CN111304444A - Treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge - Google Patents
Treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge Download PDFInfo
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- 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
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/06—Preparation of sulfates by double decomposition
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/16—Purification
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/18—Dehydration
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- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
- C14C3/00—Tanning; Compositions for tanning
- C14C3/02—Chemical tanning
- C14C3/04—Mineral tanning
- C14C3/06—Mineral tanning using chromium compounds
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- 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
- C22B15/00—Obtaining copper
- C22B15/0063—Hydrometallurgy
- C22B15/0084—Treating solutions
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- 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
- C22B19/00—Obtaining zinc or zinc oxide
- C22B19/20—Obtaining zinc otherwise than by distilling
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- 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
- C22B19/00—Obtaining zinc or zinc oxide
- C22B19/30—Obtaining zinc or zinc oxide from metallic residues or scraps
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- 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
- C22B23/00—Obtaining nickel or cobalt
- C22B23/04—Obtaining nickel or cobalt by wet processes
- C22B23/0453—Treatment or purification of solutions, e.g. obtained by leaching
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- 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
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- 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
Abstract
The invention provides a treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge, belonging to the field of resource utilization of industrial waste liquid. Dissolving the chromium-containing sludge in acid, and then removing copper and iron in the solution by electrolysis and extraction methods to obtain a ferrous sulfate solution; neutralizing the obtained impurity-removed solution, and filtering to obtain sludge 1 and a high-salt solution; adding alkali liquor into the obtained high-salt solution, adding the obtained ferrous sulfate solution, and filtering to obtain a ferrite product and an impurity-removed sulfate solution; alkaline leaching the sludge 1, and putting the sludge into a reduction pool of a diaphragm electrolytic cell to obtain sludge 2 and a zinc-containing solution; putting the sludge 2 into an oxidation tank of a diaphragm electrolytic cell, dissolving the sludge with alkali liquor, and carrying out electrolytic filtration and washing to obtain a nickel sludge product and a zinc-containing hexavalent chromium solution; adding acid into the zinc-containing hexavalent chromium solution, neutralizing, filtering and washing to obtain chromium-containing zinc mud and a hexavalent chromium solution; adding acid and reducing agent into the obtained chromium solution to obtain trivalent chromium solution, and adding alkali to obtain the chrome tanning agent product. The invention realizes the resource utilization of the chromium-containing sludge and does not generate three wastes.
Description
Technical Field
The invention belongs to the field of resource utilization of industrial waste liquid, and particularly relates to a treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge.
Background
With the development of electroplating industry, the yield of electroplating wastewater and sludge is increased, and the treatment difficulty is higher than that of other sludge due to the high toxicity of the chromium-containing sludge, the treatment difficulty and the high requirement. The chromium-containing sludge also contains other heavy metal impurities, particularly zinc and aluminum impurities, and the impurities are difficult to directly distinguish through alkaline leaching because the impurities are all double oxides. The common method is to add an oxidant in the alkaline leaching process to oxidize trivalent chromium into hexavalent chromium, simultaneously leach aluminum and zinc, and remove aluminum and zinc in the chromium product by a method of adjusting pH to neutralize and precipitate. However, in the process, a large amount of neutralized aluminum mud/zinc mud is generated, and hexavalent chromium in the solution can be carried by the neutralized mud, so that the disposal cost is increased, and meanwhile, great potential safety hazards are brought to subsequent treatment.
In the aspect of treatment of the neutralized mud, acid is often added to dissolve the neutralized mud, and then a reducing agent is added to reduce hexavalent chromium carried in the mud into trivalent chromium. The chromium content in the neutralized mud can also be reduced by water washing, electrodialysis and other technologies. But this is still a tail treatment of the neutralized sludge and does not fundamentally achieve the separation of aluminum/zinc and chromium.
For example, chromium-containing sludge is calcined at high temperature to enable chromium elements to exist in the form of chromium sesquioxide which is not leached by alkali, then the calcined sludge is subjected to alkali leaching to leach aluminum/zinc, and then the sludge without aluminum/zinc is calcined, so that the yield of the neutralized sludge can be greatly reduced, and further the cost and risk of disposing the neutralized sludge are reduced. The process is a dry method-wet method-dry method, the chromium calcined subsequently still needs to be separated by a wet method, the steps are complicated, and the requirement on supporting facilities is high. This process must be accomplished with both wet and dry conditions.
