Summary of the invention
The invention provides a kind of nanometer Ti base montmorillonite Cu Preparation of catalysts method and the application in HC-SCR thereof.Adopt ion-exchange process to prepare the Cu-Ti-PILC catalyst with meso-hole structure, the aperture is 2.2-6.8nm, and specific area is 178-312m
2/ g.Wherein the quality percentage composition of Cu is 1-5wt%, tests simple, the simple operation, with low cost of used instrument.This Cu-Ti-PILC catalyst is applied to the selection Reduction of NO, under middle low temperature (150-350 ℃), N
2Yield more than 50-70%.
A kind of nanometer Ti base montmorillonite Cu Preparation of catalysts method of the present invention may further comprise the steps:
(1) preparation of pillaring agent
Get the precursor TiCl of a certain amount of Ti
4Join in the HCl solution of 0.5-2M, the mol ratio that makes Ti and HCl is 5-10, adds deionized water again under continue stirring, and 20-40 ℃ is stirred the pillaring agent that obtains stable transparent behind the 12-30h.
(2) preparation of montmorillonite suspension liquid
A certain amount of imvite is joined in the deionized water of 500ml, stir 12-30h, imvite is fully expanded at 20-60 ℃.
(3) preparation of Ti base montmorillonite
Under 20-60 ℃, step (1) solution is joined in step (2) suspension, this moment, the mass ratio of Ti and imvite was 5-30.After stirring 12-30h, filters centrifugally, wash with the removal chlorion with deionized water, dry 6-24h under 80-120 ℃ of temperature then is at last as in the Muffle furnace, at 300-700 ℃ of temperature lower calcination 3-8h.
(4) Preparation of catalysts
Copper presoma (as Schweinfurt green, copper nitrate, copper sulphate) is dissolved in the deionized water, makes active component solution.Add the Ti base montmorillonite carrier that step (3) makes then, once reach ion-exchange for several times, make that the quality percentage composition of copper is 1-5wt%.Solution after the ion-exchange filters centrifugal, spends deionised water for several times, and dry 6-24h under 80-120 ℃ of temperature again at 200-600 ℃ of temperature lower calcination 3-8h, just can obtain Ti base montmorillonite Cu catalyst.
The application of nanometer Ti base montmorillonite Cu catalyst in HC-SCR that above-mentioned preparation method obtains, the technical scheme of employing is: the volume ratio of hydro carbons (as the hydro carbons of methane, propylene, other kinds) reducing agent and NO is 1: 1, O
2Content be 8-15vol.%, air speed is 25000-45000h
-1, the active testing temperature is 150-350 ℃.The catalyst that the present invention makes is obtained the highest activity in the time of 250 ℃, at this moment N
2Yield can reach more than the 50-70%, have bigger prospects for commercial application.
Compared with prior art, the present invention has following advantage:
(1) the present invention is that raw material makes Ti base montmorillonite carrier with the imvite, and is simple to operate, with low cost, heat endurance is high, repeatability is high, can improve the anti-sulphur and the water repelling property of catalyst.
(2) prepared Ti base montmorillonite Cu catalyst have broad meso-hole structure (aperture is 2.2-6.8nm) and higher specific surface area (178-312m
2/ g).
(3) Zhi Bei Ti base montmorillonite Cu catalyst has higher catalyzing N O activity in the time of 150-350 ℃.
The specific embodiment
Be described in detail specific embodiments of the invention below in conjunction with technical scheme.
Embodiment 1
(1) preparation of pillaring agent
The HCl of 1M is solution-stabilized at 40 ℃, with the TiCl of 4.5ml
4Slowly be added drop-wise in the HCl solution, add deionized water again behind the stirring 1h, the cumulative volume that makes final solution is 100ml, obtains the pillaring agent of stable transparent behind the lasting stirring 24h.
(2) preparation of montmorillonite suspension liquid
The 4g imvite is joined in the deionized water of 500ml, stir 24h, imvite is fully expanded at 40 ℃.
(3) preparation of Ti base montmorillonite
Under 40 ℃, (1) solution slowly is added drop-wise in (2) suspension, this moment, the mass ratio of Ti and imvite was 10.After stirring 12-30h, filter centrifugally, wash, then at 80-120 ℃ temperature 6-24h, at last as in the Muffle furnace, at 450 ℃ temperature lower calcination 3-8h with deionized water.
(4) Preparation of catalysts
Schweinfurt green is dissolved in the deionized water, under continuing stirring, adds the Ti base montmorillonite carrier that makes in the step (3), filtration, centrifugal, washing.Repeat this process once, the quality percentage composition that can make copper is 4.2wt%.Solution after the ion-exchange filters centrifugal, spends deionised water for several times, and dry 6-24h under 80-120 ℃ of temperature at 400 ℃ of temperature lower calcination 3-8h, can obtain the catalyst finished product again.
