CN112143903B - Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst - Google Patents
Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst Download PDFInfo
- Publication number
- CN112143903B CN112143903B CN202011167044.5A CN202011167044A CN112143903B CN 112143903 B CN112143903 B CN 112143903B CN 202011167044 A CN202011167044 A CN 202011167044A CN 112143903 B CN112143903 B CN 112143903B
- Authority
- CN
- China
- Prior art keywords
- solution
- vanadium
- tungsten
- strontium
- slag
- 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.)
- Active
Links
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
-
- 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
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/12—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions
-
- 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
- C22B34/10—Obtaining titanium, zirconium or hafnium
- C22B34/12—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
- 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
-
- 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
- C22B34/20—Obtaining niobium, tantalum or vanadium
- C22B34/22—Obtaining vanadium
- C22B34/225—Obtaining vanadium from spent catalysts
-
- 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
- C22B34/36—Obtaining tungsten
- C22B34/365—Obtaining tungsten from spent catalysts
-
- 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 discloses a method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalysts, which comprises the following steps: reacting the denitration catalyst with a dissolving agent to obtain a dissolving liquid and dissolving slag; leaching the dissolved slag by using a carbonic acid solution to obtain sodium-removed high titanium slag and a sodium bicarbonate solution; spraying a sodium bicarbonate solution into a tail gas spray tower of the gas furnace, collecting the sodium carbonate solution at the bottom of the spray tower, and condensing the tail gas to obtain a carbonic acid solution; mixing strontium chloride and the dissolution liquid for reaction to obtain vanadium-precipitated liquid and strontium vanadate slag; mixing strontium chloride and the solution after vanadium precipitation to react to obtain solution after tungsten precipitation and strontium tungstate slag; mixing strontium vanadate slag and a sodium carbonate solution for reaction to obtain a sodium vanadate solution and strontium carbonate slag; mixing strontium tungstate residue with a hydrochloric acid solution for reaction to obtain a solution after decomposition of tungstic acid and acid; adding the strontium carbonate slag and/or the sodium carbonate solution into the acid decomposed solution to obtain a neutral strontium chloride solution. The invention is a wet process, the material recycling rate in the system is high, and titanium, tungsten and vanadium are respectively recovered.
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 waste SCR denitration catalysts.
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 waste SCR denitration catalysts, and aims to solve the problem that the existing SCR denitration catalysts are difficult to fully recover.
In order to achieve the purpose, the method for respectively recovering titanium, tungsten and vanadium from the waste SCR denitration catalyst provided by the invention comprises the following steps:
(1) mixing a waste SCR 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 waste SCR denitration catalyst is a vanadium-titanium denitration catalyst and comprises oxygen, titanium, tungsten, vanadium and molybdenum; the dissolving agent is one or more of a sodium hydroxide solution, a tungsten precipitation solution obtained in the step (5), a desalted solution obtained in the step (6);
(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 chloride or the neutral strontium chloride solution obtained in the step (9) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out vanadium precipitation reaction at a certain temperature, and carrying out solid-liquid separation to obtain vanadium precipitation liquid and strontium vanadate slag;
(5) mixing strontium chloride or the neutral strontium chloride solution obtained in the step (9) with the vanadium-precipitated solution obtained in the step (4) according to a certain proportion, performing tungsten precipitation reaction at a certain temperature, and performing solid-liquid separation to obtain tungsten-precipitated solution and strontium tungstate slag;
(6) when the concentration of sodium chloride in the tungsten-precipitated liquid obtained in the step (5) is more than 150g/L, carrying out evaporation crystallization operation on the tungsten-precipitated liquid, collecting condensed water, and obtaining desalted liquid and sodium chloride crystals;
(7) mixing the strontium vanadate slag obtained in the step (4) with a sodium carbonate solution, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a sodium vanadate solution and strontium carbonate slag;
(8) mixing the strontium tungstate residue obtained in the step (5) with a hydrochloric acid solution, carrying out acid decomposition reaction at a certain temperature, and carrying out solid-liquid separation to obtain tungstic acid and a solution after acid decomposition;
(9) and (4) adding the strontium carbonate slag obtained in the step (7) and/or the sodium carbonate solution obtained in the step (3) into the acid decomposed liquid obtained in the step (8), and performing neutralization reaction to obtain a neutral strontium chloride solution.
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 dosage of strontium chloride in the vanadium precipitation reaction in the step (4) is 1.5-3 times of the molar weight of vanadium in the dissolution liquid, the reaction temperature is 80-100 ℃, and the reaction time is 0.5-1.0 hour.
