The treatment process of stainless steel chemical pigmentation aging liquid
Technical field
The present invention relates to a kind of stainless steel chemical pigmenting liquid, especially a kind of recycle treatment process that is used for stainless steel chemical pigmentation aging liquid.
Background technology
Color Stainless Steel is because of its unique advantages energy, has marketable value and more and more is subjected to people's favor.Among numerous preparation methods of relevant Color Stainless Steel, with acidic chemical painted (INCO) method because have bright in luster, wear resistant corrosion resistant good and be not subjected to characteristics such as the steel part shape influences and be most widely used.But, therefore greatly restricted applying of this method owing to contain more unmanageable high-concentration sulfuric acid and sexavalent chrome in its painted aging liquid.Treatment process to the existing chrome waste liquid of reporting can reduce following several:
(1) reduction method: because Cr
3+Toxicity is less relatively, so usually with the Cr in the waste liquid
6+Directly be reduced into Cr
3+, and then do next step processing.Wherein reduction mode comprises: chemical reduction method (seeing patent CN88106261.8, CN87105091.9, CN1263685C, CN1562510A, CN1073414A, CN1112608A, CN1003237B, JP54139261, JP55031439, JP2004223472, FR2865727, US2007051676, US2006016757, CA787884 etc.); Electrolytic reduction (seeing patent CN1255327C, CN86106414B, CN1763262A, JP2003260465 etc.); Biological reducing method (seeing patent CN1657430A, CN1733375A, CN1759942A, CN1644534A, JP2005177740, WO2007020588, KR20030005447 etc.) and water vapor transform reduction method (seeing patent CN1007134B) etc.But this method generally only is applicable to handles Cr
6+Alkalescence or neutral waste liquid that content is little are not fit to strongly-acid, high Cr
6+The processing of the aging liquid of the stainless steel coloring of content.
(2) precipitator method: with Cr
6+With PbCrO
4, BaCrO
4Or the precipitation forms of chromic sulfide is removed (seeing patent CN1166572C, CN1009730B, CN1039401A, CN1052102A, CN1526656A, CN1104384C, CN1597555A etc.).But this method can not be used for processing and contain sulfuric acid and chromic waste liquid simultaneously, because PbSO
4, BaSO
4Can separate out the final more difficult separation of gained precipitation mixture equally with precipitation forms.
(3) ion exchange method: with Cr
6+With CrO
4 2-Or Cr
2O
7 2-Form, after anti-strong acid scale resistance resin absorption collection, do next step processing (seeing patent CN1810683A, CN1762830A, JP52090164, EP0705793, US4036751, RU2291113, KR20040087440, KR20040034767 etc.) again.But this method generally is used to handle the less waste liquid of content of 6-valence Cr ions, and when containing the processing of the painted aging liquid of chromium for stainless high density, resin demand is very big, cost is high and the regeneration difficulty.
(4) extraction process: earlier isolate Cr in the waste liquid with extraction agent
6+, collect Cr with strippant again
6+, and then do next step processing (seeing patent CN1106361A, CN1220174A, JP2006320805, KR20050003079, KR100312274B etc.).This method generally also only is applicable to Cr
6+The waste liquid that content is low, and extraction agent and strippant consumption are big, efficient is low, operate loaded down with trivial details, the cost height.
As seen, aforesaid method all is not suitable for handling strongly-acid, high Cr
6+The stainless steel chemical pigmentation aging liquid of content.
Summary of the invention
The problem to be solved in the present invention is the pollution problem of chemical pigmentation aging liquid, the recovery and the cycling and reutilization problem thereof of useful component, its objective is the green treatment process that a kind of stainless steel chemical pigmentation aging liquid is provided.
The present invention at first adopts the evaporation partition method, isolates the solid mixture, trivalent chromium solutions (also containing nickelous and a small amount of ferric ion) and the distilled water that contain sexavalent chrome and trivalent iron salt from painted aging liquid; Adopt electrolytic oxidation then, the trivalent chromic ion in the above-mentioned trivalent chromium solutions is direct oxidation into sexavalent chrome at anode, simultaneously nickelous and a spot of ferric ion are enriched in negative electrode and separated.
The treatment process of stainless steel chemical pigmentation aging liquid of the present invention, its concrete grammar follow these steps to carry out:
(1) evaporation separating treatment:, isolate solid mixture, trivalent chromium solutions (also containing nickelous and a small amount of ferric ion) and the distilled water of sexavalent chrome and trivalent iron salt from aging liquid by with stainless steel chemical pigmentation aging liquid heating evaporation, cooling, crystallization and filtration.
The mode of its evaporation separating treatment has: atmospheric evaporation separates or reduction vaporization separates; Wherein the temperature of atmospheric evaporation is 95 ℃~140 ℃, and the temperature of reduction vaporization is 60 ℃~110 ℃; Treatment time is 30min~50min.
