CN112143902B - Method for respectively recovering titanium, tungsten and vanadium from invalid SCR denitration catalyst - Google Patents
Method for respectively recovering titanium, tungsten and vanadium from invalid SCR denitration catalyst Download PDFInfo
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- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
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- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
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- C22B34/1236—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching
- C22B34/1254—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching using basic solutions or liquors
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Abstract
The invention discloses a method for respectively recovering titanium, tungsten and vanadium from a failed SCR denitration catalyst, which comprises the following steps: mixing the denitration catalyst with a dissolving agent for reaction to obtain a dissolving liquid and dissolving slag; leaching and dissolving the slag with a carbonic acid solution to obtain sodium-removed high titanium slag and a sodium bicarbonate solution; spraying a sodium bicarbonate solution into a gas furnace tail gas spray tower, collecting a sodium carbonate solution at the bottom of the spray tower, and condensing the spray tower tail gas to obtain a carbonic acid solution; mixing strontium oxide and the dissolution liquid for reaction to obtain causticized precipitation liquid and strontium salt mixed precipitation; mixing and reacting strontium salt mixed precipitate with a weak acid solution to obtain a vanadium enrichment solution and strontium tungstate slag, adding a sodium carbonate solution into the vanadium enrichment solution, and reacting to obtain a crude sodium vanadate solution and strontium carbonate slag; mixing strontium tungstate slag and a sodium carbonate solution for reaction to obtain a crude sodium tungstate solution and strontium carbonate slag; and drying and dehydrating the strontium carbonate slag, and calcining to obtain strontium oxide. The invention has high material recycling rate and high-efficiency recovery of titanium, tungsten and vanadium.
Description
Technical Field
The invention relates to the technical field of secondary resource utilization, in particular to a method for respectively recovering titanium, tungsten and vanadium from a failed SCR denitration catalyst.
Background
Nitrogen oxides (NOx) are one of the main pollutants of the atmospheric environment. Nitrogen oxides not only form acid rain, but also can cause chemical smog and harm human health. Coal-fired power generation plays an important role in energy structures in China. According to prediction, the proportion of coal-fired power generation in energy consumption is continuously reduced, but in 2050, the percentage of stone energy consumption such as coal, petroleum, natural gas and the like in China is still about 50%. The carbonaceous fuel inevitably produces nitrogen oxides during combustion. The national implementation of the emission standard of atmospheric pollutants of thermal power plants in 2012 (GB 13223-2011). By the end of 2014, more than 90% of thermal power plants in China are provided with vanadium-titanium SCR denitration devices. With the deepening of ecological civilization construction, industries such as cement plants, oil burning machines, gas-fired boilers, biomass boilers and the like which relate to high-temperature combustion adopt a denitration technology to realize clean production.
The most mature and widely applied catalyst in the SCR denitration catalyst is a vanadium-titanium catalyst. Due to V2O5The vanadium-titanium series waste SCR catalyst has biological toxicity, belongs to dangerous solid waste, and on the other hand, tungsten, vanadium and titanium belong to rare metal elements with higher values, and the resource utilization of the vanadium-titanium series waste SCR catalyst becomes a research hotspot recently.
The SCR denitration catalyst works at a high temperature for a long time, making its structure abnormally stable, resulting in tungsten oxide and vanadium oxide therein being difficult to be dissolved out. In order to obtain higher extraction efficiency of tungsten and vanadium, the addition amount of sodium hydroxide is far more than the theoretical amount in the alkali dissolution process, so that the dissolution liquid contains a large amount of excess sodium hydroxide. If the excess sodium hydroxide is neutralized by adding acid, the consumption cost of the reagent is increased.
Disclosure of Invention
The invention aims to provide a method for respectively recovering titanium, tungsten and vanadium from a failed SCR denitration catalyst, and aims to solve the problem that the existing vanadium-titanium system waste SCR denitration catalyst is difficult to efficiently recover.
