CN113881849A - Method for removing chromium from sulfate solution - Google Patents
Method for removing chromium from sulfate solution Download PDFInfo
- Publication number
- CN113881849A CN113881849A CN202111110282.7A CN202111110282A CN113881849A CN 113881849 A CN113881849 A CN 113881849A CN 202111110282 A CN202111110282 A CN 202111110282A CN 113881849 A CN113881849 A CN 113881849A
- Authority
- CN
- China
- Prior art keywords
- chromium
- solution
- reaction
- sulfate solution
- stage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title claims abstract description 58
- 229910052804 chromium Inorganic materials 0.000 title claims abstract description 57
- 239000011651 chromium Substances 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 title claims abstract description 35
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 title claims abstract description 30
- 239000000243 solution Substances 0.000 claims abstract description 59
- 238000006243 chemical reaction Methods 0.000 claims abstract description 35
- 239000012535 impurity Substances 0.000 claims abstract description 21
- 239000000706 filtrate Substances 0.000 claims abstract description 19
- 239000002253 acid Substances 0.000 claims abstract description 10
- 239000012670 alkaline solution Substances 0.000 claims abstract description 10
- 230000035484 reaction time Effects 0.000 claims abstract description 8
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical group O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910000423 chromium oxide Inorganic materials 0.000 claims abstract description 7
- 238000001914 filtration Methods 0.000 claims abstract description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 9
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 6
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 6
- 239000000839 emulsion Substances 0.000 claims description 6
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 3
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 3
- 239000000920 calcium hydroxide Substances 0.000 claims description 3
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 3
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 3
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 7
- 229910001385 heavy metal Inorganic materials 0.000 description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000003513 alkali Substances 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 238000002386 leaching Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 239000010802 sludge Substances 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- 235000010269 sulphur dioxide Nutrition 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910001430 chromium ion Inorganic materials 0.000 description 1
- GRWVQDDAKZFPFI-UHFFFAOYSA-H chromium(III) sulfate Chemical compound [Cr+3].[Cr+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O GRWVQDDAKZFPFI-UHFFFAOYSA-H 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000001556 precipitation 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
- 235000010265 sodium sulphite Nutrition 0.000 description 1
Classifications
-
- 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
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G37/00—Compounds of chromium
- C01G37/02—Oxides or hydrates thereof
- C01G37/033—Chromium trioxide; Chromic acid
-
- 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Inorganic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The invention discloses a method for removing chromium from sulfate solution, which comprises the following steps: (1) adding a chromium-containing sulfate solution into an acid solution, and introducing the solution into a pressure reaction kettle for filter pressing reaction to obtain a first-stage filtrate and a first-stage filter residue; the reaction process conditions are as follows: the reaction pH is 1.5-3.0, the reaction temperature is 150-160 ℃, the reaction pressure is 0.6-0.65 MPa, and the reaction time is 2-3 h; (2) adjusting the pH of the first-stage filtrate by using an alkaline solution, removing impurities, and filtering to obtain a second-stage filtrate and a second-stage filter residue, wherein the second-stage filtrate is a sulfate solution with chromium removed, and the second-stage filter residue is chromium oxide; the impurity removal process conditions are as follows: the pH value of the impurity removal is 3.0-4.5, the impurity removal temperature is 70-80 ℃, and the impurity removal reaction time is 2-3 h. The method has good effect of removing chromium in the solution and has the same effect of removing chromium under the condition of high chromium concentration.
Description
Technical Field
The invention belongs to the technical field of heavy metal recovery, and particularly relates to a method for removing chromium from a sulfate solution.
Background
The problems of low heavy metal content and high chromium content generally exist when heavy metals are recovered from nickel-containing sludge or hard alloy waste, the leaching rate of chromium is very high when the chromium is leached and dissolved, the chromium cannot be effectively separated from the heavy metals, the treatment difficulty is high, and the recovery rate of the heavy metals is lower as the chromium content is higher. Chromium in the nickel-containing sludge or the hard alloy waste mainly exists in a trivalent chromium salt form, the chromium is removed by a hydrolysis precipitation method in the traditional chromium removal process, the method is suitable for removing the chromium with very low content, the condition of high chromium content cannot be met, and the influence on the recovery rate of heavy metals is large.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a method for removing chromium from a sulfate solution, which has good effect of removing chromium in the solution and the same effect of removing chromium with high concentration.