Solid mixture and the distilled water preparation that is used for new coloring liquid capable of circulation that its evaporation separating treatment reclaims because of trivalent iron salt solubleness is little, can remove by filter when the new coloring liquid of preparation.
(2) electrolytic oxidation is handled: the diluent of above-mentioned trivalent chromium solutions is placed electrolytic oxidation apparatus, carrying out electrolytic oxidation handles, at anode trivalent chromic ion is direct oxidation into sexavalent chrome, simultaneously bivalent nickel ion is enriched in catholyte, and remaining a small amount of ferric ion is reduced and is deposited on negative electrode.
Used anode material was during its electrolytic oxidation was handled: platinum, lead, plumbic oxide, titanium base platinum, ti-supported lead dioxide electric or graphite etc.; Used cathode material is: platinum, lead, plumbic oxide or graphite etc.; Used diaphragm material is: cationic exchange membrane or ceramic membrane etc.
The processing range that its electrolytic oxidation is handled is: make anolyte with the diluent that contains chromic liquid; Sulphuric acid soln with 5%~30% is made catholyte; By electrolytic oxidation, trivalent chromium is oxidized to sexavalent chrome, temperature is: 40 ℃~80 ℃, anodic current density is: 150~350A/m
2, the treatment time is looked Cr in the anolyte
3+Amount and annode area and deciding.
Anolyte after its electrolytic oxidation is handled can be directly used in the preparation of new coloring liquid; Catholyte after electrolytic oxidation is handled can repeatedly circulate and be used to prepare new anolyte, Ni in catholyte
2+Concentration when higher, can further reclaim nickel by chemistry or electrochemical reducing.
The treatment process of stainless steel chemical pigmentation aging liquid of the present invention is compared with traditional chrome waste liquid treatment process, has (1) this technology and can be directly used in processing strongly-acid and high density Cr
6+Aging liquid and other waste liquid are realized separating and recovery of chromium and vitriolic recycle and nickel and iron; (2) sexavalent chrome that reclaims in the evaporating concentration process (containing trivalent iron salt) and the distilled water preparation that is used for new coloring liquid all capable of circulation, little because of trivalent iron salt solubleness simultaneously, directly filtering when the new coloring liquid of preparation; (3) in the electrolytic acid cleaning oxydation process, be oxidized to the chromic while at trivalent chromic ion, remaining ferric ion is deposited on negative electrode, and bivalent nickel ion mainly is enriched in the catholyte; (4) anolyte behind the electrolytic oxidation can be directly used in the preparation of new coloring liquid; Catholyte can repeatedly circulate and be used to prepare new anolyte, when bivalent nickel ion concentration is higher in the catholyte, can further reclaim nickel by chemistry or electrochemical reducing; (5) this technology also has easy and simple to handle, mild condition, equipment is simple and characteristics such as zero release, has remedied the deficiency of INCO chemical coloring process preferably, and perfect whole technology has industrial prospect.
Description of drawings
Fig. 1 is a process flow sheet of the present invention
Fig. 2 is an electrolytic oxidation apparatus synoptic diagram of the present invention
Among the figure: 1: the stainless steel coloring liquid 2 that wears out: evaporation separating treatment 3: distilled water 4: chromic anhybride and trivalent iron salt 5: the aging liquid 6 of residue: electrolytic oxidation processes 7: anolyte 8 after the oxidation: catholyte 9 after the oxidation: catholyte repeatedly is cycled to used in the new anolyte 10 of preparation: further by chemistry or electrochemical reducing recovery nickel 11: power supply 12: ammeter 13: anode 14: anolyte 15: agitator 16: barrier film 17: catholyte 18: negative electrode
Embodiment
The present invention further describes as follows in conjunction with the accompanying drawings with embodiment:
Embodiment 1
The first step, evaporation separating treatment: get the 160mL stainless steel chemical pigmentation aging liquid, place 250mL to be assembled with the there-necked flask of agitator, thermometer and prolong.When stirring down with electric mantle direct heating to 95 ℃, solution comes to life subsequently temperature-stable at 98 ℃.Behind about 40min, temperature slowly rises to 140 ℃, and this moment, substantially anhydrous drip went out.Stop heating, after leaving standstill cool to room temperature, ice bath cools off 4h~5h again, suction filtration, with solid dry 5h~6h under 90 ℃~100 ℃, can get the sorrel particulate solid mixture of 28.7g chromic trioxide and trivalent iron salt, it is capable of circulation to be used for the preparation (this moment is because of chromic trioxide and trivalent iron salt dissolubility difference, but filtering trivalent iron salt) of new coloring liquid.It is stand-by to collect the thick trivalent chromium solutions of deep green (also containing nickelous and a small amount of ferric ion) simultaneously.