In order to achieve the purpose, the method for respectively recovering titanium, tungsten and vanadium from the failed SCR denitration catalyst provided by the invention comprises the following steps:
(1) mixing the vanadium-titanium waste denitration catalyst and a stripping agent in proportion, carrying out a stripping reaction under the condition of normal-pressure boiling stirring, and after the reaction is finished, carrying out solid-liquid separation and water washing to obtain a stripping liquid and stripping slag, wherein the components of the vanadium-titanium waste denitration catalyst comprise oxygen, titanium, tungsten, vanadium and molybdenum, and the stripping agent is a sodium hydroxide solution and/or a causticized precipitation solution obtained in the step (4);
(2) placing the dissolved slag obtained in the step (1) into a leaching tank, leaching by using the carbonic acid solution obtained in the step (3), and eluting sodium ions in the dissolved slag to obtain sodium-removed high titanium slag and a sodium bicarbonate solution;
(3) spraying the sodium bicarbonate solution obtained in the step (2) into a tail gas spray tower of a gas furnace, decomposing and evaporating the sodium bicarbonate solution by using waste heat, collecting the sodium carbonate solution at the bottom of the spray tower, and condensing tail gas of the spray tower to obtain a carbonic acid solution;
(4) mixing strontium oxide and/or strontium oxide obtained in the step (7) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out causticization precipitation reaction at a certain temperature to enable tungstate, carbonate and vanadate in the solution to generate strontium salt precipitate, regenerating sodium hydroxide, and carrying out solid-liquid separation to obtain the mixed precipitate of the solution after causticization precipitation and strontium salt;
(5) mixing the strontium salt mixed precipitate obtained in the step (4) with a weak acid solution, selectively leaching vanadium, performing solid-liquid separation to obtain a vanadium enrichment solution and strontium tungstate slag, then adding the sodium carbonate solution obtained in the step (3) into the vanadium enrichment solution in proportion to perform strontium precipitation reaction, and performing solid-liquid separation to obtain a crude sodium vanadate solution and strontium carbonate slag;
(6) mixing the strontium tungstate residue obtained in the step (5) with the sodium carbonate solution obtained in the step (3) in proportion, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a crude sodium tungstate solution and strontium carbonate residue;
(7) and (4) drying and dehydrating the strontium carbonate slag obtained in the steps (5) and (6), and carrying out calcination decomposition operation at 1100-1250 ℃ to convert strontium carbonate into strontium oxide.
Preferably, the concentration of sodium hydroxide in the dissolution agent in the step (1) is 15wt.% to 32 wt.%.
Preferably, the solid-to-solid ratio of the digestion reaction solution in the step (1) is 3-7, the digestion temperature is 110-150 ℃, and the digestion time is 2-7 hours.
Preferably, the step (1) is carried out with a digestion reaction while collecting condensed water, which is used for water washing of the step (1).
Preferably, the amount of strontium oxide used in the causticization precipitation reaction in the step (4) is 0.8-0.95 times of the total molar amount of tungstate, carbonate and vanadate in the dissolution liquid, the reaction temperature is 80-100 ℃, and the reaction time is 0.5-1.0 hour.
Preferably, the weak acid solution in step (5) is a mixture of one or more of oxalic acid, citric acid, acetic acid, formic acid and tartaric acid.
Preferably, the amount of the sodium carbonate used in the carbonation reaction of the step (6) is 1.5-3.0 times of the molar weight of tungsten in the strontium tungstate slag, the reaction temperature is 130-170 ℃, and the reaction time is 0.5-1.0 hour.
The technical principle adopted by the invention is as follows:
according to the invention, under the condition of normal-pressure heating and boiling, tungsten and vanadium in the waste SCR catalyst are selectively dissolved out by using a sodium hydroxide solution, so that the tungsten and the vanadium are selectively separated from titanium to obtain dissolved slag and a dissolved liquid, and meanwhile, condensed water required by slag washing is obtained by evaporation. Then, soluble sodium ions carried in the dissolved slag can be further eluted by utilizing a carbonic acid solution leaching mode, and a small amount of sodium titanate in the dissolved slag can be converted into soluble sodium bicarbonate to be eluted, so that the sodium-removed high-titanium slag and a sodium bicarbonate solution are obtained. The sodium bicarbonate solution absorbs the waste heat in the tail gas spray tower of the gas boiler and is decomposed into sodium carbonate solution, water vapor and carbon dioxide, and the carbon dioxide in the tail gas is absorbed in the condensation process of the water vapor to obtain the carbonic acid solution required by leaching and removing sodium. Adding strontium oxide into the solution, precipitating tungsten and vanadium by utilizing the strong precipitation capability of strontium ions in alkaline solution on tungstate, carbonate and vanadate, and removing the carbonate in the solution to causticize the solution. The solution after causticizing precipitation treatment can be returned to the dissolution process. Further, decomposing and leaching strontium carbonate and strontium vanadate by using weak acid solution to obtain vanadium enrichment liquid and strontium tungstate slag. And then removing strontium from the vanadium enrichment solution by using sodium carbonate to obtain strontium carbonate and a crude sodium vanadate solution. And decomposing the strontium tungstate slag by using a sodium carbonate solution to obtain a crude sodium tungstate solution and strontium carbonate. And finally, decomposing the strontium carbonate by adopting a high-temperature calcination mode to obtain the strontium oxide which can be recycled.