The invention adopts the following technical scheme:
a method for removing chromium from a sulfate solution, the method comprising the steps of:
(1) adding an acid solution into the chromium-containing sulfate solution, introducing the solution into a pressure reaction kettle for reaction, and filtering after the reaction is finished to obtain a first-stage filtrate and a first-stage filter residue; the process conditions of the reaction in the pressure reaction kettle are as follows: the reaction pH is 1.5-3.0, the reaction temperature is 150-160 ℃, the reaction pressure is 0.6-0.65 MPa, and the reaction time is 2-3 h;
(2) adjusting the pH of the first-stage filtrate by using an alkaline solution, removing impurities, and filtering to obtain a second-stage filtrate and a second-stage filter residue, wherein the second-stage filtrate is a sulfate solution with chromium removed, and the second-stage filter residue is chromium oxide; the impurity removal process conditions are as follows: the pH value of the impurity removal is 3.0-4.5, the impurity removal temperature is 70-80 ℃, and the impurity removal reaction time is 2-3 h.
The method for removing chromium from a sulfate solution according to the above, characterized in that the acid solution in step (1) is sulfuric acid.
The method for removing chromium from the sulfate solution is characterized in that in the step (1), the acid solution is added into the chromium-containing sulfate solution, the initial pH is controlled to be 2.0-3.0, and the solution is introduced into a pressure reaction kettle for reaction after being stabilized.
The method for removing chromium from the sulfate solution is characterized in that the first-stage filtrate in the step (1) is the low-chromium sulfate solution, wherein chromium is less than or equal to 150mg/L, the first-stage filter residue is chromium oxide, and the chromium removal rate is more than or equal to 95%.
The method for removing chromium from the sulfate solution is characterized in that the alkaline solution in the step (2) is one or more of sodium hydroxide solution, sodium carbonate solution, sodium bicarbonate solution, calcium carbonate emulsion and calcium hydroxide emulsion.
The method for removing chromium from a sulfate solution according to the above, characterized in that the concentration of the alkaline solution in the step (2) is 5% to 15%.
The invention has the beneficial technical effects that: in the material treatment process, high-pressure chromium removal is firstly carried out to effectively remove high-concentration chromium without loss of valuable metals, and the second step of fine chromium removal is carried out, so that the recovery rate of the valuable metals is ensured, and the good removal effect is ensured; no obvious harmful gas such as hydrogen sulfide, sulfur dioxide and the like is discharged in the second-stage leaching treatment process, and the treatment process is safe, environment-friendly and harmless. The method adopts a two-stage treatment mode for removing chromium in the solution, namely, one-stage rough removal and two-stage fine removal, so that the chromium ions can achieve good removal effect under any concentration, and the application range is wide.
Detailed Description
The method for removing chromium from sulfate solution comprises the following steps:
(1) adding an acid solution into a sulfate solution containing chromium, and introducing the sulfate solution into a reaction kettle for filter pressing reaction to obtain a first-stage filtrate and a first-stage filter residue; the process conditions of the filter pressing reaction are as follows: the reaction pH is 1.5-3.0, the reaction temperature is 150-160 ℃, the reaction pressure is 0.6-0.65 MPa, and the reaction time is 2-3 h; if the reaction pressure is less than 0.6MPa-0.65MPa, the pressure can be increased by compressed air, and the reaction pressure and temperature are ensured. The acid solution is sulfuric acid. Adding the acid solution into the chromium-containing sulfate solution, controlling the initial pH to be 2.0-3.0, and introducing the solution into a pressure reaction kettle for reaction after the solution is stable. The first stage filtrate is low chromium sulfate solution with chromium less than or equal to 150mg/L, and the first stage filter residue is chromium oxide with chromium removal rate greater than or equal to 95%. .
(2) Adjusting the pH of the first-stage filtrate by using an alkaline solution, removing impurities, and filtering to obtain a second-stage filtrate and a second-stage filter residue, wherein the second-stage filtrate is a sulfate solution with chromium removed, and the second-stage filter residue is chromium oxide; the impurity removal process conditions are as follows: the pH value of the impurity removal is 3.0-4.5, the impurity removal temperature is 70-80 ℃, and the impurity removal reaction time is 2-3 h. The alkaline solution is one or more of sodium hydroxide solution, sodium carbonate solution, sodium bicarbonate solution, calcium carbonate emulsion and calcium hydroxide emulsion, and the concentration of the alkaline solution is 5-15%. And dilute alkali is used during second-stage impurity removal, so that valuable metal loss caused by local alkali passing is prevented. Before removing chromium in the solution, the chromium is ensured to exist in a trivalent form, and if the chromium is hexavalent, one of sodium sulfite, sodium pyrosulfite and sulfur dioxide is required to be used for reduction.
Claims (6)
1. A method for removing chromium from a sulfate solution, the method comprising the steps of:
(1) adding an acid solution into the chromium-containing sulfate solution, introducing the solution into a pressure reaction kettle for reaction, and filtering after the reaction is finished to obtain a first-stage filtrate and a first-stage filter residue; the process conditions of the reaction in the pressure reaction kettle are as follows: the reaction pH is 1.5-3.0, the reaction temperature is 150-160 ℃, the reaction pressure is 0.6-0.65 MPa, and the reaction time is 2-3 h;
(2) adjusting the pH of the first-stage filtrate by using an alkaline solution, removing impurities, and filtering to obtain a second-stage filtrate and a second-stage filter residue, wherein the second-stage filtrate is a sulfate solution with chromium removed, and the second-stage filter residue is chromium oxide; the impurity removal process conditions are as follows: the pH value of the impurity removal is 3.0-4.5, the impurity removal temperature is 70-80 ℃, and the impurity removal reaction time is 2-3 h.
