CN113457674B - Improve Pt-CeO 2 Method for low temperature activity and durability of catalyst oxidation reaction - Google Patents
Improve Pt-CeO 2 Method for low temperature activity and durability of catalyst oxidation reaction Download PDFInfo
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Abstract
The invention relates to a method for improving Pt-CeO 2 A method for low temperature activity and durability of a catalyst oxidation reaction comprising the steps of: A. dripping a platinum source solution on the surface of a cerium oxide carrier, and drying to obtain a catalyst a; B. heating the catalyst a to 350-500 ℃, keeping the temperature for 2-6h, cooling to room temperature, then heating to 650-800 ℃, keeping the temperature for 6-20 h; C. taking catalyst b in H 2 Reducing under the atmosphere; D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor; E. treating the catalyst d with a specific atmosphere; F. treating for 1-3 times according to the method of the steps C-E; G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor; H. adding catalyst g in H 2 Reducing for 10-30min under atmosphere. The invention can improve Pt-CeO 2 The catalyst has low-temperature activity and durability in oxidation reaction.
Description
Technical Field
The invention relates to the field of catalyst modification, in particular to a method for improving low-temperature activity and durability of a Pt-CeO2 catalyst in an oxidation reaction.
Background
In recent years, it has been found that rare earth oxides have some specific catalytic effects, among which cerium oxide is an effective oxidation catalyst support, which in combination with platinum can enhance the reactivity. However, the current Pt/CeO2 catalyst has two main drawbacks: 1. the low-temperature activity is poor, namely the conversion capability of pollutants such as CO and HC (hydrocarbon) is weak at low temperature (such as a cold start stage of a motor vehicle), so that the emission of pollutants is caused, and the environment is polluted; 2. the durability is poor, namely the catalyst is easy to oxidize and deactivate active components under the oxygen-rich atmosphere, and the service life is short.
Disclosure of Invention
The invention aims to provide a method for improving the low-temperature activity and durability of the oxidation reaction of a Pt-CeO2 catalyst, which can regulate the chemical state of Pt, prevent the catalyst from being oxidized in an oxygen-rich atmosphere, further improve the activity and durability of the catalyst, reduce the complete conversion temperature of reactants by steam treatment and improve the low-temperature activity of the catalyst.
The purpose of the invention is realized by the following technical scheme:
the improvement of Pt-CeO 2 A method for low temperature activity and durability of a catalyst oxidation reaction comprising the steps of:
A. dissolving a platinum source in water to prepare a solution, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method, and drying to obtain a catalyst a;
B. heating the catalyst a to 350-500 ℃, keeping the temperature for 2-10h, cooling to room temperature, then heating to 650-800 ℃, keeping the temperature for 6-20 h to obtain a catalyst b;
C. taking the catalyst b and using 80-160mL/min 3-7%H at 300-450 DEG C 2 Reducing for 10-30min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 1-30min to obtain a catalyst d;
E. treating the catalyst d at 160-260 ℃ for 0.2-6h by using a specific atmosphere to obtain a catalyst e; the specific atmosphere comprises one of the following components: CO 2 2 By Ar or N 2 Equilibrium, CO + O 2 By Ar or N 2 Balance,C 3 H 6 +O 2 By Ar or N 2 Balancing; F. treating the catalyst E for 1-3 times according to the method in the steps C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 1-30min to obtain a catalyst g;
H. taking catalyst g, and using 80-160mL/min 3-7%H at 300-450 DEG C 2 Reducing for 10-30min under Ar atmosphere.
In the step A, the platinum source is chloroplatinic acid hexahydrate.
The concentration of the platinum aqueous solution in the step A is as follows: the concentration of chloroplatinic acid hexahydrate is 5-12g/L; the dripping time is 10-30min.
The drying temperature in the step A is 70-90 ℃.
In the step D, the temperature of the water vapor flowing through the surface of the catalyst c is 40-80 ℃; in the step G, the temperature of the water vapor flowing through the surface of the catalyst f is 40-80 ℃.
The specific atmosphere in the step E comprises the following components:
2% -10% of CO 2 Atmosphere with Ar or N 2 Balancing, wherein the total flow is 100-200mL/min;
or 0.5-1.5% by weight of CO +1-2%O 2 Mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 300-500mL/min;
or 0.05-0.25% 3 H 6 +3-6％O 2 Mixed atmosphere with Ar or N 2 Balance, total flow rate is 100-200mL/min.
In the step B, the temperature rise speed of the catalyst a is 3-10 ℃/min in the process of heating to 300-450 ℃; then the heating speed is 5-15 ℃/min in the process of heating to 650-800 ℃.
And H, after the step H is finished, the loading content of platinum on the surface of the cerium oxide carrier is 0.3-2.5%.
The invention loads Pt on CeO by an isovolumetric impregnation method 2 In the above way, the chemical state and chemical environment of Pt can be regulated and controlled through multiple times of specific atmosphere and water vapor treatment, so that the catalyst is prevented from being oxidized in an oxygen-rich atmosphere, and the activity and durability of the catalyst are further improved.
Tests show that the Pt-CeO treated by the method of the invention 2 The catalyst has high activity and durability for oxidation reaction of CO or mixed atmosphere of CO and HC (hydrocarbon).
Drawings
FIG. 1 is a CO oxidation reaction activity test chart;
FIG. 2 is a CO oxidation reaction durability test chart;
FIG. 3 is a graph showing the oxidation activity of 0.5% by weight of Pt-CeO2-750 in a mixed atmosphere;
FIG. 4 is a graph showing the durability of the oxidation reaction in a mixed atmosphere of 0.5% by weight of Pt-CeO 2-750;
Detailed Description
The invention is further illustrated by the following examples. It should be understood that the examples of the present invention are for illustrative purposes and not intended to limit the present invention. Simple modifications of the invention in accordance with its spirit fall within the scope of the claimed invention.
Example 1
Increasing Pt-CeO 2 A method for low temperature activity and durability of a catalyst oxidation reaction comprising the steps of:
A. dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method, and drying at 70 ℃ to obtain a catalyst a, wherein the concentration of the chloroplatinic acid hexahydrate is 5 g/L;
B. heating the catalyst a to 350 ℃ at a heating rate of 3 ℃/min, keeping the temperature for 2 hours, cooling to room temperature, heating to 650 ℃ at a heating rate of 5 ℃/min, and keeping the temperature for 6 hours to obtain a catalyst b;
C. taking the catalyst b at 300 ℃ and using 80mL/min 3%H 2 Reducing for 10min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 2min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 40-50 ℃;
E. treating the catalyst d for 0.5h at 160 ℃ in a specific atmosphere to obtain a catalyst e; the specific atmosphere is 0.5% by weight of CO +1％O 2 Mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 300mL/min;
F. treating the catalyst E for 1 time according to the method in the steps C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 2min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 40-50 ℃;
H. taking catalyst g and using 80mL/min 3%H at 300 DEG C 2 Reducing for 10min under Ar atmosphere to obtain the final product.
Example 2
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 12g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 30min, and drying at 90 ℃ to obtain a catalyst a;
B. heating the catalyst a to 450 ℃ at a heating rate of 10 ℃/min, keeping the temperature for 10 hours, cooling to room temperature, heating to 800 ℃ at a heating rate of 15 ℃/min, and keeping the temperature for 20 hours to obtain a catalyst b;
C. taking catalyst b at 450 ℃ and using 160mL/min 7%H 2 Reducing for 30min under Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 30min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 70-80 ℃;
E. treating the catalyst d for 6 hours at 260 ℃ in a specific atmosphere to obtain a catalyst e;
the specific atmosphere comprises the following components:
10% CO 2 Atmosphere with Ar or N 2 Balancing, wherein the total flow is 200mL/min;
F. treating the catalyst E for 3 times according to the method in the steps C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 30min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 70-80 ℃;
H. taking catalyst g at 450 DEG CUsing 160mL/min 3%H 2 Reducing for 30min under Ar atmosphere to obtain the final product.
Example 3
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 8g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 20min, and drying at 80 ℃ to obtain a catalyst a;
B. heating the catalyst a to 400 ℃ at a heating rate of 5 ℃/min, keeping the temperature for 5 hours, cooling to room temperature, heating to 720 ℃ at a heating rate of 10 ℃/min, and keeping the temperature for 12 hours to obtain a catalyst b;
C. taking the catalyst b at 400 ℃ and using 120mL/min 5%H 2 Reducing for 20min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 20min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 50-60 ℃;
E. treating the catalyst d for 3 hours at 200 ℃ in a specific atmosphere to obtain a catalyst e;
the specific atmosphere comprises the following components:
5% CO 2 Atmosphere with Ar or N 2 Balancing, wherein the total flow is 150mL/min;
F. treating the catalyst E for 2 times according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 20min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 50-60 ℃;
H. taking catalyst g, and using 120mL/min 3%H at 400 DEG C 2 Reducing for 20min under Ar atmosphere to obtain the final product.
Example 4
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 6g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 12min, and drying at 75 ℃ to obtain a catalyst a;
B. heating the catalyst a to 320 ℃ at the heating rate of 4 ℃/min, keeping the temperature for 7 hours, cooling to room temperature, then heating to 730 ℃ at the heating rate of 12 ℃/min, keeping the temperature for 9 hours, and obtaining a catalyst b;
C. taking the catalyst b at 410 ℃ and using 150mL/min 6%H 2 Reducing for 12min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 6min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 60-70 ℃;
E. treating the catalyst d for 1h at 220 ℃ in a specific atmosphere to obtain a catalyst e;
0.5％CO+1％O 2 mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 300mL/min;
F. treating the catalyst E for 1 time according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 12min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 40-50 ℃;
H. taking catalyst g and using 140mL/min 3%H at 340 DEG C 2 Reducing for 25min under Ar atmosphere to obtain the final product.
Example 5
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 11g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 25min, and drying at 75 ℃ to obtain a catalyst a;
B. heating the catalyst a to 410 ℃ at a heating rate of 6 ℃/min, keeping the temperature for 8 hours, cooling to room temperature, heating to 680 ℃ at a heating rate of 9 ℃/min, and keeping the temperature for 13 hours to obtain a catalyst b;
C. catalyst b was sampled at 360 ℃ with 140mL/min 6%H 2 Reducing for 23min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 29min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 40-50 ℃;
E. treating the catalyst d for 1.6h at 170 ℃ in a specific atmosphere to obtain a catalyst e;
the specific atmosphere comprises the following components:
1.5％CO+2％O 2 mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 500mL/min;
F. treating the catalyst E for 3 times according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 26min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 50-60 ℃;
H. taking catalyst g and using 110mL/min 3%H at 370 DEG C 2 Reducing for 17min under Ar atmosphere to obtain the final product.
Example 6
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 7g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 21min, and drying at 80 ℃ to obtain a catalyst a;
B. heating the catalyst a to 400 ℃ at a heating rate of 5 ℃/min, keeping the temperature for 4 hours, cooling to room temperature, heating to 750 ℃ at a heating rate of 10 ℃/min, and keeping the temperature for 10 hours to obtain a catalyst b;
C. taking the catalyst b at 400 ℃ and using 100mL/min 5%H 2 Reducing for 20min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 2min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 50-60 ℃;
E. treating the catalyst d for 2 hours at 160-260 ℃ in a specific atmosphere of 80-160mL/min to obtain a catalyst e;
the specific atmosphere comprises the following components:
1％CO+2％O 2 mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 500mL/min;
F. treating the catalyst E for 2 times according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 2min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 50-60 ℃;
H. taking catalyst g and using 100mL/min 3%H at 400 DEG C 2 Reducing for 20min under Ar atmosphere to obtain the final product.
Example 7
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 10g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 18min, and drying at 73 ℃ to obtain a catalyst a;
B. heating the catalyst a to 350 ℃ at a heating rate of 4 ℃/min, keeping the temperature for 3 hours, cooling to room temperature, heating to 670 ℃ at a heating rate of 11 ℃/min, and keeping the temperature for 15 hours to obtain a catalyst b;
C. taking the catalyst b at 380 ℃ and using 4%H of 90mL/min 2 Reducing for 13min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 4min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 45-55 ℃;
E. treating the catalyst d for 4 hours at 200 ℃ in a specific atmosphere of 140mL/min to obtain a catalyst e;
the specific atmosphere comprises the following components:
0.05％C 3 H 6 +3％O 2 mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 100mL/min;
F. treating the catalyst E for 1 time according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 20min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f was 50 ℃;
H. taking catalyst g, and using 150mL/min 3%H at 360 DEG C 2 Reducing for 14min under Ar atmosphere to obtain the product.
Example 8
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 7g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 29min, and drying at 81 ℃ to obtain a catalyst a;
B. heating the catalyst a to 360 ℃ at a heating rate of 7 ℃/min, keeping the temperature for 6 hours, cooling to room temperature, heating to 770 ℃ at a heating rate of 13 ℃/min, and keeping the temperature for 17 hours to obtain a catalyst b;
C. taking catalyst b and using 125mL/min 5%H at 330 DEG C 2 Reducing for 18min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 17min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 65-75 ℃;
E. treating the catalyst d for 1h at 220 ℃ in a specific atmosphere of 120mL/min to obtain a catalyst e;
the specific atmosphere comprises the following components:
0.25％C 3 H 6 +6％O 2 mixed atmosphere with Ar or N 2 The balance is carried out, and the total flow is 200mL/min.
F. Treating the catalyst E for 2 times according to the method in the steps C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 26min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f is 60-70 ℃;
H. catalyst g was sampled at 330 ℃ and used 140mL/min 3%H 2 Reducing for 26min under Ar atmosphere to obtain the final product.
Example 9
A. Dissolving chloroplatinic acid hexahydrate in water to prepare a platinum solution, wherein the concentration of the chloroplatinic acid hexahydrate is 9g/L, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method for 13min, and drying at 73 ℃ to obtain a catalyst a;
B. heating the catalyst a to 390 ℃ at the heating rate of 6 ℃/min, keeping the temperature for 3 hours, cooling to room temperature, heating to 680 ℃ at the heating rate of 7 ℃/min, keeping the temperature for 12 hours to obtain a catalyst b;
C. catalyst b was removed at 430 ℃ and used at 130mL/min 4%H 2 Reducing for 27min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 8min to obtain a catalyst d; the temperature of the water vapor flowing through the surface of the catalyst c is 67-75 ℃;
E. treating the catalyst d for 5 hours at 190 ℃ in a specific atmosphere of 150mL/min to obtain a catalyst e;
the specific atmosphere comprises the following components:
or 0.1% by weight of C 3 H 6 +4％O 2 Mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 150mL/min;
F. treating the catalyst E for 2 times according to the method in the step C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 8min to obtain a catalyst g; the temperature of the water vapor flowing through the surface of the catalyst f was 70 ℃;
H. taking catalyst g, and using 130mL/min 3%H at 390 DEG C 2 Reducing for 16min under Ar atmosphere to obtain the final product.
Experimental example 1
1. Experimental methods and conclusions
CO Oxidation Activity test with test conditions of 1% CO +2% by volume 2 The total flow rate was 500mL/min, and the balance was Ar gas. The amount of catalyst used was 50mg. Sample preparation procedure the parameters were varied at steps D-F with reference to example 6 to obtain: the sample is not treated by water vapor plus specific atmosphere, the sample is treated by primary water vapor plus specific atmosphere, the sample is treated by secondary water vapor plus specific atmosphere, and the sample is treated by tertiary water vapor plus specific atmosphere; the processing conditions and results of each experimental sample are shown in FIGS. 1 and 2.
As shown in FIG. 1, the Pt-CeO2 catalyst with 0.5% (mass fraction) of loading was calcined at 750 ℃ to obtain 0.5Pt-CeO 2 750, the low-temperature activity of the catalyst after primary water vapor + specific atmosphere treatment is obviously improved compared with that of an untreated sample; the temperature for complete conversion of CO was reduced from 177 ℃ to 156 ℃.
As shown in fig. 2, the durability of the CO oxidation reaction of the catalyst after multiple treatments of water vapor + specific atmosphere is significantly improved; the time for the catalyst to maintain 100% conversion to CO after 3 steam + specific atmosphere treatments lasted 45.6h, whereas the time for the untreated sample to maintain 100% conversion to CO was only 37 minutes.
Experimental example 2
1. Experimental sample
Experimental groups: the sample of example 6 was taken and the tested Pt loading on the surface of the cerium oxide support was 1.51%. The catalyst test amount was 50mg.
Control group data: commercial catalyst of Toyota, the precious metal composition in the catalyst of 1.1% Pt +0.9% Pd +0.1Rh. The catalyst was tested in an amount of 50mg. The data source is as follows:
Jeong H,Lee G,Kim B S,et al.Fully Dispersed Rh Ensemble Catalyst To Enhance Low-Temperature Activity[J].Journal of the American Chemical Society,2018, 140(30):9558-9565.
2. experimental methods and conclusions
1. Mixed atmosphere oxidation activity test, test conditions were all 1% CO, 0.2% 3 H 6 And 0.2% of C 3 H 8 The total flow rate is 100mL/min, and the Ar gas is balanced.
The results of the tests, as shown in figure 3 and table 1 below, show the temperatures corresponding to 90% conversion of the various components of the mixed atmosphere, and it can be seen that the catalyst of the invention is still more active than the Toyota catalyst at lower noble metal levels.
TABLE 1 90% conversion temperature (. Degree. C.) of the components of the mixed atmosphere
Fig. 4 is a durability test of the experimental sample under a mixed atmosphere, and it can be seen that the catalyst activity does not significantly decay after 50 hours of the test.
The consumption of the precious metal in the sample is less than that of the catalyst of Toyota company, the sample does not contain expensive Rh metal, the cost is only 25 percent of that of the catalyst of Toyota company, and the method has wider market prospect.
2. The results of the comparison, based on the 100% conversion duration of the CO oxidation reaction with secondary steam and different specific atmosphere treatments, are given in table 2 below:
TABLE 2 CO Oxidation reaction 100% conversion duration for Secondary steam + different specific atmosphere treatments
As can be seen, the most preferred specific atmosphere is CO + O 2 And (4) mixing the atmosphere.
Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (8)
1. Improve Pt-CeO 2 A method for low temperature activity and durability of a catalyst oxidation reaction, comprising the steps of:
A. dissolving a platinum source in water to prepare a solution, dropwise adding the platinum solution onto a cerium oxide carrier by adopting an isometric impregnation method, and drying to obtain a catalyst a;
B. heating the catalyst a to 350-500 ℃, keeping the temperature for 2-10h, cooling to room temperature, then heating to 650-800 ℃, keeping the temperature for 6-20 h to obtain a catalyst b;
C. taking the catalyst b and using 80-160mL/min 3-7%H at 300-450 DEG C 2 Reducing for 10-30min under the Ar atmosphere to obtain a catalyst c;
D. carrying out water vapor treatment on the surface of the catalyst c by using circulating water vapor for 1-30min to obtain a catalyst d;
E. catalyst d was treated with a specific atmosphere at 160-260 ℃ 0.Obtaining a catalyst e after 2-6 h; the specific atmosphere comprises one of the following components: CO 2 2 By Ar or N 2 Balance, C 3 H 6 +O 2 By Ar or N 2 Balancing;
F. treating the catalyst E for 1-3 times according to the method of the steps C-E to obtain a catalyst f;
G. carrying out water vapor treatment on the surface of the catalyst f by using circulating water vapor for 1-30min to obtain a catalyst g;
H. taking catalyst g, and using 80-160mL/min 3-7%H at 300-450 DEG C 2 Reducing for 10-30min under Ar atmosphere.
2. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: in the step A, the platinum source is chloroplatinic acid hexahydrate.
3. The enhanced Pt-CeO of claim 2 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: the concentration of the platinum aqueous solution in the step A is as follows: the concentration of chloroplatinic acid hexahydrate is 5-12g/L; the dripping time is 10-30min.
4. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: the drying temperature in the step A is 70-90 ℃.
5. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: in the step D, the temperature of the water vapor flowing through the surface of the catalyst c is 40-80 ℃; in the step G, the temperature of the water vapor flowing through the surface of the catalyst f is 40-80 ℃.
6. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: the specific atmosphere in the step E comprises the following components:
2% -10% of CO 2 Atmosphere with Ar or N 2 Balancing, wherein the total flow is 100-200mL/min;
or 0.5-1.5% by weight of CO +1-2%O 2 Mixed atmosphere with Ar or N 2 Balancing, wherein the total flow is 300-500mL/min;
or 0.05-0.25% 3 H 6 +3-6%O 2 Mixed atmosphere with Ar or N 2 Balance, total flow rate is 100-200mL/min.
7. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by: in the step B, the temperature rise speed of the catalyst a is 3-10 ℃/min in the process of heating to 300-450 ℃; then the temperature rising speed is 5-15 ℃/min in the process of heating to 650-800 ℃.
8. The enhanced Pt-CeO of claim 1 2 A method for low temperature activity and durability of catalyst oxidation reactions, characterized by:
and H, after the step H is finished, the loading content of platinum on the surface of the cerium oxide carrier is 0.3-2.5%.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101415490A (en) * | 2006-03-28 | 2009-04-22 | 株式会社丰田中央研究所 | Exhaust-gas cleaning catalyst, its regeneration method, exhaust-gas cleaning apparatus and exhaust-gas cleaning method using it |
| JP2014504202A (en) * | 2010-11-24 | 2014-02-20 | ビーエーエスエフ コーポレーション | Diesel oxidation catalyst body and production and use thereof |
| CN107413336A (en) * | 2011-03-04 | 2017-12-01 | 优美科触媒日本有限公司 | Exhaust gas purification catalyst, its preparation method and the exhaust gas purifying method using the catalyst |
| CN108144608A (en) * | 2017-12-22 | 2018-06-12 | 安徽工业大学 | Carbon monoxide water-gas shift platinum based catalyst and preparation method |
| CN111215053A (en) * | 2018-11-26 | 2020-06-02 | 中国科学院大连化学物理研究所 | Supported monatomic dispersed noble metal catalyst and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5003954B2 (en) * | 2007-11-19 | 2012-08-22 | 株式会社豊田中央研究所 | Exhaust gas purification oxidation catalyst, production method thereof, and exhaust gas purification method using exhaust gas purification oxidation catalyst |
| JP2011147901A (en) * | 2010-01-22 | 2011-08-04 | Toyota Motor Corp | Exhaust gas purifying catalyst |
-
2021
- 2021-05-31 CN CN202110600522.5A patent/CN113457674B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101415490A (en) * | 2006-03-28 | 2009-04-22 | 株式会社丰田中央研究所 | Exhaust-gas cleaning catalyst, its regeneration method, exhaust-gas cleaning apparatus and exhaust-gas cleaning method using it |
| JP2014504202A (en) * | 2010-11-24 | 2014-02-20 | ビーエーエスエフ コーポレーション | Diesel oxidation catalyst body and production and use thereof |
| CN107413336A (en) * | 2011-03-04 | 2017-12-01 | 优美科触媒日本有限公司 | Exhaust gas purification catalyst, its preparation method and the exhaust gas purifying method using the catalyst |
| CN108144608A (en) * | 2017-12-22 | 2018-06-12 | 安徽工业大学 | Carbon monoxide water-gas shift platinum based catalyst and preparation method |
| CN111215053A (en) * | 2018-11-26 | 2020-06-02 | 中国科学院大连化学物理研究所 | Supported monatomic dispersed noble metal catalyst and preparation method thereof |
Non-Patent Citations (4)
| Title |
|---|
| Activation of surface lattice oxygen in single-atom Pt/CeO2 for low-temperature CO oxidation;Lei Nie et al.;《Science》;20171215;第358卷(第6369期);第1页摘要，第2页第3段，第4页倒数第1段，补充材料：催化剂制备 * |
| Tuning Pt-CeO2 interactions by high-temperature vapor-phase synthesis for improved reducibility of lattice oxygen;Xavier Isidro Pereira-Hernández et al.;《NATURE COMMUNICATIONS》;20190325;第10卷;第1-10页 * |
| 氧化铈载金催化剂的低温CO氧化反应性能研究;黄新松;《中国优秀硕士学位论文全文数据库 工程科技I辑》;20091215(第12期);第26页图3.5，第27页第3.3.1节不同后处理条件对VP50载金催化剂结构与性能的影响 * |
| 银负载量及反应气预处理对银催化剂上氢气中CO选择氧化反应的影响;曲振平等;《催化学报》;20020930;第23卷(第5期);第460-464页 * |
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