Patent CN1255327C provides an economical and feasible method for electrolyzing hexavalent chromium in industrial wastewater, which directly performs electrolysis under alkaline conditions, uses insoluble lead-antimony alloy as an anode and an iron plate as a cathode, and passes direct current in an open diaphragm-free electrolytic cell to reduce hexavalent chromium into trivalent chromium. Acid and alkali are not needed to be added for adjustment before and after electrolysis, so that the process is simplified, the acid and alkali consumption is reduced, the transportation cost is correspondingly reduced, and the operation is also simplified.
Disclosure of Invention
Aiming at the problems in the prior art, the applicant of the invention provides a treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge. The chromium-containing sludge containing various heavy metal impurities is processed into products such as copper simple substance, iron solution, chrome tanning agent, zinc, nickel mud and the like by processing the chromium-containing sludge, so that the resource utilization of the chromium-containing sludge is realized, the processing process is safe and environment-friendly, and no three wastes are generated.
The method analyzes the content of the components in the chromium-containing sludge, further dilutes the chromium-containing sludge, and obtains products such as basic chromium sulfate, metal simple substances, metal mud and the like after ammonium salt and ammonia water treatment, alkali treatment and acid treatment. Especially the combination of alkaline reduction and alkaline oxidation, so that the yield of the neutralized mud is reduced by more than 90 percent, better economic benefit can be obtained, and the disposal risk can be reduced. The invention is applied to the treatment and recovery process of the chromium-containing sludge generated in a plurality of industries such as steel, electroplating, tanning and the like, and achieves good effects of pollution control and resource recovery.
The technical scheme of the invention is as follows:
a treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge comprises the following steps:
(1) adding sulfuric acid into the chromium-containing sludge to completely dissolve the chromium-containing sludge;
(2) carrying out electrolytic copper removal on the solution obtained in the step (1), then removing iron in the solution by using an extraction method to obtain an impurity-removed solution and an iron extract, carrying out back extraction on the obtained iron extract to obtain a ferric ion solution, and treating with iron powder to obtain a ferrous sulfate solution;
(3) performing alkali washing on the impurity-removed solution obtained in the step (2), adjusting the pH value of the solution to 7-10, and filtering to obtain sludge 1 and a high-salt solution;
(4) adding alkali liquor into the high-salt solution obtained in the step (3), adjusting the pH value of the solution to 10-12, adding the ferrous sulfate solution obtained in the step (2), and filtering after the reaction is finished to obtain a ferrite product and an impurity-removed sulfate solution;
(5) further performing alkali washing on the sludge 1 obtained in the step (3), adjusting the pH value of the sludge to be more than 14, and putting the sludge into a reduction pool of a diaphragm electrolytic cell to obtain sludge 2 and a zinc-containing solution;
(6) putting the sludge 2 obtained in the step (5) into an oxidation tank of a diaphragm electrolytic cell, continuously dissolving the sludge with alkali liquor, filtering and washing the sludge after electrolytic oxidation to obtain a nickel sludge product and a zinc-containing hexavalent chromium solution;
(7) adding a sulfuric acid solution into the zinc-containing hexavalent chromium solution obtained in the step (6), adjusting the pH value of the solution to be 6-7, neutralizing, filtering and washing to obtain a zinc mud product and a hexavalent chromium solution;
(8) adding a strong acid and a reducing agent into the hexavalent chromium solution obtained in the step (7) to reduce the hexavalent chromium into trivalent chromium;
(9) and (4) adding strong base into the trivalent chromium solution obtained in the step (8), adjusting the alkalinity of the solution to be 32-34%, and drying the obtained solution to obtain a chromium tanning agent product.
In the step (1), the mass concentration of the sulfuric acid is 10-40%, and the mass ratio of the acid addition amount to the sludge amount is 1: 1-4: 1.
in the step (2), the extractant is one of P204 or N235, and a sulfuric acid solution is used for back extraction, wherein the concentration of the sulfuric acid solution is 5-20 wt%.
The alkali used in the steps (3), (4) and (5) is at least one of sodium hydroxide solution, potassium hydroxide solution or ammonia water, and the mass concentration of the alkali is 5-20%.
The reaction conditions in the step (4) are as follows: the reaction temperature is 70-90 ℃, and the reaction time is 0.5-2 h.