In second step, electrolytic oxidation is handled: get the trivalent chromium solutions of 70mL after the first step is handled, place electrolytic oxidation apparatus as anolyte after diluting one times, catholyte is made barrier film with 30% sulphuric acid soln with the tetrafluoroethylene cationic exchange membrane, and platinized platinum is made anode, stereotype is made negative electrode, connects circuit.Stir heating in water bath down, be warmed up to 80 ℃ after, connect power supply, the control anodic current density is 350A/m
2, electrolytic oxidation is handled 6h, during should suitably add less water.After reaction finishes, get the garnet anolyte, record Cr
6+Content 52.08g/L, Cr
3+Content 0.89g/L, Fe
3+Content 0.27g/L, Ni
2+Content 0.31g/L, transformation efficiency 72.37%, current efficiency 94.19%.As seen, this moment, this anolyte can be directly used in the preparation of new coloring liquid.In addition, the preparation that is used for next time new anolyte capable of circulation of the catholyte after the oxidation.
Embodiment 2
The first step evaporation separating treatment: get the aging liquid of 160mL stainless steel coloring, place 250mL to be assembled with the there-necked flask of agitator, thermometer and prolong.Decompression (the about 0.01MPa of vacuum tightness) is stirred down, and when being warmed up to 60 ℃ with oil bath, solution comes to life, and temperature-stable is at 72 ℃ subsequently.Behind about 30min, temperature slowly rises to 107 ℃, and this moment, substantially anhydrous drip went out.Stop heating, leave standstill cool to room temperature, ice bath cools off 4h~5h again, suction filtration, with solid dry 5h~6h under 90 ℃~100 ℃, can get the sorrel granular mixture of 27.9g chromic trioxide and trivalent iron salt, it is capable of circulation to be used for the preparation (this moment is because of chromic trioxide and trivalent iron salt dissolubility difference, but filtering trivalent iron salt) of new coloring liquid.It is stand-by to collect the thick trivalent chromium solutions of deep green (also containing nickelous and a small amount of ferric ion) simultaneously.
The second one-step electrolysis oxide treatment: get the trivalent chromium solutions of 50mL after the first step is handled, place electrolytic oxidation apparatus as anolyte after the dilution twice, catholyte is with 20% sulphuric acid soln, make barrier film with the A4 ceramic membrane, titanium base platinized electrode is made anode, and graphite is made negative electrode, connects circuit.After stirring down warming-in-water to 65 ℃, connect power supply, the control anodic current density is 300A/m
2, electrolytic oxidation is handled 4h, during should suitably add some water.After reaction finishes, get the garnet anolyte, record Cr
6+Content 32.08g/L, Cr
3+Content 0.63g/L, Fe
3+Content 0.16g/L, Ni
2+Content 0.24g/L, transformation efficiency 75.84%, current efficiency 91.43%.This anode liquid can be directly used in the preparation of new coloring liquid, and the catholyte after the oxidation is capable of circulation to be used for the preparation of new anolyte next time
Embodiment 3
The first step evaporation separating treatment is with embodiment 1.
The second one-step electrolysis oxide treatment: get the trivalent chromium solutions of 35mL after the first step is handled, place electrolytic oxidation apparatus as anolyte after diluting three times, catholyte is with 10% sulphuric acid soln, make barrier film with the common cation exchange membrane, ti-supported lead dioxide electric pole is made anode, stereotype is made negative electrode, connects circuit.After stirring down warming-in-water to 50 ℃, connect power supply, the control anodic current density is 250A/m
2, electrolytic oxidation is handled 2.5h, during should suitably add some water.After reaction finishes, get the garnet anolyte, record Cr
6+Content 26.13g/L, Cr
3+Content 0.51g/L, Fe
3+Content 0.09g/L, Ni
2+Content 0.19g/L, transformation efficiency 78.64%, current efficiency 96.36%.This moment, this anolyte can also be directly used in the preparation of new coloring liquid, and the catholyte after the oxidation is capable of circulation to be used for the preparation of new anolyte next time.
Embodiment 4
The first step evaporation separating treatment is with embodiment 2.
The second one-step electrolysis oxide treatment: get the trivalent chromium solutions of 30mL after the first step is handled, place electrolytic oxidation apparatus as anolyte after diluting four times, catholyte is with 5% sulphuric acid soln, with A
3Ceramic membrane is made barrier film, and lead dioxide electrode is made anode, and graphite is made negative electrode, connects circuit.After stirring down warming-in-water to 40 ℃, connect power supply, the control anodic current density is 200A/m
2, electrolytic oxidation is handled 2h, during should suitably add some water.After reaction finishes, get bolarious anolyte, record Cr
6+Content 21.09g/L, Cr
3+Content 0.47g/L, Fe
3+Content 0.05g/L, Ni
2+Content 0.11g/L, transformation efficiency 81.08%, current efficiency 97.34%.This moment, this anolyte can be directly used in the preparation of new coloring liquid, and the catholyte after the oxidation is capable of circulation to be used for the preparation of new anolyte next time.