Preferably, the amount of strontium chloride in the tungsten precipitation reaction in the step (5) is 0.8-1.2 times of the molar amount of tungsten in the solution after vanadium precipitation, the reaction temperature is 80-100 ℃, and the reaction time is 0.5-1.0 hour.
Preferably, the amount of the sodium carbonate used in the carbonation reaction of the step (7) is 1.5-3.0 times of the molar amount of strontium in the strontium vanadate slag, the reaction temperature is 110-140 ℃, and the reaction time is 0.5-1.0 hour.
Preferably, the amount of hydrochloric acid used in the acid decomposition reaction in the step (8) is 10-16 times of the molar weight of strontium in the strontium tungstate slag, the reaction temperature is above 70 ℃, and the reaction time is 0.5-1.5 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).
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 chloride into the dissolution liquid, and precipitating tungsten and vanadium in the dissolution liquid by a step-by-step precipitation method by utilizing the difference of the precipitation capacity of strontium ions on tungsten and vanadium in an alkaline solution to respectively obtain two kinds of precipitation slag of strontium vanadate and strontium tungstate. Further, decomposing strontium vanadate by using a sodium carbonate solution to obtain a sodium vanadate solution and strontium carbonate; decomposing strontium tungstate by using a hydrochloric acid solution to obtain tungstic acid and strontium chloride. The solution after acid decomposition contains strontium chloride and hydrochloric acid, and is directly returned to the precipitation process to consume sodium hydroxide in the solution. Therefore, the strontium carbonate slag and the sodium carbonate solution obtained in the process are utilized to neutralize the hydrochloric acid in the solution after acid decomposition, and the neutral strontium chloride solution which can be used again is obtained. The solution after tungsten precipitation contains excessive sodium hydroxide, so that the solution can be returned to the leaching process for recycling. After multiple cycles, the concentration of sodium chloride in the solution after tungsten precipitation is increased cumulatively, so that the sodium chloride in the solution needs to be removed by adopting an evaporation crystallization mode.
The invention has the following beneficial effects:
the invention is a full wet processing technology, the material recycling rate in the system is high, which is shown in the following steps: and water recycling, strontium salt recycling, sodium hydroxide surplus in dissolution reaction recycling, and sodium carbonate obtained by recycling in the process is also used for acid-base neutralization reaction. The reagents mainly consumed in the whole process are hydrochloric acid and sodium hydroxide, and the final product sodium chloride is produced in a crystallized form in the system without waste water discharge. After the waste SCR catalyst is decomposed, main valuable elements of titanium, tungsten and vanadium are respectively recovered, and the obtained high-titanium slag, tungstic acid 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 waste SCR denitration catalyst, which comprises the following steps:
(1) mixing a waste SCR 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 waste SCR denitration catalyst is a vanadium-titanium denitration catalyst and comprises oxygen, titanium, tungsten, vanadium and molybdenum; the dissolving agent is one or more of a sodium hydroxide solution, a tungsten precipitation solution obtained in the step (5), a desalted solution obtained in the step (6);
(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 chloride or the neutral strontium chloride solution obtained in the step (9) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out vanadium precipitation reaction at a certain temperature, and carrying out solid-liquid separation to obtain vanadium precipitation liquid and strontium vanadate slag;
(5) mixing strontium chloride or the neutral strontium chloride solution obtained in the step (9) with the vanadium-precipitated solution obtained in the step (4) according to a certain proportion, performing tungsten precipitation reaction at a certain temperature, and performing solid-liquid separation to obtain tungsten-precipitated solution and strontium tungstate slag;
(6) when the concentration of sodium chloride in the tungsten-precipitated liquid obtained in the step (5) is more than 150g/L, carrying out evaporation crystallization operation on the tungsten-precipitated liquid, collecting condensed water, and obtaining desalted liquid and sodium chloride crystals;
(7) mixing the strontium vanadate slag obtained in the step (4) with a sodium carbonate solution, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a sodium vanadate solution and strontium carbonate slag;
(8) mixing the strontium tungstate residue obtained in the step (5) with a hydrochloric acid solution, carrying out acid decomposition reaction at a certain temperature, and carrying out solid-liquid separation to obtain tungstic acid and a solution after acid decomposition;
(9) and (4) adding the strontium carbonate slag obtained in the step (7) and/or the sodium carbonate solution obtained in the step (3) into the acid decomposed liquid obtained in the step (8), and performing neutralization reaction to obtain a neutral strontium chloride solution.