The invention has the following beneficial effects:
the invention organically combines the wet treatment process and the fire treatment process, and the material recycling rate in the system is high, which is shown in the following steps: the water is recycled, the strontium carbonate is calcined and decomposed to realize the regeneration and recycling of strontium oxide, and the dissolution liquid is subjected to a causticization precipitation process to realize the regeneration and recycling of sodium hydroxide. After the vanadium-titanium series waste denitration catalyst is decomposed, the main valuable elements of titanium, tungsten and vanadium are respectively recovered, and the obtained products of high-titanium slag, sodium tungstate solution and sodium vanadate solution are high-quality raw materials of downstream titanium, tungsten and vanadium smelting enterprises. The extraction rate of titanium, tungsten and vanadium in the whole process can reach more than 99%, 97% and 90%.
Detailed Description
The invention provides a method for respectively recovering titanium, tungsten and vanadium from a failed SCR denitration catalyst, which comprises the following steps of:
(1) mixing the vanadium-titanium waste denitration catalyst and a stripping agent in proportion, carrying out a stripping reaction under the condition of normal-pressure boiling stirring, and after the reaction is finished, carrying out solid-liquid separation and water washing to obtain a stripping liquid and stripping slag, wherein the components of the vanadium-titanium waste denitration catalyst comprise oxygen, titanium, tungsten, vanadium and molybdenum, and the stripping agent is a sodium hydroxide solution and/or a causticized precipitation solution obtained in the step (4);
(2) placing the dissolved slag obtained in the step (1) into a leaching tank, leaching by using the carbonic acid solution obtained in the step (3), and eluting sodium ions in the dissolved slag to obtain sodium-removed high titanium slag and a sodium bicarbonate solution;
(3) spraying the sodium bicarbonate solution obtained in the step (2) into a tail gas spray tower of a gas furnace, decomposing and evaporating the sodium bicarbonate solution by using waste heat, collecting the sodium carbonate solution at the bottom of the spray tower, and condensing tail gas of the spray tower to obtain a carbonic acid solution;
(4) mixing strontium oxide and/or strontium oxide obtained in the step (7) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out causticization precipitation reaction at a certain temperature to enable tungstate, carbonate and vanadate in the solution to generate strontium salt precipitate, regenerating sodium hydroxide, and carrying out solid-liquid separation to obtain the mixed precipitate of the solution after causticization precipitation and strontium salt;
(5) mixing the strontium salt mixed precipitate obtained in the step (4) with a weak acid solution, selectively leaching vanadium, performing solid-liquid separation to obtain a vanadium enrichment solution and strontium tungstate slag, then adding the sodium carbonate solution obtained in the step (3) into the vanadium enrichment solution in proportion to perform strontium precipitation reaction, and performing solid-liquid separation to obtain a crude sodium vanadate solution and strontium carbonate slag;
(6) mixing the strontium tungstate residue obtained in the step (5) with the sodium carbonate solution obtained in the step (3) in proportion, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a crude sodium tungstate solution and strontium carbonate residue;
(7) and (4) drying and dehydrating the strontium carbonate slag obtained in the steps (5) and (6), and carrying out calcination decomposition operation at 1100-1250 ℃ to convert strontium carbonate into strontium oxide.
The present invention will be further illustrated by the following examples, but is not limited thereto.
Example 1
The waste SCR denitration catalysts with the titanium, tungsten and vanadium contents of 42.55 wt.%, 3.85 wt.% and 0.45 wt.% were ground into powders, and 5 parts of 200g of the powders were subjected to comparative tests of dissolution conditions. In the test, the heat of the reaction system is maintained in an oil bath mode, after the dissolution reaction is finished, the reaction system is filtered, the slag is washed by hot water, and the wet slag is dried at 100 ℃ to analyze the content of tungsten and vanadium in the dissolution slag. The test conditions and results are shown in the following table.