In the steps (5) and (6), the cathode of the diaphragm electrolytic cell is a titanium plate, the anode of the diaphragm electrolytic cell is titanium iridium ruthenium, and the voltage between the plates is 24V.
The temperature of the solution in the step (5) needs to be kept between 5 and 20 ℃, and the electrolysis time is 8 to 12 hours; and (4) keeping the temperature of the solution in the step (6) between 60 and 95 ℃, and electrolyzing for 8 to 12 hours.
In the step (8), the strong acid is sulfuric acid, and the mass concentration of the strong acid is 1-15%; the reducing agent is at least one of sodium bisulfite, sodium sulfite or potassium sulfite, and the mass concentration of the reducing agent is 1-5%.
And (3) the strong base in the step (9) is at least one of a sodium hydroxide solution, a potassium hydroxide solution, a sodium carbonate solution or a sodium bicarbonate solution, and the mass concentration of the strong base is 30-40%.
The chromium-containing sludge comprises 3-20% of chromium, 2-15% of zinc ions, 1-5% of Cu, 1-5% of Fe and 1-5% of Ni in percentage by mass.
The beneficial technical effects of the invention are as follows:
(1) through the selective alkaline leaching reduction-oxidation process, the yield of the neutralized chromium-containing zinc mud is greatly reduced, the content of chromium in a zinc product is reduced, and the method has good effects on secondary waste reduction and product upgrading. The problems of zinc and chromium separation in the invention are as follows: the method utilizes that trivalent chromium is easily oxidized into hexavalent chromium under alkalinity, and can be realized by adding an oxidant or oxidation potential, but firstly, the trivalent chromium is dissolved into an alkali liquor, and is easily oxidized, so that the separation is not easy when zinc and chromium are conventionally separated, if zinc is leached out by alkaline leaching, the interior of the zinc contains more chromium, and part of the zinc exists in the form of hexavalent chromium, so that the recovery difficulty of zinc is improved, if the chromium is leached out by oxidizing, the interior of the chromium contains a large amount of zinc, or the separation of the zinc and the chromium cannot be realized, and the method for solving the problem is as follows: when zinc is leached firstly, a reducing agent is added or a reduction potential is added for electrolytic reduction, so that the leaching of chromium can be greatly limited during the zinc leaching, the chromium content can be reduced to be within 2ppm from hundreds of ppm even can be undetected, a pure zinc product is finally obtained, then the chromium is extracted by alkaline leaching oxidation, and the zinc in the chromium can be reduced by more than 95 percent, so that the respective extraction of zinc and chromium can be well realized.
(2) Through the treatment of the diaphragm electrolytic cell, the two steps of reduction and oxidation in the process are realized, and the use of the oxidant and the reductant is reduced to the maximum extent.
(3) By the process, various heavy metals in the chromium-containing sludge can be separated cleanly, products such as copper, ferrite, chrome tanning agent, nickel mud, zinc mud and the like are obtained, and resource utilization of the chromium-containing sludge is realized.
(4) The process of the invention realizes the separation of the chromium and zinc double oxides and has better benefit.
Drawings
FIG. 1 is a schematic view of the present invention.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings and examples.
Example 1
The chromium-containing sludge of a certain plant area comprises 20% of chromium, 10% of zinc, 5% of Cu, 1% of Fe and 1% of Ni. 100g of chromium-containing sludge is added with sulfuric acid to be completely dissolved, the acid concentration is 10 percent, and the acid adding amount is 400 g. Electrolyzing the acid-dissolved solution for 24h to remove copper in the solution, wherein the concentration of copper ions in the solution is 37mg/m34.8g of copper simple substance is recovered. Removing iron in the solution by extraction method, wherein the concentration of iron ions in the solution is 49mg/m3. And (4) obtaining a ferric iron solution after back extraction of the iron extract, and obtaining a ferrous sulfate solution after reduction by using excessive reduced iron powder. Adding 10% sodium hydroxide into the solution, and adjusting pH toAnd 9, filtering to obtain sludge and high-salt solution. Adding ferrous sulfate into the high-salt solution, adjusting the pH value to 11, heating to 70 ℃, keeping for 0.5h, filtering to obtain 2.1g of ferrite, and distilling the high-salt solution to obtain a sodium sulfate product. Adding 10% sodium hydroxide to further alkali wash the sludge, adjusting pH to be more than 14(2.5mol/L hydroxyl concentration), placing the sludge into a reduction cell of a diaphragm electrolytic cell, maintaining the temperature at 10 ℃, and electrolyzing for 8 hours to obtain a zinc solution and 88g of sludge, wherein the chromium content in the zinc solution is 347mg/m3. The zinc solution is acidified to obtain 14g of zinc mud. Adding 4 times of 20% sodium hydroxide into the sludge, pumping into an oxidation tank of a diaphragm electrolytic cell, maintaining the temperature at 80 ℃, electrolyzing for 8h, filtering, and washing with water to obtain 1.5g of nickel mud and a zinc-chromium-containing solution. Adding a sulfuric acid solution into the solution, adjusting the pH value to 7, and filtering and washing to obtain 1.1g of zinc mud product and hexavalent chromium solution. And adding a 10% sulfuric acid solution into the solution, adding a 5% sodium bisulfite solution into the solution, and reducing hexavalent chromium into trivalent chromium to obtain 61g of the chromium tanning agent.
