | 株式会社日立製作所 | 酸化鉄皮膜の除去方法 |
JPS6324098A (ja) * | 1986-02-28 | 1988-02-01 | Chem Yamamoto:Kk | 合金鋼の溶接に伴なうスケ−ルの除去方法 |
JP2649625B2 (ja) * | 1991-12-10 | 1997-09-03 | 株式会社 ケミカル山本 | 含クロム合金鋼の電解琢磨用電解液 |
JP3687014B2 (ja) * | 1996-03-13 | 2005-08-24 | 株式会社ケミカル山本 | 含クロム鉱滓の処理方法 |
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JP4463278B2 (ja) * | 2004-09-28 | 2010-05-19 | 株式会社早川バルブ製作所 | 六価クロムフリー表面処理方法及び六価クロムフリー鉛含有銅系金属材 |
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- 2005-05-18 JP JP2005144858A patent/JP4911920B2/ja active Active
-
2006
- 2006-04-12 AT AT06731655T patent/ATE457208T1/de not_active IP Right Cessation
- 2006-04-12 US US11/666,268 patent/US8157982B2/en active Active
- 2006-04-12 WO PCT/JP2006/307708 patent/WO2006123489A1/ja active Application Filing
- 2006-04-12 ES ES06731655T patent/ES2341621T3/es active Active
- 2006-04-12 EP EP20060731655 patent/EP1882533B1/en not_active Not-in-force
- 2006-04-12 KR KR20077003173A patent/KR100875823B1/ko active IP Right Grant
- 2006-04-12 DE DE200660012177 patent/DE602006012177D1/de active Active
- 2006-04-12 CN CN2006800007678A patent/CN101018622B/zh not_active Expired - Fee Related
- 2006-05-11 TW TW095116675A patent/TWI327557B/zh active
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JP2003112143A (ja) | 2001-10-03 | 2003-04-15 | Toyota Motor Corp | 6価クロムを含む廃材の処理方法 |
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Also Published As
Publication number | Publication date |
---|---|
ATE457208T1 (de) | 2010-02-15 |
TWI327557B (en) | 2010-07-21 |
TW200700329A (en) | 2007-01-01 |
EP1882533B1 (en) | 2010-02-10 |
KR100875823B1 (ko) | 2008-12-26 |
JP2006320805A (ja) | 2006-11-30 |
US8157982B2 (en) | 2012-04-17 |
EP1882533A4 (en) | 2008-07-09 |
US20080087553A1 (en) | 2008-04-17 |
CN101018622B (zh) | 2011-06-29 |
ES2341621T3 (es) | 2010-06-23 |
KR20070061793A (ko) | 2007-06-14 |
CN101018622A (zh) | 2007-08-15 |
EP1882533A1 (en) | 2008-01-30 |
DE602006012177D1 (de) | 2010-03-25 |
JP4911920B2 (ja) | 2012-04-04 |
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