Example 2
3.5kg of waste SCR denitration catalyst powder with the titanium, tungsten and vanadium contents of 42.55 wt.%, 3.85 wt.% and 0.45 wt.% are mixed with 15wt.% of sodium hydroxide solution, the liquid-solid ratio is 7, the oil bath temperature is 130 ℃, stirring and dissolving are carried out for 7 hours, and the contents of sodium, tungsten and vanadium in dissolved slag obtained after filtering, washing and drying are respectively 4.7 wt.%, 0.18 wt.% and 0.19 wt.%.
Transferring the dissolved slag into a leaching tank, leaching for 7 hours by using carbonic acid solution, and then removing sodium in the high titanium slag with sodium content of 0.39 wt.% (dry basis).
And equally dividing the dissolved solution into 4 parts, adding strontium oxide according to different conditions to carry out causticization precipitation reaction, and analyzing the concentration of tungsten, molybdenum and vanadium in the solution after the reaction is finished to obtain the precipitation rate. The test conditions and results are shown in the following table.
Example 3
4.5kg of waste SCR denitration catalyst powder with titanium, tungsten, molybdenum and vanadium contents of 43.75 wt.%, 3.63 wt.%, 0.60 wt.% and 0.41 wt.% are mixed with causticized precipitation solution with sodium hydroxide content of 23 wt.%, the liquid-solid ratio is 4, the oil bath temperature is 125 ℃, stirring is carried out for dissolving for 4.5 hours, and the sodium, tungsten, molybdenum and vanadium contents in dissolved slag obtained after filtering, water washing and drying are respectively 4.1 wt.%, 0.17 wt.%, 0.12 wt.% and 0.18 wt.%.
Transferring the dissolved slag into a leaching tank, and leaching with a carbonic acid solution; and spraying the sodium bicarbonate solution obtained by leaching into a tail gas spray tower of the gas furnace, decomposing and evaporating the sodium bicarbonate solution by utilizing waste heat, enriching sodium ions at the bottom of the spray tower to obtain a sodium carbonate solution, and condensing tail gas of the spray tower to obtain a carbonic acid solution which returns to the leaching tank. After leaching for 8 hours, the sodium content in the sodium-removed high titanium slag is 0.31 wt.% (dry basis).
Heating the dissolution liquid to 95 ℃, slowly adding strontium oxide under the stirring state, wherein the adding amount of the strontium oxide is 0.95 times of the total molar amount of tungstate, carbonate and vanadate in the dissolution liquid, stirring for reacting for 45 minutes, and performing solid-liquid separation to obtain a strontium salt mixed precipitate and a causticized precipitate liquid. The analysis result shows that the vanadium precipitation rate is 72.7 percent, and the tungsten precipitation rate is 92.6 percent.
The strontium salt mixed precipitate is equally divided into 5 parts, the 5 parts are respectively mixed with weak acid solution, the room temperature reaction is carried out for 3 hours, the leaching rate of vanadium is calculated according to the change of the vanadium content in the solution, and the test conditions and the results are shown in the following table.
| Numbering | Kind of weak acid solution | Concentration of weak acid solution | Vanadium leaching rate |
| 3-1 | Oxalic acid | 0.5mol/L | 97％ |
| 3-2 | Citric acid | 0.33mol/L | 98％ |
| 3-3 | Acetic acid | 1mol/L | 93％ |
| 3-4 | Formic acid | 1mol/L | 90％ |
| 3-5 | Tartaric acid | 0.5mol/L | 96％ |
Gas formation was observed during the experiment, which was caused by decomposition of strontium carbonate. As can be seen from the above table, most of the vanadium is leached under weak acid condition to obtain strontium salt precipitate mainly containing strontium tungstate. Uniformly mixing the strontium tungstate slag, equally dividing into 4 parts, adding a sodium carbonate solution according to different conditions to perform carbonation reaction, and performing solid-liquid separation to obtain a crude sodium tungstate solution and strontium carbonate slag respectively. The leaching rate of tungsten is calculated by measuring the content of tungsten in the strontium carbonate slag, and the test conditions and results are shown in the table below.
Example 4
3.5kg of waste SCR denitration catalyst powder with titanium, tungsten, molybdenum and vanadium contents of 43.75 wt.%, 3.63 wt.%, 0.60 wt.% and 0.41 wt.% are mixed with a sodium hydroxide solution with the concentration of 26 wt.%, the liquid-solid ratio is 5, the oil bath temperature is 115 ℃, stirring and dissolving are carried out for 7 hours, and the contents of sodium, tungsten, molybdenum and vanadium in dissolved slag obtained after filtering, water washing and drying are respectively 3.1 wt.%, 0.17 wt.%, 0.10 wt.% and 0.12 wt.%.