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
3kg 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.% is mixed with tungsten precipitation liquid with sodium hydroxide content of 16 wt.%, the liquid-solid ratio is 5, the oil bath temperature is 130 ℃, stirring and dissolving are carried out for 5 hours, and the contents of sodium, tungsten, molybdenum and vanadium in dissolved slag obtained after filtering, water washing and drying are respectively 3.3 wt.%, 0.17 wt.%, 0.09 wt.% and 0.13 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 6 hours, the sodium content in the sodium-removed high titanium slag was 0.43 wt.% (dry basis).
And equally dividing the dissolved liquid into 5 parts, adding strontium chloride according to different conditions to carry out vanadium precipitation reaction, analyzing the concentration of vanadium in the solution after the reaction is finished to obtain vanadium precipitation rate, and analyzing the concentration of tungsten in slag to obtain tungsten precipitation rate. The test conditions and results are shown in the following table.
Example 3
5kg of waste SCR denitration catalyst powder with titanium, tungsten and vanadium contents of 42.55 wt.%, 3.85 wt.% and 0.45 wt.% respectively is mixed with desalted liquid with sodium hydroxide content of 26 wt.%, the liquid-solid ratio is 3.5, the oil bath temperature is 150 ℃, stirring and dissolving are carried out for 4 hours, and the contents of sodium, tungsten and vanadium in dissolved slag obtained after filtering, washing and drying are respectively 4.9 wt.%, 0.21 wt.% and 0.22 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 12 hours of leaching, the sodium content in the sodium-removed high titanium slag was 0.31 wt.% (dry basis).
Heating the dissolution liquid to 90 ℃, slowly dropwise adding a strontium chloride solution under the stirring state, wherein the adding amount of the strontium chloride is 2.5 times of the molar amount of vanadium in the dissolution liquid, stirring for reacting for 55 minutes, and performing solid-liquid separation to obtain strontium vanadate slag and a vanadium precipitation liquid. The analysis result shows that the vanadium precipitation rate is 91 percent, and the tungsten precipitation rate is 0.8 percent.
Equally dividing the strontium vanadate slag into 5 parts, respectively mixing with a sodium carbonate solution, carrying out carbonation reaction according to different conditions, and measuring the vanadium content in the slag before and after conversion, thereby calculating the conversion rate of strontium vanadate into strontium carbonate.
The test conditions and results are shown in the following table.
Equally dividing the solution after vanadium precipitation into 4 parts, adding strontium chloride according to different conditions to carry out tungsten precipitation reaction, and analyzing the concentration of tungsten in the solution after the reaction is finished to obtain the tungsten precipitation rate. The test conditions and results are shown in the following table.
Example 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.% is mixed with 23 wt.% sodium hydroxide solution, the liquid-solid ratio is 4.5, the oil bath temperature is 120 ℃, stirring and dissolving are carried out for 4 hours, and the contents of sodium, tungsten, molybdenum and vanadium in dissolved slag obtained after filtering, water washing and drying are 1.9 wt.%, 0.19 wt.%, 0.10 wt.% and 0.08 wt.% respectively.
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 was 0.23 wt.% (dry basis).
Heating the dissolution liquid to 95 ℃, slowly dropwise adding a strontium chloride solution under the stirring state, wherein the adding amount of the strontium chloride is 2 times of the molar amount of vanadium in the dissolution liquid, stirring for reacting for 60 minutes, and performing solid-liquid separation to obtain strontium vanadate slag and a vanadium precipitation liquid. The analysis result shows that the vanadium precipitation rate is 89%, and the tungsten precipitation rate is 0.6%.
Heating the solution after vanadium precipitation to 90 ℃, adding a strontium chloride solution under a stirring state, wherein the addition amount of the strontium chloride is 1.1 times of the molar amount of tungsten in the solution after vanadium precipitation, stirring for reacting for 60 minutes, and carrying out solid-liquid separation to obtain strontium tungstate slag and the solution after tungsten precipitation. The analysis result shows that the tungsten deposition rate is 96 percent. Equally dividing the strontium tungstate slag into 3 parts, adding hydrochloric acid according to different conditions to perform acid decomposition reaction, analyzing the content of strontium remaining in the tungstic acid after the reaction is finished, and calculating the decomposition rate. The test conditions and results are shown in the following table.
