Desulfurization, denitrification and mercury removal catalyst and preparation method thereof
阅读说明：本技术 一种脱硫脱硝除汞催化剂及其制备方法 (Desulfurization, denitrification and mercury removal catalyst and preparation method thereof ) 是由 郝宝玉 吴志玲 崔焕武 施园园 付秀云 吴立攀 于 2021-05-25 设计创作，主要内容包括：本发明公开了一种脱硫脱硝除汞催化剂及其制备方法。将钒酸盐与乙酸在去离子水中反应制成含钒络合物；将活性炭研磨过筛,然后将其浸泡在氢氧化钠溶液中,超声波分散处理后用去离子水清洗并干燥得到活性炭颗粒；将活性炭颗粒浸泡在含钒的络合物溶液中并超声处理,超声处理完毕后取出活性炭颗并进行煅烧得到钒炭基催化剂；将FeSO-(4)·7H-(2)O置于去离子水中配置成溶液,取钒炭基催化剂浸泡于上述溶液中并超声处理,超声处理后进行煅烧得到负载铁离子的钒炭基催化剂。本发明制备过程简单并且制备的催化剂脱硫脱硝除汞效果好,可以应用于烟气移动床实现烟气的脱硫脱硝除汞。(The invention discloses a desulfurization, denitrification and mercury removal catalyst and a preparation method thereof. Reacting vanadate with acetic acid in deionized water to prepare a vanadium-containing complex; grinding and sieving the activated carbon, then soaking the activated carbon in a sodium hydroxide solution, carrying out ultrasonic dispersion treatment, washing with deionized water and drying to obtain activated carbon particles; soaking activated carbon particles in vanadium-containing complex solutionCarrying out neutralization and ultrasonic treatment, taking out activated carbon particles after the ultrasonic treatment is finished, and calcining to obtain a vanadium-carbon-based catalyst; FeSO (ferric oxide) is added 4 ·7H 2 And placing the O in deionized water to prepare a solution, soaking the vanadium-carbon-based catalyst in the solution, performing ultrasonic treatment, and calcining the solution after the ultrasonic treatment to obtain the iron ion-loaded vanadium-carbon-based catalyst. The preparation process is simple, and the prepared catalyst has good desulfurization, denitrification and mercury removal effects, and can be applied to a flue gas moving bed to realize desulfurization, denitrification and mercury removal of flue gas.)
1. The preparation method of the desulfurization, denitrification and mercury removal catalyst is characterized by comprising the following steps:
(1) reacting vanadate with acetic acid in deionized water to prepare a vanadium-containing complex;
(2) grinding and sieving the activated carbon, then soaking the activated carbon in a sodium hydroxide solution, carrying out ultrasonic dispersion treatment, washing with deionized water and drying to obtain activated carbon particles;
(3) soaking the activated carbon particles in a vanadium-containing complex solution and carrying out ultrasonic treatment, taking out the activated carbon particles after the ultrasonic treatment is finished, and calcining to obtain a vanadium-carbon-based catalyst;
(4) FeSO (ferric oxide) is added4·7H2And placing the O in deionized water to prepare a solution, soaking the vanadium-carbon-based catalyst in the solution, performing ultrasonic treatment, separating out solids after the ultrasonic treatment is finished, and then calcining to obtain the iron ion-loaded vanadium-carbon-based catalyst.
2. The method according to claim 1, wherein in the step (1), the concentration of vanadium in the vanadium-containing complex solution is V2O5Meter, V2O5The mass concentration of (A) is 5-25%.
3. The method according to claim 2, wherein the vanadate is ammonium metavanadate or potassium metavanadate.
4. The preparation method according to claim 1, wherein in the step (2), the activated carbon is coconut shell activated carbon, and the grinding granularity is 30-40 meshes.
5. The preparation method according to claim 1, wherein in the step (3), the power of the ultrasonic treatment is 50kHz, and the time is 20-40 min.
6. The method according to claim 1, wherein in the step (3), the calcination is: under the protection of nitrogen, heating the activated carbon particles subjected to ultrasonic treatment from room temperature to 250-300 ℃ at the heating rate of 5 ℃/min, and calcining at the constant temperature of 250-300 ℃ for 2-3 h.