Transferring the dissolved slag into a leaching tank, leaching for 10 hours by using carbonic acid solution, and then removing sodium in the high titanium slag with sodium content of 0.26 wt.% (dry basis).
Heating the dissolution liquid to 90 ℃, slowly adding strontium oxide under the stirring state, wherein the adding amount of the strontium oxide is 0.9 times of the total molar amount of tungstate, carbonate and vanadate in the dissolution liquid, stirring for reacting for 60 minutes, and carrying out solid-liquid separation to obtain a strontium salt mixed precipitate and a causticized precipitate liquid. The analysis result shows that the vanadium precipitation rate is 71.3 percent and the tungsten precipitation rate is 91.9 percent.
Mixing the strontium salt mixed precipitate with 1mol/L acetic acid solution, reacting at room temperature for 2 hours, selectively leaching vanadium in the strontium salt mixed precipitate, and decomposing strontium carbonate to generate bubbles in the process. And carrying out solid-liquid separation to obtain strontium tungstate slag and vanadium enrichment liquid. The leaching rate of vanadium was 91% calculated by the change in vanadium content in the solution. Further, sodium carbonate is added into the vanadium enrichment liquid, the end point pH value is 11.3, and a crude sodium vanadate solution and strontium carbonate slag are obtained after solid-liquid separation. And drying the strontium carbonate slag, adding 5wt.% of carbon powder, calcining for 1.5 hours at 1100 ℃, and performing a hot water washing experiment on the calcined slag, wherein the water solubility is 96 wt.%, which indicates that most of strontium in the strontium carbonate slag is converted into strontium oxide which can be dissolved by hot water.
On the other hand, mixing a sodium carbonate solution with the strontium tungstate slag for carbonation reaction, wherein the using amount of sodium carbonate is 3.0 times of the molar amount of tungsten in the strontium tungstate slag, the reaction temperature is 150 ℃, the reaction time is 1 hour, and the crude sodium tungstate solution and the strontium tungstate slag are obtained after solid-liquid separation. The leaching rate of tungsten is 99.2 percent by measuring the content of tungsten in the strontium carbonate slag. Drying and dehydrating the strontium carbonate slag, equally dividing into 3 parts, respectively calcining and decomposing at different temperatures, and characterizing the decomposition rate of the strontium carbonate slag through a hot water washing experiment. The test conditions and results are shown in the following table.
| Numbering | Calcination temperature | Calcination time | Water solubility |
| 4-1 | 1150℃ | 1.5 hours | 96wt.％ |
| 4-2 | 1200℃ | 1.0 hour | 98wt.％ |
| 4-3 | 1250℃ | 0.5 hour | 97wt.％ |
As can be seen from the above table, the strontium carbonate slag is decomposed by calcination, and most of strontium is converted into strontium oxide which can be dissolved by hot water.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention.
Claims (7)
1. A method for respectively recovering titanium, tungsten and vanadium from a failed SCR denitration catalyst is characterized by comprising the following steps of:
(1) mixing the vanadium-titanium waste denitration catalyst and a stripping agent in proportion, carrying out a stripping reaction under the condition of normal-pressure boiling stirring, and after the reaction is finished, carrying out solid-liquid separation and water washing to obtain a stripping liquid and stripping slag, wherein the components of the vanadium-titanium waste denitration catalyst comprise oxygen, titanium, tungsten, vanadium and molybdenum, and the stripping agent is a sodium hydroxide solution and/or a causticized precipitation solution obtained in the step (4);
(2) placing the dissolved slag obtained in the step (1) into a leaching tank, leaching by using a carbonic acid solution, and eluting sodium ions in the dissolved slag to obtain sodium-removed high-titanium slag and a sodium bicarbonate solution;
(3) spraying the sodium bicarbonate solution obtained in the step (2) into a tail gas spray tower of a gas furnace, decomposing and evaporating the sodium bicarbonate solution by utilizing waste heat, collecting the sodium carbonate solution at the bottom of the spray tower, and condensing tail gas of the spray tower to obtain a carbonic acid solution, wherein the carbonic acid solution obtained in the step (3) is returned to the step (2) for leaching;
(4) mixing strontium oxide and/or strontium oxide obtained in the step (7) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out causticization precipitation reaction at a certain temperature to enable tungstate, carbonate and vanadate in the solution to generate strontium salt precipitate, regenerating sodium hydroxide, and carrying out solid-liquid separation to obtain the mixed precipitate of the solution after causticization precipitation and strontium salt;
(5) mixing the strontium salt mixed precipitate obtained in the step (4) with a weak acid solution, selectively leaching vanadium, performing solid-liquid separation to obtain a vanadium enrichment solution and strontium tungstate slag, then adding the sodium carbonate solution obtained in the step (3) into the vanadium enrichment solution in proportion to perform strontium precipitation reaction, and performing solid-liquid separation to obtain a crude sodium vanadate solution and strontium carbonate slag;
(6) mixing the strontium tungstate residue obtained in the step (5) with the sodium carbonate solution obtained in the step (3) in proportion, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a crude sodium tungstate solution and strontium carbonate residue;
(7) and (4) drying and dehydrating the strontium carbonate slag obtained in the steps (5) and (6), and carrying out calcination decomposition operation at 1100-1250 ℃ to convert strontium carbonate into strontium oxide.