And (3) enriching a small amount of vanadium in the strontium tungstate slag in the acid solution through an acid decomposition process, so that tungsten and vanadium are deeply separated. The vanadium content in 3 parts of tungstic acid is less than 0.1 wt.%.
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 (8)
1. A method for respectively recovering titanium, tungsten and vanadium from a waste SCR denitration catalyst is characterized by comprising the following steps:
(1) mixing a waste SCR 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 waste SCR denitration catalyst is a vanadium-titanium denitration catalyst and comprises oxygen, titanium, tungsten, vanadium and molybdenum; the dissolving agent is one or more of a sodium hydroxide solution, a tungsten precipitation solution obtained in the step (5), a desalted solution obtained in the step (6);
(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 chloride or the neutral strontium chloride solution obtained in the step (9) with the dissolution liquid obtained in the step (1) according to a certain proportion, carrying out vanadium precipitation reaction at a certain temperature, and carrying out solid-liquid separation to obtain vanadium precipitation liquid and strontium vanadate slag;
(5) mixing strontium chloride or the neutral strontium chloride solution obtained in the step (9) with the vanadium-precipitated solution obtained in the step (4) according to a certain proportion, performing tungsten precipitation reaction at a certain temperature, and performing solid-liquid separation to obtain tungsten-precipitated solution and strontium tungstate slag;
(6) when the concentration of sodium chloride in the tungsten-precipitated liquid obtained in the step (5) is more than 150g/L, carrying out evaporation crystallization operation on the tungsten-precipitated liquid, collecting condensed water, and obtaining desalted liquid and sodium chloride crystals;
(7) mixing the strontium vanadate slag obtained in the step (4) with a sodium carbonate solution, carrying out carbonation reaction at a certain temperature, and carrying out solid-liquid separation to obtain a sodium vanadate solution and strontium carbonate slag;
(8) mixing the strontium tungstate residue obtained in the step (5) with a hydrochloric acid solution, carrying out acid decomposition reaction at a certain temperature, and carrying out solid-liquid separation to obtain tungstic acid and a solution after acid decomposition;
(9) and (4) adding the strontium carbonate slag obtained in the step (7) and/or the sodium carbonate solution obtained in the step (3) into the acid decomposed liquid obtained in the step (8), and performing neutralization reaction to obtain a neutral strontium chloride solution.
2. The method for separately recovering titanium, tungsten and vanadium from a waste 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 recovering titanium, tungsten and vanadium from a waste SCR denitration catalyst according to claim 1, wherein the solid-to-solid ratio of the leaching reaction solution in the step (1) is 3 to 7, the leaching temperature is 110 to 150 ℃, and the leaching time is 2 to 7 hours.
4. The method for respectively recovering titanium, tungsten and vanadium from the waste SCR denitration catalyst as claimed in claim 1, wherein the amount of strontium chloride used in the vanadium precipitation reaction in the step (4) is 1.5-3 times of the molar amount of vanadium in the dissolution liquid, the reaction temperature is 80-100 ℃, and the reaction time is 0.5-1.0 hour.
5. The method for respectively recovering titanium, tungsten and vanadium from a waste SCR denitration catalyst as claimed in claim 1, wherein the amount of strontium chloride used in the tungsten precipitation reaction in the step (5) is 0.8-1.2 times of the molar amount of tungsten in the solution after vanadium precipitation, 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 waste SCR denitration catalyst according to claim 1, wherein the sodium carbonate used in the carbonation reaction of the step (7) is 1.5 to 3.0 times of the molar amount of strontium in strontium vanadate slag, the reaction temperature is 110 to 140 ℃, and the reaction time is 0.5 to 1.0 hour.
7. The method for respectively recovering titanium, tungsten and vanadium from the waste SCR denitration catalyst as claimed in claim 1, wherein the amount of hydrochloric acid used in the acid decomposition reaction in the step (8) is 10-16 times of the molar weight of strontium in the strontium tungstate slag, the reaction temperature is above 70 ℃, and the reaction time is 0.5-1.5 hours.