7. The method according to claim 1Characterized in that, in the step (4), FeSO4·7H2The dosage of O and ionized water is 1 g: (5-10) mL, FeSO4·7H2The mass ratio of O to the vanadium-carbon-based catalyst is greater than or equal to 2: 1; the ultrasonic treatment frequency is 50kHz, and the time is 20-40 min.
8. The method according to claim 1, wherein in the step (4), the calcination is: under the protection of nitrogen, the activated carbon particles after ultrasonic treatment are heated to 400-450 ℃ from room temperature at the heating rate of 5 ℃/min, and are calcined at the constant temperature of 400-450 ℃ for 4-5 h.
9. The desulfurization denitration demercuration catalyst prepared by the preparation method of any one of claims 1 to 8.
10. The use of the desulfurization, denitrification, mercury removal catalyst of claim 8 in a moving bed of flue gas.
Technical Field
The invention relates to the technical field of flue gas desulfurization, denitrification and mercury removal, and particularly relates to a desulfurization, denitrification and mercury removal catalyst and a preparation method thereof.
Background
Research on a moving bed technology for removing various pollutants in flue gas by dry integration is carried out in recent years by Shanxi coal chemistry research institute of Chinese academy of sciences, and the developed carbon-based catalyst realizes the dry integration removal of SO2, NOx and heavy metal in one reaction system, overcomes the defect that the stable operation of a coal-fired boiler is influenced by the disturbance of the flue gas pressure in the adsorption-regeneration switching process of a fixed bed reactor, and is particularly suitable for the integrated removal of multiple pollutants matched with a large coal-fired boiler. The catalyst used in the moving bed for removing various pollutants in flue gas by dry method integration is the vanadium-carbon-based catalyst, for example, the vanadium-carbon-based catalyst for desulfurization and denitrification and the preparation method and application thereof are disclosed in the Shanxi coal-carbon chemistry research institute of Chinese academy of sciences, application No. 201811576885.4, and the alkali metal-modified carbon-based catalyst for desulfurization and denitrification and the preparation method and application thereof are disclosed in the application No. 201811576884. X; the two catalysts are vanadium-carbon-based catalysts, but the preparation methods are complex, the preparation steps are more, and the desulfurization and denitrification effects are common. Therefore, a catalyst which is relatively simple in preparation method and good in desulfurization, denitrification and mercury removal effects is needed and can be applied to a flue gas moving bed to realize desulfurization, denitrification and mercury removal of flue gas.
Disclosure of Invention
Aiming at the prior art, the invention aims to provide a desulfurization, denitrification and mercury removal catalyst and a preparation method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a preparation method of a desulfurization, denitrification and mercury removal catalyst, which comprises the following steps:
(1) reacting vanadate with acetic acid in deionized water to prepare a vanadium-containing complex;
(2) grinding and sieving the activated carbon, then soaking the activated carbon in a sodium hydroxide solution, carrying out ultrasonic dispersion treatment, then washing with deionized water and drying to obtain activated carbon particles;
(3) soaking the activated carbon particles in a vanadium-containing complex solution and carrying out ultrasonic treatment, taking out the activated carbon particles after the ultrasonic treatment is finished, and calcining to obtain a vanadium-carbon-based catalyst;
(4) FeSO (ferric oxide) is added4·7H2And placing the O in deionized water to prepare a solution, soaking the vanadium-carbon-based catalyst in the solution, performing ultrasonic treatment, separating out solids after the ultrasonic treatment is finished, and then calcining to obtain the iron ion-loaded vanadium-carbon-based catalyst.
Preferably, in the step (1), the concentration of vanadium in the vanadium-containing complex solution is V2O5Meter, V2O5The mass concentration of (A) is 5-25%.
Preferably, the vanadate is ammonium metavanadate or potassium metavanadate.
Preferably, in the step (2), the activated carbon is coconut shell activated carbon, and the grinding granularity is 30-40 meshes.
Preferably, in the step (3), the power of the ultrasonic treatment is 50kHz, and the time is 20-40 min.
Preferably, in step (3), the calcination is: under the protection of nitrogen, heating the activated carbon particles subjected to ultrasonic treatment from room temperature to 250-300 ℃ at the heating rate of 5 ℃/min, and calcining at the constant temperature of 250-300 ℃ for 2-3 h.
Preferably, in step (4), FeSO4·7H2The dosage of O and ionized water is 1 g: (5-10) mL, FeSO4·7H2The mass ratio of O to the vanadium-carbon-based catalyst is greater than or equal to 2:1; the ultrasonic treatment frequency is 50kHz, and the time is 20-40 min.
Preferably, in step (4), the calcination is: under the protection of nitrogen, the activated carbon particles after ultrasonic treatment are heated to 400-450 ℃ from room temperature at the heating rate of 5 ℃/min, and are calcined at the constant temperature of 400-450 ℃ for 4-5 h.
In a second aspect of the invention, the desulfurization, denitrification and mercury removal catalyst prepared by the preparation method is provided.
In a third aspect of the invention, the application of the desulfurization, denitrification and mercury removal catalyst in a flue gas moving bed is provided.
The invention has the beneficial effects that:
the preparation method is simple, and the prepared catalyst is placed in a flue gas moving bed to realize desulfurization, denitrification and mercury removal of flue gas, and has a good effect. The catalyst has good effect of absorbing fine particles in smoke, and simultaneously V2O5The complex formed by the catalyst and acetic acid can effectively capture Hg degrees, and the catalyst can free iron ions to play a role in catalysis at a high temperature, so that the capture efficiency of Hg degrees is improved; the catalyst can also effectively desulfurize and denitrate, and is suitable for dry-method integrated removal of various pollutants in flue gas by a flue gas moving bed.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
When coal is combusted, due to the fact that the particle size of scattered coal is not uniform and even certain coal dust exists, air cannot penetrate through a coal bed uniformly under the influence of the thickness and the particle size of the coal bed under ordinary conditions, so that the air distribution in a hearth is not uniform, and an oxygen-enriched area and an oxygen-poor area are formed. In the oxygen-lean zone, combustion is incomplete because the fuel does not have sufficient oxygen to react with it. The molded coal has high purity, uniform granularity, good air permeability and uniform oxygen distribution; therefore, the desulfurization and denitrification of the molded coal are suitable for using a flue gas moving bed, the removal effect is good, but the mercury removal effect is general, so that a catalyst is neededThe mercury in the flue gas can be effectively removed while the desulfurization and the denitrification are carried out. Based on the above, the desulfurization, denitrification and mercury removal catalyst can be applied to desulfurization, denitrification and mercury removal of flue gas in a flue gas moving bed, and V2O5The complex formed by the catalyst and acetic acid can realize the capture of Hg degrees, and the catalyst can free iron ions to play a role in catalysis, thereby improving the capture efficiency of Hg degrees and playing an effective mercury removal role. Meanwhile, the catalyst can also effectively realize desulfurization and denitrification.
In order to make the technical solutions of the present application more clearly understood by those skilled in the art, the technical solutions of the present application will be described in detail below with reference to specific embodiments.
The test materials used in the examples of the present invention are all conventional in the art and commercially available.
Example 1:
(1) 76.8g of ammonium metavanadate was reacted with 64g of acetic acid in 90g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 30min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 50g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the activated carbon particles after the ultrasonic treatment is finished, heating the coconut shell activated carbon particles subjected to the ultrasonic treatment from room temperature to 300 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining at the constant temperature of 300 ℃ for 3h to obtain the vanadium-carbon-based catalyst.
(4) 100g of FeSO4·7H2Placing O in 800mL of deionized water to prepare a solution, soaking 50g of the vanadium-carbon-based catalyst in the solution, carrying out ultrasonic treatment at 50kHz for 30min, filtering the mixed solution by using a vacuum filter after the ultrasonic treatment is finished, heating the mixed solution to 400 ℃ from room temperature at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining at the constant temperature of 400 ℃ for 5h to obtain the iron ion-loaded vanadium-carbon-based catalyst.
Example 2
(1) 79.3g of potassium metavanadate was reacted with 64g of acetic acid in 180g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 20min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 100g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the coconut shell activated carbon particles after the ultrasonic treatment is finished, heating the coconut shell activated carbon particles subjected to the ultrasonic treatment from room temperature to 250 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining the coconut shell activated carbon particles at the constant temperature of 250 ℃ for 2h to obtain the vanadium-carbon-based catalyst.
(4) 200g of FeSO4·7H2Placing O in 1000mL of deionized water to prepare a solution, soaking 100g of vanadium-carbon-based catalyst in the solution, carrying out ultrasonic treatment at 50kHz for 30min, filtering the mixed solution by using a vacuum filter after the ultrasonic treatment is finished, heating the mixed solution to 450 ℃ from room temperature at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining at 450 ℃ for 4h at constant temperature to obtain the iron ion-loaded vanadium-carbon-based catalyst.
Comparative example 1
(1) 76.8g of ammonium metavanadate was reacted with 64g of acetic acid in 90g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 30min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 50g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the coconut shell activated carbon particles after the ultrasonic treatment is finished, heating the coconut shell activated carbon particles subjected to the ultrasonic treatment from room temperature to 400 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining the coconut shell activated carbon particles at the constant temperature of 400 ℃ for 5h to obtain the vanadium-carbon-based catalyst.
Comparative example 2
Prepared according to the method of example 1 in the patent application No. 201811576885.4:
(1) preparing coal powder: 600g of coking coal, 1200g of coke powder and 200g of dry bitumen are crushed, mixed and ground to a particle size of 200 mesh.
(2) Preparing a vanadium-containing complex solution by using 38.4g of ammonium metavanadate, 66g of oxalic acid and 195.6g of deionized water;
(3) preparing coal paste: adding the prepared coal powder, 374g of coal tar and the vanadium-containing complex solution into a kneader, and uniformly stirring and kneading to prepare coal paste.
(4) And (3) molding and granulating: molding and granulating the coal paste to prepare columnar particles;
(5) carbonizing: adding the formed columnar particles into a carbonization furnace, and carbonizing for 1 hour under the atmosphere of N2 to prepare a carbonized material;
(6) and (3) activation: and adding the prepared carbonized material into an activation furnace, and activating in a steam atmosphere to prepare the vanadium-carbon-based catalyst for low-temperature desulfurization and denitrification.
Comparative example 3
(1) 76.8g of ammonium metavanadate was reacted with 132g of oxalic acid in 90g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 30min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 50g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the coconut shell activated carbon particles after the ultrasonic treatment is finished, heating the coconut shell activated carbon particles subjected to the ultrasonic treatment from room temperature to 300 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining the coconut shell activated carbon particles at the constant temperature of 300 ℃ for 3h to obtain the vanadium-carbon-based catalyst.
Comparative example 4
(1) 76.8g of ammonium metavanadate was reacted with 132g of oxalic acid in 90g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 30min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 50g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the coconut shell activated carbon particles after the ultrasonic treatment is finished, heating the coconut shell activated carbon particles subjected to the ultrasonic treatment from room temperature to 300 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining the coconut shell activated carbon particles at the constant temperature of 300 ℃ for 3h to obtain the vanadium-carbon-based catalyst.
(4) 100g of FeSO4·7H2Placing O in 800mL of deionized water to prepare a solution, soaking 50g of the vanadium-carbon-based catalyst in the solution, carrying out ultrasonic treatment at 50kHz for 30min, filtering the mixed solution by using a vacuum filter after the ultrasonic treatment is finished, heating the mixed solution to 400 ℃ from room temperature at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining at the constant temperature of 400 ℃ for 5h to obtain the iron ion-loaded vanadium-carbon-based catalyst.
Comparative example 5
(1) 76.8g of ammonium metavanadate was reacted with 64g of acetic acid in 90g of deionized water to prepare a vanadium-containing complex solution.
(2) Grinding the coconut shell activated carbon to 30-40 meshes, sieving, soaking in a sodium hydroxide solution, performing ultrasonic dispersion treatment at 50kHz for 30min, washing twice with deionized water, and drying at 100 ℃ for 2h to obtain the coconut shell activated carbon particles.