Comparative example: in order to embody the advantages of alkaline leaching reduction-oxidation, alkaline leaching oxidation and alkaline leaching-oxidation experiments are carried out.
The alkaline leaching oxidation is to add 20 percent sodium hydroxide in an amount which is 4 times that of the sludge without copper and iron into the sludge, then the sludge is put into an oxidation tank of a diaphragm electrolytic cell, the temperature is kept at 80 ℃, the sludge is electrolyzed for 8 hours and then filtered, and the nickel sludge and the zinc-chromium-containing solution are obtained after the sludge is washed by water. Adding acid to neutralize the zinc-chromium-containing solution to obtain chromium-zinc-containing mud (neutralized mud) and zinc-chromium-removing solution.
Comparative example: the alkaline leaching-oxidation is to add 10% of sodium hydroxide into the sludge without copper and iron to further carry out alkaline washing on the sludge, adjust the pH value to be more than 14(2.5mol/L of hydroxide concentration), keep the temperature at 10 ℃, react for 8 hours to obtain zinc solution and sludge, add 4 times of 20% of sodium hydroxide into the sludge, pump the sludge into an oxidation cell of a diaphragm electrolytic cell, keep the temperature at 80 ℃, electrolyze for 8 hours, filter the sludge, and wash the sludge with water to obtain nickel mud and zinc-chromium-containing solution. Adding acid to neutralize the zinc-chromium-containing solution to obtain chromium-zinc-containing mud (neutralized mud) and zinc-chromium-removing solution.
TABLE 1
As can be seen from Table 1, about 17g of neutralized sludge was produced by alkaline leaching oxidation, the neutralized sludge was composed of zinc hydroxide containing a large amount of hexavalent chromium, and the yield of neutralized sludge was greatly reduced by first extracting zinc by alkaline leaching and then extracting chromium by oxidation. But the chromium content in the zinc solution obtained by direct alkaline leaching is still higher, so that the chromium content in the subsequent zinc product is higher. In contrast, using alkaline leaching reduction-oxidation, it is possible to reduce the yield of neutralized sludge to 6.47% of alkaline leaching oxidation, while removing 95.92% of the chromium in the zinc solution, resulting in a reduction of the chromium content in the zinc product from 0.12% to 0.003%.