8. The method for separately recovering titanium, tungsten and vanadium from a waste SCR denitration catalyst according to claim 1, wherein the step (1) is performed with a leaching reaction while collecting condensed water, and the condensed water is used for water washing of the step (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011167044.5A CN112143903B (en) | 2020-10-27 | 2020-10-27 | Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011167044.5A CN112143903B (en) | 2020-10-27 | 2020-10-27 | Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112143903A CN112143903A (en) | 2020-12-29 |
| CN112143903B true CN112143903B (en) | 2022-04-12 |
Family
ID=73955016
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011167044.5A Active CN112143903B (en) | 2020-10-27 | 2020-10-27 | Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112143903B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102936049A (en) * | 2012-11-26 | 2013-02-20 | 西南民族大学 | Method for extracting tungsten, titanium and vanadium from waste SCR (selective catalytic reduction) 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 |
| CN107459059A (en) * | 2017-08-22 | 2017-12-12 | 河钢股份有限公司承德分公司 | A kind of method that tungsten vanadium is realized from discarded SCR denitration and is efficiently carried altogether |
| CN107904403A (en) * | 2017-10-31 | 2018-04-13 | 钢研晟华科技股份有限公司 | A kind of method of vanadium titanium system denitration dead catalyst comprehensive reutilization |
| CN110468278A (en) * | 2019-09-09 | 2019-11-19 | 中南大学 | A method of handling useless denitrating catalyst |
-
2020
- 2020-10-27 CN CN202011167044.5A patent/CN112143903B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102936049A (en) * | 2012-11-26 | 2013-02-20 | 西南民族大学 | Method for extracting tungsten, titanium and vanadium from waste SCR (selective catalytic reduction) 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 |
| CN107459059A (en) * | 2017-08-22 | 2017-12-12 | 河钢股份有限公司承德分公司 | A kind of method that tungsten vanadium is realized from discarded SCR denitration and is efficiently carried altogether |
| CN107904403A (en) * | 2017-10-31 | 2018-04-13 | 钢研晟华科技股份有限公司 | A kind of method of vanadium titanium system denitration dead catalyst comprehensive reutilization |
| CN110468278A (en) * | 2019-09-09 | 2019-11-19 | 中南大学 | A method of handling useless denitrating catalyst |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112143903A (en) | 2020-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104195342B (en) | A kind of method reclaiming Vanadium Pentoxide in FLAKES composition in waste and old SCR denitration | |
| CN103526031A (en) | Recovery method for SCR waste flue gas denitration catalyst | |
| CN110217810B (en) | Method for efficiently recovering valuable elements in aluminum ash | |
| CN111020193B (en) | Method for recovering vanadium, tungsten and titanium elements from waste SCR denitration catalyst | |
| CN111170299B (en) | Method for recovering waste cathode carbon blocks from aluminum electrolysis | |
| CN105274341A (en) | Method for leaching metallic vanadium and metallic tungsten in waste selective catalytic reduction (SCR) denitration catalyst | |
| CN114774701B (en) | Resource utilization method of industrial waste salt and waste denitration catalyst | |
| CN114671636A (en) | Method for harmless treatment of secondary aluminum ash by alkalescent water washing | |
| CN107352819A (en) | A kind of aluminium cell carbonaceous waste material is used for the method for producing calcium aluminum fluoride clinker | |
| CN107185554A (en) | A kind of method that useless SCR denitration cleaning is recycled | |
| CN102974182B (en) | Method for treating smelting flue gas containing secondary zinc oxide | |
| CN107363074B (en) | A kind of aluminium cell carbonaceous materials recycling is the method for alternative fire coal | |
| CN105457491A (en) | Separating and recycling method of abandoned coal-fired boiler flue gas denitration catalyst | |
| CN102260801A (en) | Clean conversion method of stone coal | |
| CN111996379B (en) | Method for recovering valuable metal from waste SCR denitration catalyst | |
| CN103264991A (en) | Method for processing sulfur paste as coke oven gas desulfuration by-product | |
| CN112143902B (en) | Method for respectively recovering titanium, tungsten and vanadium from invalid SCR denitration catalyst | |
| CN114733888A (en) | Method and system for comprehensively utilizing secondary aluminum ash | |
| CN112342392B (en) | Method for respectively recovering titanium, tungsten and vanadium from waste denitration catalyst | |
| US20200290889A1 (en) | Method for producing vanadate | |
| CN107159688B (en) | A kind of aluminium cell carbonaceous materials recycling is made a living the method for producing electricity stone raw material | |
| CN113877591A (en) | Preparation method of acid-treated iron mud denitration catalyst | |
| CN112143903B (en) | Method for respectively recovering titanium, tungsten and vanadium from waste SCR denitration catalyst | |
| CN112143901B (en) | Method for respectively recovering titanium, tungsten and vanadium from vanadium-titanium waste denitration catalyst | |
| CN108516569B (en) | Method for preparing lithium sulfate solution by roasting lepidolite |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |