CN1189245C - Catalyst for car tail gas treatment and preparation thereof - Google Patents
Catalyst for car tail gas treatment and preparation thereof Download PDFInfo
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- CN1189245C CN1189245C CNB031209939A CN03120993A CN1189245C CN 1189245 C CN1189245 C CN 1189245C CN B031209939 A CNB031209939 A CN B031209939A CN 03120993 A CN03120993 A CN 03120993A CN 1189245 C CN1189245 C CN 1189245C
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- catalyst
- cordierite
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- vehicle exhaust
- molecular sieve
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Abstract
The present invention relates to a preparation method of a catalyst for treating automobile exhaust, particularly to a catalyst for eliminating NOx in the automobile exhaust. The catalyst is prepared by loading the active ingredients of the metals of Cu, Cu-La or Ag on a composite carrier of a molecular sieve formed by in situ synthesis on a cordierite carrier, wherein the loading amount of the active ingredient of Cu in the monolithic catalyst is 0.01 to 2 percent, and the loading amount of the active ingredient of La or Ag in the monolithic catalyst is 0.01 to 2 percent. Under the condition of no addition of any other substance, oxynitride as a contaminant can be reduced by selective reduction by the catalyst with the utilization of carbon monoxide and hydrocarbon in the automobile exhaust, and the oxynitride, the carbon monoxide and the hydrocarbon can be treated in integrated treatment. The catalyst has a wide range of application, and can be applied to a lean combustion condition, and maximum conversion rate to NOx in the exhaust gas of a lean combustion engine can reach 74.4 percent (a bench test with the airspeed of 11000 h<-1>); in addition, the catalyst has the advantages of high stability, long service life and good anti-poisoning property.
Description
Technical field
The present invention relates to be used for the Preparation of catalysts that vehicle exhaust is handled, it is to polluter NOx in the vehicle exhaust specifically, and HC and CO carry out the catalyst and the original position synthetic technology thereof of integrated treatment.
Background technology
Current, global ecological environment crisis is serious day by day, and wherein atmosphere pollution that nitrogen oxide caused and influence thereof are especially serious.At present nitrogen oxide is mainly from vehicle exhaust, and along with human lives's modernization and urbanization, the use of automobile is more and more general, and the discharge capacity of tail gas is increasing.Therefore, catalytic reaction is eliminated automobile exhaust pollution becomes a focus that is widely studied.Three-way catalyst (TWC) is the best means of the present improvement vehicle exhaust that extensively adopts in the world, and the automobile blowdown is reduced more than 90%, satisfies the strict demand of current law basically.But because the main active matter of TWC is Pt, Pd and Rh, the load total amount is about 1.77～4.95g/L.The not only expensive price of this metalloid, and storage on earth is also very limited, can not satisfy the needs of whole world purifying vehicle exhaust at all.In addition, the in short supply of petroleum resources is well-known, is that the vehicle fuel use amount of power source is occupied very big ratio simultaneously with the internal combustion engine in oil product, and this impels people to go to improve the efficient of oil inflame.So novel lean-burn gasoline engine is released in the end of the eighties U.S., day, Europe, air-fuel ratio reaches more than 20, and rate of economizing gasoline is 15%～20%, and this is beyond doubt to a great revolution of auto industry.
The lean-burn gasoline engine moves (the oxygen enrichment lean-burn refers to air-fuel ratio greater than 14.7) under the oxygen enrichment lean burn conditions, this development has not only caused [the O of tail gas outlet
2] higher noble metal or the rare earth oxide catalyst of making be to NO
XReduction or decomposition reaction were lost efficacy, even caused more NO
XGenerate, under this condition, continue to use three-way catalyst will inevitably cause NO
XConversion ratio low, do not meet now to NO
XConcern and control requirement.Lack effective catalyst and become the key factor that hinders the lean-combustion engine marketization.
Summary of the invention
The purpose of this invention is to provide a kind of Catalysts and its preparation method that vehicle exhaust is handled that is used for, the present invention is the catalyst of the processing vehicle exhaust that is suitable under lean burn conditions, this catalyst is to utilizing the HC that exists in the vehicle exhaust, the reaction of CO selective reduction NOx has very high catalytic activity, and also is cleaned simultaneously as the HC and the CO of polluter.
The present invention be with original position synthesis of molecular sieve on the cordierite carrier as complex carrier, carried metal Cu, Ag or Cu-La active component are made; Described molecular sieve is ZSM5 molecular sieve or TS-1 molecular sieve.The percentage that described active component load capacity accounts for catalyst quality is: Cu 0.01%～2%, and La or Ag are respectively 0.01%-2%.Described molecular sieve accounts for 0.01%～1% of catalyst quality.