2. The method for separately recovering titanium, tungsten and vanadium from a spent SCR denitration catalyst according to claim 1, wherein the concentration of sodium hydroxide in the leaching agent in the step (1) is 15wt.% to 32 wt.%.
3. The method for respectively recovering titanium, tungsten and vanadium from the spent SCR denitration catalyst according to claim 1, wherein the solid-to-solid ratio of the leaching reaction solution in the step (1) is 3-7, the leaching temperature is 110-150 ℃, and the leaching time is 2-7 hours.
4. The method for separately recovering titanium, tungsten and vanadium from a spent SCR denitration catalyst according to claim 1, wherein the step (1) is performed with a digestion reaction while collecting condensed water, and the condensed water is used for water washing of the step (1).
5. The method for respectively recovering titanium, tungsten and vanadium from the spent SCR denitration catalyst according to claim 1, wherein the amount of strontium oxide used in the causticizing precipitation reaction in the step (4) is 0.8-0.95 times of the total molar amount of tungstate, carbonate and vanadate in the dissolution liquid, the reaction temperature is 80-100 ℃, and the reaction time is 0.5-1.0 hour.
6. The method for separately recovering titanium, tungsten and vanadium from a spent SCR denitration catalyst according to claim 1, wherein the weak acid solution in the step (5) is a mixture of one or more of oxalic acid, citric acid, acetic acid, formic acid and tartaric acid.
7. The method for respectively recovering titanium, tungsten and vanadium from the failed SCR denitration catalyst as claimed in claim 1, wherein the sodium carbonate used in the carbonation reaction in the step (6) is 1.5 to 3.0 times of the molar weight of tungsten in the strontium tungstate slag, the reaction temperature is 130 to 170 ℃, and the reaction time is 0.5 to 1.0 hour.
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| CN104263946A (en) * | 2014-10-10 | 2015-01-07 | 武汉凯迪电力环保有限公司 | Method for recovering tungsten, vanadium and titanium from waste SCR (selective catalytic reduction) denitration catalyst |
| JP2015189996A (en) * | 2014-03-27 | 2015-11-02 | Jx日鉱日石金属株式会社 | High-purity strontium and production method thereof |
| JP2017048437A (en) * | 2015-09-03 | 2017-03-09 | 株式会社東芝 | Rare metal recovery method |
| CN107185554A (en) * | 2017-07-14 | 2017-09-22 | 北京宏承宝然科技有限公司 | A kind of method that useless SCR denitration cleaning is recycled |
| CN110468278A (en) * | 2019-09-09 | 2019-11-19 | 中南大学 | A method of handling useless denitrating catalyst |
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| JP2015189996A (en) * | 2014-03-27 | 2015-11-02 | Jx日鉱日石金属株式会社 | High-purity strontium and production method thereof |
| CN104263946A (en) * | 2014-10-10 | 2015-01-07 | 武汉凯迪电力环保有限公司 | Method for recovering tungsten, vanadium and titanium from waste SCR (selective catalytic reduction) denitration catalyst |
| JP2017048437A (en) * | 2015-09-03 | 2017-03-09 | 株式会社東芝 | Rare metal recovery method |
| CN107185554A (en) * | 2017-07-14 | 2017-09-22 | 北京宏承宝然科技有限公司 | A kind of method that useless SCR denitration cleaning is recycled |
| CN110468278A (en) * | 2019-09-09 | 2019-11-19 | 中南大学 | A method of handling useless denitrating catalyst |
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