Example 2
The chromium-containing sludge of a certain plant area comprises 15% of chromium, 3% of zinc, 6% of Cu, 2% of Fe and 2% of Ni. 100g of chromium-containing sludge is completely dissolved by adding sulfuric acid, the acid concentration is 40 percent, and the acid adding amount is 100 g. Electrolyzing the acid-dissolved solution for 24h to remove copper in the solution, wherein the concentration of copper ions in the solution is 42mg/m35.9g of copper simple substance is recovered. Removing iron in the solution by extraction method, wherein the concentration of iron ions in the solution is 21mg/m3. And (4) obtaining a ferric iron solution after back extraction of the iron extract, and obtaining a ferrous sulfate solution after reduction by using excessive reduced iron powder. Adding 10% sodium hydroxide into the solution, adjusting the pH value to 10, and filtering to obtain sludge and high-salt solution. Adding ferrous sulfate into the high-salt solution, adjusting the pH value to 12, heating to 90 ℃, keeping for 2h, filtering to obtain 4.3g of ferrite, and distilling the high-salt solution to obtain a sodium sulfate product. Adding 20% sodium hydroxide to further carry out alkaline washing on the sludge, adjusting the pH value to be more than 14(3.5mol/L hydroxyl concentration), putting the sludge into a reduction tank of a diaphragm electrolytic cell, maintaining the temperature at 20 ℃, and electrolyzing for 8 hours to obtain a zinc solution and 74g of sludge, wherein the chromium content in the zinc solution is 871mg/m3.4g of zinc mud is obtained after the zinc solution is acidified. Adding 4 times of 20% sodium hydroxide into the sludge, pumping into an oxidation tank of a diaphragm electrolytic cell, maintaining the temperature at 90 ℃, electrolyzing for 8h, filtering, and washing with water to obtain 3.4g of nickel mud and a zinc-chromium-containing solution. Adding sulfuric acid solution into the solution, adjusting pH to 6, filtering and washing to obtain zinc mud product 0.8g and hexavalent chromium solutionAnd (4) liquid. And adding a 10% sulfuric acid solution into the solution, adding a 5% sodium bisulfite solution into the solution, and reducing hexavalent chromium into trivalent chromium to obtain 47g of the chromium tanning agent.
TABLE 2
As can be seen from Table 2, about 5.4g of neutralized sludge was produced by alkaline leaching oxidation, the neutralized sludge was composed of zinc hydroxide containing a large amount of hexavalent chromium, and the yield of neutralized sludge was greatly reduced by first extracting zinc by alkaline leaching and then extracting chromium by oxidation. But the chromium content in the zinc solution obtained by direct alkaline leaching is still higher, so that the chromium content in the subsequent zinc product is higher. In contrast, using alkaline leaching reduction-oxidation, the yield of neutralized sludge can be reduced to 85.19% of alkaline leaching oxidation, and 93.95% of chromium in the zinc solution is removed, so that the chromium content in the zinc product is reduced from 0.31% to 0.007%.
Example 3
The chromium-containing sludge of a certain plant area comprises 5% of chromium, 18% of zinc, 4% of Cu, 1% of Fe and 1% of Ni. 100g of chromium-containing sludge is added with sulfuric acid to be completely dissolved, the acid concentration is 20 percent, and the acid adding amount is 200 g. Electrolyzing the acid-dissolved solution for 24h to remove copper in the solution, wherein the concentration of copper ions in the solution is 16mg/m33.8g of copper simple substance is recovered. Removing iron in the solution by extraction method, wherein the concentration of iron ions in the solution is 24mg/m3. And (4) obtaining a ferric iron solution after back extraction of the iron extract, and obtaining a ferrous sulfate solution after reduction by using excessive reduced iron powder. Adding 5% sodium hydroxide into the solution, adjusting the pH value to 7, and filtering to obtain sludge and high-salt solution. Adding ferrous sulfate into the high-salt solution, adjusting the pH value to 10, heating to 70 ℃, keeping the temperature for 1h, filtering to obtain 1.7g of ferrite, and distilling the high-salt solution to obtain a sodium sulfate product. Adding 10% sodium hydroxide to further alkali wash the sludge, adjusting the pH value to be more than 14(1.5mol/L hydroxyl concentration), putting the sludge into a reduction tank of a diaphragm electrolytic cell, keeping the temperature at 5 ℃, and electrolyzing for 8 hours to obtain a zinc solution and 53g sludge, wherein the chromium content in the zinc solution is less than 1000mg/m3. Acid zinc solution22g of zinc mud is obtained after the zinc is transformed. Adding 4 times of 20% sodium hydroxide into the sludge, pumping into an oxidation tank of a diaphragm electrolytic cell, maintaining the temperature at 70 ℃, electrolyzing for 8 hours, filtering, and washing with water to obtain 2g of nickel mud and a zinc-chromium-containing solution. Adding a sulfuric acid solution into the solution, adjusting the pH value to 7, and filtering and washing to obtain 1.1g of zinc mud product and hexavalent chromium solution. And adding 10% sulfuric acid solution into the solution, adding 5% sodium bisulfite solution into the solution to reduce hexavalent chromium into trivalent chromium, and preparing 14g of chrome tanning agent.