The Preparation of catalysts method that is used for the vehicle exhaust processing comprises the steps: 1) at reactor Ludox, template agent and water are mixed, add butyl titanate after stirring, described template agent is tetraethyl oxyammonia and tetrabutylammonium hydroxide amine blends.Stirring reaction 6～7 hours places resulting clear liquid with cordierite, in 150～240 ℃ of following static crystallizations 12～90 hours, is washed to neutrality; 2) 130 ℃ of oven dry down were warming up to 550 ℃ of constant temperature calcinings 4 hours then, removed the template agent; 3) Ag of usefulness 0.1mol/l
+Or Cu
2+-La
3+Exchange 16 hours, obtain Ag-TS-1/ cordierite or Cu, the La-TS-1/ cordierite; The mole proportioning of described reactant: 30SiO
2: TiO
2: 3RN: 600H
2O, RN are the template agent.
Preparation method of the present invention can be with Ludox, NaOH, and aluminum sulfate mixes with water; Stirred 2 hours, clear liquid and cordierite were together put in the autoclave 150～240 ℃ of following static crystallizations 12～90 hours, take out sample, distilled water flushing is to neutral, and 130 ℃ of oven dry slowly were warming up to 550 ℃ of constant temperature calcinings 4 hours then; Cu with 0.1mol/l
2+Exchange obtains the Cu-ZSM5/ cordierite; The mole proportioning of described reactant: 1Al
2O
3: 84SiO
2: 10Na
2O: 3500H
2O.
The present invention is used for the processing of vehicle exhaust, under experimental condition, and air speed 10,000～30,000h
-1, temperature is 250～600 ℃, air-fuel ratio 14.7～22 o'clock, the NOx in the purifying automobile tail gas, HC and CO.
The present invention utilizes the HC that discharges in the gasoline combustion, CO, additionally do not adding under the situation of any material, NOx is carried out selective reduction, the NOx conversion ratio is influenced not quite by air-fuel ratio, therefore this catalyst not only can be applicable to common system and also is applicable to the lean-burn system, promptly is applicable to excess oxygen, for example the exhaust aftertreatment system of diesel engine, lean burn gasoline engine.Working as bench test condition air speed 25,000h
-1, when temperature was 405 ℃, the NOx conversion ratio was 63.9%; When air speed is 11,000h
-1The time, the NOx conversion ratio can reach 55.6%.
It is the traditional catalyst life-span weak point of main active component with Cu that the present invention has overcome, and easily the shortcoming of poisoning has realized high stability, and the long-life, good anti-middle toxicity is for practical application provides necessary condition.
Preparation process of the present invention is simple, and is with low cost, and it is active high to be used for the purifying vehicle exhaust catalytic reaction, can purify simultaneously NOx, HC and CO in the vehicle exhaust, is specially adapted to the vent gas treatment of gasoline engine, and application prospect is very wide.The present invention also can be applied to other industrial waste gas purifying and sewage purification.
Description of drawings
Fig. 1 be Cu-ZSM5/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
Fig. 2 is Cu, and La-TS-1/ cordierite catalyst is to NOx, HC, and the CO conversion ratio varies with temperature curve map.
Fig. 3 be Cu-TS-1/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
Fig. 4 be Ag-TS-1/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
The specific embodiment
Example 1 Me-TS-1/ cordierite synthetic (Me: one or both metals):
As the silicon source, as the titanium source, the solution that mixes with certain proportion with tetraethyl oxyammonia and tetrabutylammonium hydroxide amine is the template agent with butyl titanate with Ludox.Ludox, template agent and water are mixed according to a certain percentage, and the back that stirs adds butyl titanate.The proportioning of reactant is as follows: 30SiO
2: TiO
2: 3RN: 600H
2(RN: the template agent) reactant was together put in the autoclave 180 ℃ of following static crystallizations 90 hours with clear liquid and cordierite to O after fast stirring 6 hours.Take out sample, distilled water flushing is to neutral, and 150 ℃ of oven dry slowly were warming up to 550 ℃ of constant temperature calcinings 4 hours then, removed the template agent.Adopt ion-exchange, with the AgNO of 0.1mol/l
3Exchange obtains the Ag-TS-1/ cordierite; If Cu (Ac) with 0.1mol/l
2Exchange obtains the Cu-TS-1/ cordierite.Dry, use the La (NO of 0.1mol/l again
3)
3Exchange obtains Cu, the La-TS-1/ cordierite, and be 16 hours each swap time.