2. The method for removing chromium from a sulfate solution according to claim 1, wherein the acid solution in step (1) is sulfuric acid.
3. The method for removing chromium from a sulfate solution according to claim 1, wherein the acid solution is added to the chromium-containing sulfate solution in the step (1) to control the initial pH to 2.0 to 3.0, and the solution is introduced into the pressure reactor for reaction after being stabilized.
4. The method for removing chromium from a sulfate solution according to claim 1, wherein the first stage filtrate in step (1) is a low-chromium sulfate solution, wherein chromium is less than or equal to 150mg/L, the first stage filter residue is chromium oxide, and the chromium removal rate is greater than or equal to 95%.
5. The method for removing chromium from a sulfate solution according to claim 1, wherein the alkaline solution in step (2) is one or more of a sodium hydroxide solution, a sodium carbonate solution, a sodium bicarbonate solution, a calcium carbonate emulsion and a calcium hydroxide emulsion.
6. The process for removing chromium from a sulfate solution as set forth in claim 1, wherein the concentration of the alkaline solution in step (2) is 5-15%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111110282.7A CN113881849A (en) | 2021-09-18 | 2021-09-18 | Method for removing chromium from sulfate solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111110282.7A CN113881849A (en) | 2021-09-18 | 2021-09-18 | Method for removing chromium from sulfate solution |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113881849A true CN113881849A (en) | 2022-01-04 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111110282.7A Pending CN113881849A (en) | 2021-09-18 | 2021-09-18 | Method for removing chromium from sulfate solution |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113881849A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4260491A (en) * | 1978-11-15 | 1981-04-07 | Amchem Products, Inc. | Chrome removal waste treatment process |
| JPH05105451A (en) * | 1991-10-18 | 1993-04-27 | Kazumasa Otsuka | Production of high purity chromium (vi) oxide solution from composition containing trivalent chromium and/or hexavalent chromium |
| US5211853A (en) * | 1992-07-31 | 1993-05-18 | Huron Tech Corp. | Method for the removal of chromium compounds from aqueous solutions |
| WO2008092363A1 (en) * | 2007-01-26 | 2008-08-07 | Hunan Joyfly Technology Development Co., Ltd | A method of preparing chromic oxide and ferrous oxalate from carbon ferrochrome |
| CN103602819A (en) * | 2013-11-29 | 2014-02-26 | 中南大学 | Comprehensive recovery method of vanadate-chromate-containing solution |
| CN109735714A (en) * | 2019-01-30 | 2019-05-10 | 鲍君杰 | A kind of processing method of stainless steel oxidation skin |
| CN111304444A (en) * | 2020-03-26 | 2020-06-19 | 无锡中天固废处置有限公司 | Treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge |
-
2021
- 2021-09-18 CN CN202111110282.7A patent/CN113881849A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4260491A (en) * | 1978-11-15 | 1981-04-07 | Amchem Products, Inc. | Chrome removal waste treatment process |
| JPH05105451A (en) * | 1991-10-18 | 1993-04-27 | Kazumasa Otsuka | Production of high purity chromium (vi) oxide solution from composition containing trivalent chromium and/or hexavalent chromium |
| US5211853A (en) * | 1992-07-31 | 1993-05-18 | Huron Tech Corp. | Method for the removal of chromium compounds from aqueous solutions |
| WO2008092363A1 (en) * | 2007-01-26 | 2008-08-07 | Hunan Joyfly Technology Development Co., Ltd | A method of preparing chromic oxide and ferrous oxalate from carbon ferrochrome |
| CN103602819A (en) * | 2013-11-29 | 2014-02-26 | 中南大学 | Comprehensive recovery method of vanadate-chromate-containing solution |
| CN109735714A (en) * | 2019-01-30 | 2019-05-10 | 鲍君杰 | A kind of processing method of stainless steel oxidation skin |
| CN111304444A (en) * | 2020-03-26 | 2020-06-19 | 无锡中天固废处置有限公司 | Treatment method for separating and recovering copper, iron, zinc, nickel and chromium from chromium-containing sludge |
Non-Patent Citations (1)
| Title |
|---|
| 天津化工研究院组织翻译: "《无机盐工艺学，上册》", 30 September 1982, 化学工业出版社 * |
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| PB01 | Publication | ||
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| RJ01 | Rejection of invention patent application after publication | ||
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Application publication date: 20220104 |