TABLE 3
As can be seen from Table 3, about 24g of neutralized sludge was produced by alkaline leaching oxidation, the neutralized sludge was composed of zinc hydroxide containing a large amount of hexavalent chromium, and the yield of neutralized sludge was greatly reduced by first extracting zinc by alkaline leaching and then extracting chromium by oxidation. But the chromium content in the zinc solution obtained by direct alkaline leaching is still higher, so that the chromium content in the subsequent zinc product is higher. In contrast, using alkaline leaching reduction-oxidation, the yield of neutralized sludge can be reduced to 4.58% of alkaline leaching oxidation, and 98.61% of chromium in the zinc solution can be removed simultaneously, so that the chromium content in the zinc product is reduced from 0.08% to 0.0006%.
Comparing the three examples, it can be seen that the amount of neutralized sludge produced by the alkaline leaching reduction-oxidation process is about 1%, and the chromium content in the zinc solution-zinc sludge is less than 0.01%. Meanwhile, the higher the zinc content in the original chromium-containing sludge is, the higher the removal rate of the process on the neutralized sludge is, the lower the chromium content in the original sludge is, and the lower the chromium content in the zinc solution-zinc sludge is.
Claims (10)
1. A treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge is characterized by comprising the following steps:
(1) adding sulfuric acid into the chromium-containing sludge to completely dissolve the chromium-containing sludge;
(2) carrying out electrolytic copper removal on the solution obtained in the step (1), then removing iron in the solution by using an extraction method to obtain an impurity-removed solution and an iron extract, carrying out back extraction on the obtained iron extract to obtain a ferric ion solution, and treating with iron powder to obtain a ferrous sulfate solution;
(3) performing alkali washing on the impurity-removed solution obtained in the step (2), adjusting the pH value of the solution to 7-10, and filtering to obtain sludge 1 and a high-salt solution;
(4) adding alkali liquor into the high-salt solution obtained in the step (3), adjusting the pH value of the solution to 10-12, adding the ferrous sulfate solution obtained in the step (2), and filtering after the reaction is finished to obtain a ferrite product and an impurity-removed sulfate solution;
(5) further performing alkali washing on the sludge 1 obtained in the step (3), adjusting the pH value of the sludge to be more than 14, and putting the sludge into a reduction pool of a diaphragm electrolytic cell to obtain sludge 2 and a zinc-containing solution;
(6) putting the sludge 2 obtained in the step (5) into an oxidation tank of a diaphragm electrolytic cell, continuously dissolving the sludge with alkali liquor, filtering and washing the sludge after electrolytic oxidation to obtain a nickel sludge product and a zinc-containing hexavalent chromium solution;
(7) adding a sulfuric acid solution into the zinc-containing hexavalent chromium solution obtained in the step (6), adjusting the pH value of the solution to be 6-7, neutralizing, filtering and washing to obtain a zinc mud product and a hexavalent chromium solution;
(8) adding a strong acid and a reducing agent into the hexavalent chromium solution obtained in the step (7) to reduce the hexavalent chromium into trivalent chromium;
(9) and (4) adding strong base into the trivalent chromium solution obtained in the step (8), adjusting the alkalinity of the solution to be 32-34%, and drying the obtained solution to obtain a chromium tanning agent product.
2. The treatment method according to claim 1, wherein the mass concentration of the sulfuric acid in the step (1) is 10-40%, and the mass ratio of the acid addition amount to the sludge amount is 1: 1-4: 1.
3. the treatment method according to claim 1, wherein the extractant in the step (2) is one of P204 or N235, and the back extraction is carried out by using a sulfuric acid solution, and the concentration of the sulfuric acid solution is 5-20 wt%.
4. The treatment method according to claim 1, wherein the alkali used in the steps (3), (4) and (5) is at least one of a sodium hydroxide solution, a potassium hydroxide solution or ammonia water, and the concentration thereof is 5 to 20% by mass.
5. The process of claim 1, wherein the reaction conditions in step (4) are: the reaction temperature is 70-90 ℃, and the reaction time is 0.5-2 h.
6. The process of claim 1, wherein the cathode of the diaphragm electrolytic cell in steps (5) and (6) is a titanium plate, the anode is titanium iridium ruthenium coated, and the voltage between the plates is 24V.
7. The treatment method according to claim 1, wherein the solution temperature in the step (5) is required to be kept between 5 and 20 ℃, and the electrolysis time is 8 to 12 hours; and (4) keeping the temperature of the solution in the step (6) between 60 and 95 ℃, and electrolyzing for 8 to 12 hours.
8. The treatment method according to claim 1, wherein the strong acid in the step (8) is sulfuric acid with a mass concentration of 1-15%; the reducing agent is at least one of sodium bisulfite, sodium sulfite or potassium sulfite, and the mass concentration of the reducing agent is 1-5%.
9. The treatment method according to claim 1, wherein the strong base in the step (9) is at least one of a sodium hydroxide solution, a potassium hydroxide solution, a sodium carbonate solution or a sodium bicarbonate solution, and the mass concentration of the strong base is 30-40%.
10. The treatment method as claimed in claim 1, wherein the chromium-containing sludge comprises 3-20% of chromium, 2-15% of zinc ions, 1-5% of Cu, 1-5% of Fe and 1-5% of Ni, by mass.
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| CN202010223684.7A CN111304444B (en) | 2020-03-26 | 2020-03-26 | Treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112701372A (en) * | 2020-12-28 | 2021-04-23 | 湖南邦普循环科技有限公司 | Method for removing elemental copper from ternary battery waste and application thereof |
| CN113816847A (en) * | 2021-10-08 | 2021-12-21 | 上海良仁化工有限公司 | Method for preparing basic chromium acetate from chromium-containing sludge |
| CN113881849A (en) * | 2021-09-18 | 2022-01-04 | 荆门市格林美新材料有限公司 | Method for removing chromium from sulfate solution |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1827802A (en) * | 2006-03-24 | 2006-09-06 | 浙江工业大学 | Method for recovering valuable metals from electroplating sludge |
| CN101058436A (en) * | 2006-04-17 | 2007-10-24 | 上饶市华丰铜业有限公司 | Circuit board and electric plating sludge resource recovery process |
| CN101643243A (en) * | 2009-08-14 | 2010-02-10 | 扬州宁达贵金属有限公司 | Method for recycling copper, nickel, chromium, zinc and iron from plating sludge |
| CN103343229A (en) * | 2013-06-28 | 2013-10-09 | 江西理工大学 | Method for comprehensively recovering valuable metals from electroplating waste mud |
| CN104593598A (en) * | 2014-12-18 | 2015-05-06 | 北京矿冶研究总院 | Method for resource utilization of multiple metals in electroplating sludge |
| CN110713327A (en) * | 2019-10-16 | 2020-01-21 | 中建水务环保有限公司 | Method and device for continuously treating heavy metal polluted sludge |
-
2020
- 2020-03-26 CN CN202010223684.7A patent/CN111304444B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1827802A (en) * | 2006-03-24 | 2006-09-06 | 浙江工业大学 | Method for recovering valuable metals from electroplating sludge |
| CN101058436A (en) * | 2006-04-17 | 2007-10-24 | 上饶市华丰铜业有限公司 | Circuit board and electric plating sludge resource recovery process |
| CN101643243A (en) * | 2009-08-14 | 2010-02-10 | 扬州宁达贵金属有限公司 | Method for recycling copper, nickel, chromium, zinc and iron from plating sludge |
| CN103343229A (en) * | 2013-06-28 | 2013-10-09 | 江西理工大学 | Method for comprehensively recovering valuable metals from electroplating waste mud |
| CN104593598A (en) * | 2014-12-18 | 2015-05-06 | 北京矿冶研究总院 | Method for resource utilization of multiple metals in electroplating sludge |
| CN110713327A (en) * | 2019-10-16 | 2020-01-21 | 中建水务环保有限公司 | Method and device for continuously treating heavy metal polluted sludge |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112701372A (en) * | 2020-12-28 | 2021-04-23 | 湖南邦普循环科技有限公司 | Method for removing elemental copper from ternary battery waste and application thereof |
| CN112701372B (en) * | 2020-12-28 | 2022-03-15 | 湖南邦普循环科技有限公司 | Method for removing elemental copper from ternary battery waste and application thereof |
| CN113881849A (en) * | 2021-09-18 | 2022-01-04 | 荆门市格林美新材料有限公司 | Method for removing chromium from sulfate solution |
| CN113816847A (en) * | 2021-10-08 | 2021-12-21 | 上海良仁化工有限公司 | Method for preparing basic chromium acetate from chromium-containing sludge |
| CN113816847B (en) * | 2021-10-08 | 2023-09-19 | 上海良仁化工有限公司 | Method for preparing basic chromium acetate from chromium-containing sludge |
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