Synthesizing of example 2 Cu-ZSM5/ cordierites:
As the silicon source, aluminum sulfate is the aluminium source with Ludox, need not the template agent.With Ludox, NaOH, aluminum sulfate, water mixes according to a certain percentage.The concrete proportioning of reactant is as follows: 1Al
2O
3: 84SiO
2: 10Na
2O: 3500H
2O.Vigorous stirring 2 hours was together put in the autoclave 180 ℃ of following static crystallizations 16 hours with clear liquid and cordierite, took out sample, and distilled water flushing is to neutral, and 150 ℃ of oven dry slowly were warming up to 550 ℃ of constant temperature calcinings 4 hours then, with the Cu (Ac) of 0.1mol/l
2Exchange obtains the Cu-ZSM5/ cordierite.
Under example 3 lean burn conditions to the purification of vehicle exhaust:
Carry out the catalytic activity test with example 2 prepared catalyst.Test is carried out on four cylinders, 16 valve gasoline engine experimental stands.Load: 21Nm; Rotating speed 1800r/min; Air-fuel ratio 21; Porch NOx concentration: 330ppm; HC concentration 90ppm; CO concentration: 0.18%; Air speed 25000h
-1Experimental result sees Table 1 and Fig. 1.Table 1 be Cu-ZSM5/ cordierite catalyst to NOx, HC, CO concentration and conversion ratio vary with temperature table; Fig. 1 be Cu-ZSM5/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
Table 1 Cu-ZSM5/ cordierite catalyst is to NOx, HC, and CO concentration and conversion ratio vary with temperature table
| Temperature (℃) | NO(ppm) | HC(ppm) | CO (％) | NO conversion ratio (%) | HC conversion ratio (%) | CO conversion ratio (%) |
| 130 | 280 | 86 | 0.16 | 15.1 | 4.4 | 11.1 |
| 170 | 270 | 81 | 0.16 | 18.2 | 10.0 | 11.1 |
| 210 | 254 | 77 | 0.16 | 22.8 | 14.4 | 11.1 |
| 268 | 242 | 73 | 0.17 | 26.7 | 18.9 | 5.6 |
| 310 | 231 | 64 | 0.17 | 30.0 | 28.9 | 5.6 |
| 341 | 206 | 60 | 0.17 | 37.6 | 33.3 | 5.6 |
| 378 | 159 | 44 | 0.17 | 51.8 | 51.1 | 5.6 |
| 405 | 119 | 35 | 0.16 | 63.9 | 61.1 | 11.1 |
| 441 | 124 | 26 | 0.14 | 62.4 | 71.1 | 22.2 |
| 465 | 162 | 24 | 0.13 | 50.9 | 73.3 | 27.8 |
| 493 | 193 | 19 | 0.13 | 41.5 | 78.9 | 27.8 |
| 525 | 230 | 15 | 0.11 | 30.3 | 83.3 | 38.9 |
| 550 | 259 | 1 | 0.05 | 21.5 | 98.9 | 72.2 |
Example 4: comparative example 3, under the lean burn conditions to the purification of vehicle exhaust:
(1) with the prepared Catalysts Cu of example 1, the La-TS-1/ cordierite carries out the catalytic activity test.Test is carried out on four cylinders, 16 valve gasoline engine experimental stands.Load: 21Nm; Rotating speed 1800r/min; Air-fuel ratio 21; Porch NOx concentration: 540ppm; HC concentration 145ppm; CO concentration: 0.11%; Air speed 11000h
-1Experimental result sees Table 2 and Fig. 2.Table 2 is Cu, and La-TS-1/ cordierite catalyst is to NOx, HC, and CO concentration and conversion ratio vary with temperature table; Fig. 2 is Cu, and La-TS-1/ cordierite catalyst is to NOx, HC, and the CO conversion ratio varies with temperature curve map.