Embodiment 2
As in the U type reactor, preliminary treatment 2h under 400 ℃ inert atmosphere is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 1
3H
6, 8vol.%, all the other are He, air speed is 25000h
-1), N in the time of 250 ℃
2Obtaining the highest yield is 72%.
Embodiment 3
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 1
3H
6, 10vol.%, all the other are He, air speed is 35000h
-1), N in the time of 250 ℃
2The highest yield be 61%.
Embodiment 4
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 1
3H
6, 15vol.%, all the other are He, air speed is 45000h
-1), N in the time of 250 ℃
2The highest yield be 48%
Embodiment 5
(1) preparation of pillaring agent
The HCl of 1M is solution-stabilized at 40 ℃, with the TiCl of 4.5ml
4Slowly be added drop-wise in the HCl solution, add deionized water again behind the stirring 1h, making final solution is 100ml, obtains the pillaring agent of stable transparent behind the lasting stirring 24h.
(2) preparation of montmorillonite suspension liquid
The 12g imvite is joined in the deionized water of 500ml, stir 24h, imvite is fully expanded at 60 ℃.
(3) preparation of Ti base montmorillonite
Under 60 ℃, step (1) solution is slowly dripped in step (2) suspension, this moment, the mass ratio of Ti and imvite was 30.After stirring 12-30h, filter centrifugally, wash, then at 80-120 ℃ temperature drying 6-24h, at last as in the Muffle furnace, at 700 ℃ temperature lower calcination 3-8h with deionized water.
(4) Preparation of catalysts
Schweinfurt green is dissolved in deionized water, is continuing to add the Ti base montmorillonite carrier that step (3) makes under the stirring, filtration, centrifugal, washing.Repeat this process once, the quality percentage composition that can make copper is 2.6wt%.Solution after the ion-exchange filters centrifugal, spends deionised water for several times, and dry 6h under 120 ℃ of temperature at 600 ℃ of temperature lower calcination 8h, can obtain the catalyst finished product again.
Embodiment 6
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 10vol.%, all the other are He, air speed is 25000h
-1), N in the time of 250 ℃
2The highest yield be 69%.
Embodiment 7
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppm C then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 10vol.%, all the other are He, air speed is 35000h
-1), N in the time of 250 ℃
2Obtaining the highest yield is 52%.
Embodiment 8
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 10vol.%, all the other are He, air speed is 45000h
-1), N in the time of 250 ℃
2Obtaining the highest yield is 42%.
Embodiment 9
(1) preparation of pillaring agent
The HCl of 1M is solution-stabilized at 40 ℃, with the TiCl of 4.5ml
4Slowly be added drop-wise in the HCl solution, add deionized water again behind the stirring 1h, making final solution is 100ml, obtains the pillaring agent of stable transparent behind the lasting stirring 24h.
(2) preparation of montmorillonite suspension liquid
The 2g imvite is joined in the deionized water of 500ml, stir 24h, imvite is fully expanded at 60 ℃.
(3) preparation of Ti base montmorillonite
Under 20 ℃, step (1) solution is slowly dripped in step (2) suspension, this moment, the mass ratio of Ti and imvite was 5.After stirring 12-30h, filters centrifugally, wash with the Cl ion in the removal solution, then at 80-120 ℃ temperature drying 6-24h, at last as in the Muffle furnace, at 300 ℃ temperature lower calcination 3-8h with deionized water.
(4) Preparation of catalysts
Schweinfurt green is dissolved in deionized water, is continuing to add the Ti base montmorillonite carrier that step (3) makes under the stirring, filtration, centrifugal, washing.Repeat this process once, the quality percentage composition that can make copper is 2.9wt%.Solution after the ion-exchange filters centrifugal, spends deionised water for several times, and dry 6h under 120 ℃ of temperature at 200 ℃ of temperature lower calcination 8h, can obtain the catalyst finished product again.
Embodiment 10
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 15vol.%, all the other are He, air speed is 25000h
-1), N in the time of 250 ℃
2The highest yield be 62%.
Embodiment 11
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppm C then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 15vol.%, all the other are He, air speed is 35000h
-1), N in the time of 250 ℃
2Obtaining the highest yield is 43%.
Embodiment 12
As in the U type reactor, preliminary treatment 2h under 400 ℃ of following inert atmospheres is reaction gas (1000ppmNO, 1000ppmC then with the preliminary treatment cyclostrophic with the catalyst 0.2g that makes among the embodiment 5
3H
6, 15vol.%, all the other are He, air speed is 45000h
-1), N in the time of 250 ℃
2Obtaining the highest yield is 31%.