(3) Soaking 50g of coconut shell activated carbon particles in a vanadium-containing complex solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the activated carbon particles after the ultrasonic treatment is finished, and drying at 100 ℃ for 5 h; 100g of FeSO4·7H2Placing O in 800mL deionized water to prepare a solution, soaking 50g of activated carbon particles in the solution, carrying out ultrasonic treatment at 50kHz for 30min, taking out the activated carbon particles after the ultrasonic treatment is finished, heating the activated carbon particles from room temperature to 400 ℃ at the heating rate of 5 ℃/min under the protection of nitrogen, and calcining the activated carbon particles at the constant temperature of 400 ℃ for 5h to obtain the iron ion-loaded vanadium-carbon-based catalyst.
Test examples
Mixing 70% of No. 1 raw coal, 20% of No. 1 coal slime and 10% of coal gangue according to mass percentage (the sulfur content is 2.0 wt%), drying, screening and crushing (60-80 meshes) to obtain a mixture, adding a binder (the binder consists of 21.56 wt% of sweet potato powder slag (dry basis), 1.08 wt% of sodium hydroxide and 77.36 wt% of water) accounting for 2% of the mass percentage of the mixture, and respectively carrying out mixing kneading, molding and drying (the molding pressure is 25MPa, the drying temperature is 130 ℃, and the drying time is more than or equal to 4.5 hours) to prepare molded coal.
The industrial data of the 1# raw coal, the 1# coal slime and the coal gangue are shown in the table 1 and the table 2.
TABLE 1 air-dried basis (wt%)
Table 2 elemental analysis data sheet (w% on dry basis)
Name (R)
N
C
H
S
O
Ad
No. 1 raw coal
1.03
61.96
3.90
2.53
0.89
29.70
1# coal slurry
0.71
42.75
3.00
0.87
7.66
45.01
Coal gangue
0.43
25.97
2.39
0.81
7.82
62.59
1 ton of the briquette is burned in the boiler each time, the generated flue gas is introduced into a flue gas moving bed (the structure of the flue gas moving bed is shown in a flue gas pollutant purification device disclosed in the patent with the application number of 201911094116.5), one catalyst in the examples 1-2 and the comparative examples 1-5 is filled in the reactor each time, and after 1 ton of the briquette is burned, the boiler is closed and the next catalyst is replaced. The catalysts prepared in examples 1-2 and comparative examples 1-5 were loaded in this way in sequence, and the other conditions of use of the flue gas moving bed were the same except that the catalysts were different. The using conditions of the catalyst are as follows: the reaction temperature is 100-180 ℃, and the volume space velocity is 200-800h-1、H2O content of 0 wt% -15 wt%, SO2The content is 800ppm for 100 and 500ppm for NO.
Through detection, the volume space velocity is 790h-1NO and H in the flue gas at the inlet2O、SO2And Hg DEG concentrations of 400ppm, 10%, 700ppm and 20ppm, respectively, and an oxygen content of 5%. Through detecting smoke at the mouthIn NO and SO2The removal rate of mercury (removal rate ═ concentration at inlet-outlet)/concentration at inlet 100%) was calculated from Hg ° concentration, and the results are shown in table 3.
TABLE 3
Desulfurization degree%
Denitration rate%
Mercury removal rate%
Example 1
98
96
93
Example 2
97
93
95
Comparative example 1
93
89
85
Comparative example 2
97
90
83
Comparative example 3
97
90
83
Comparative example 4
97
93
87
Comparative example 5
93
88
89
As can be seen from Table 3, the mercury removal rates of the catalysts of examples 1-2 are higher than those of comparative examples 1-5, and the maximum mercury removal rate can reach 95%. The mercury removal rate of the catalysts of comparative examples 1-5 is below 90%. The desulfurization and denitrification effects of the catalysts prepared in examples 1-2 are all more than 90%.
Therefore, the catalyst prepared by the invention can effectively perform desulfurization, denitrification and mercury removal through vanadate and acetic acid, and can free iron ions to play a role in catalysis at a high temperature by adding the iron-containing compound, so that the capture efficiency of Hg is improved.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种煤焦油制燃料油的催化剂及其制备方法