Table 2 Cu, La-TS-1/ cordierite catalyst be to NOx, HC, and CO concentration and conversion ratio vary with temperature table
| Temperature (℃) | NO(ppm) | HC(ppm) | CO (％) | NO conversion ratio (%) | HC conversion ratio (%) | CO conversion ratio (%) |
| 242 | 400 | 133 | 0.10 | 26.0 | 9.5 | 16.7 |
| 260 | 402 | 127 | 0.10 | 25.6 | 13.6 | 16.7 |
| 290 | 397 | 117 | 0.10 | 26.4 | 20.4 | 16.7 |
| 310 | 380 | 106 | 0.10 | 30.0 | 27.9 | 16.7 |
| 320 | 355 | 104 | 0.10 | 34.3 | 29.3 | 16.7 |
| 340 | 281 | 86 | 0.11 | 48.0 | 41.5 | 8.3 |
| 350 | 261 | 77 | 0.11 | 51.7 | 47.6 | 8.3 |
| 370 | 240 | 61 | 0.09 | 55.6 | 58.5 | 25.0 |
| 390 | 267 | 51 | 0.07 | 50.6 | 65.3 | 41.7 |
| 410 | 310 | 48 | 0.06 | 42.6 | 67.3 | 50.0 |
| 440 | 375 | 28 | 0.05 | 30.6 | 81.0 | 58.3 |
| 460 | 387 | 24 | 0.03 | 28.3 | 83.7 | 75.0 |
| 480 | 390 | 16 | 0.01 | 27.8 | 89.1 | 91.7 |
| 492 | 390 | 14 | 0 | 27.8 | 90.5 | 100.0 |
| 530 | 405 | 3 | 0 | 25.0 | 98.8 | 100.0 |
| 540 | 410 | 0 | 0 | 24.1 | 100.0 | 100.0 |
| 560 | 433 | 0 | 0 | 19.8 | 100.0 | 100.0 |
(2) carry out the catalytic activity test with example 1 prepared Catalysts Cu-TS-1/ cordierite.Test is carried out on four cylinders, 16 valve gasoline engine experimental stands.Load: 24Nm; Rotating speed 1800r/min; Air-fuel ratio 18.5; Porch NOx concentration: 575ppm; HC concentration 136ppm; CO concentration: 0.34%.Air speed 25000h
-1See Fig. 3.Fig. 3 be Cu-TS-1/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
(3) carry out the catalytic activity test with example 1 prepared catalyst A g-TS-1/ cordierite.Test is carried out on four cylinders, 16 valve gasoline engine experimental stands.Load: 24Nm; Rotating speed 1800r/min; Air-fuel ratio 18; Porch NOx concentration: 575ppm; HC concentration 135ppm; CO concentration: 0.42%.Air speed 25000h
-1See Fig. 4.Fig. 4 be Ag-TS-1/ cordierite catalyst to NOx, HC, the CO conversion ratio varies with temperature curve map.
Claims (7)
1, a kind ofly be used for the catalyst that vehicle exhaust is handled, it is characterized in that it be with original position synthesis of molecular sieve on the cordierite carrier as complex carrier, carried metal Cu, Cu-La or Ag active component are made; Described molecular sieve is ZSM5 molecular sieve or TS-1 molecular sieve.
2, according to claim 1ly be used for the catalyst that vehicle exhaust is handled, it is characterized in that the percentage that described active component load capacity accounts for catalyst quality is: Cu 0.01%～2%, and La or Ag are respectively 0.01%-2%.
3, the catalyst that is used for the vehicle exhaust processing according to claim 1 is characterized in that described molecular sieve accounts for 0.01%～1% of catalyst quality.
4, the described Preparation of catalysts method that is used for the vehicle exhaust processing of claim 1 is characterized in that comprising the steps:
1) in reactor, Ludox, template agent and water are mixed, back adding butyl titanate stirs, described template agent is tetraethyl oxyammonia and tetrabutylammonium hydroxide amine blends, stirring reaction 6～7 hours, cordierite is placed resulting clear liquid, in 150～240 ℃ of following static crystallizations 12～90 hours, be washed to neutrality;
2) 130 ℃ of oven dry down were warming up to 550 ℃ of constant temperature calcinings 4 hours then, removed the template agent;
3) Ag of usefulness 0.1mol/l
+Or Cu
2+-La
3+Exchange 16 hours, obtain Ag-TS-1/ cordierite or Cu, the La-TS-1/ cordierite; Perhaps
With Ludox, NaOH, aluminum sulfate mixes with water; Stirred 2 hours, clear liquid and cordierite were together put in the autoclave 150～240 ℃ of following static crystallizations 12～90 hours, take out sample, distilled water flushing is to neutral, and 130 ℃ of oven dry slowly were warming up to 550 ℃ of constant temperature calcinings 4 hours then; Cu with 0.1mol/l
2+Exchange obtains the Cu-ZSM5/ cordierite.
5, according to claim 4ly be used for the Preparation of catalysts method that vehicle exhaust is handled, it is characterized in that the mole proportioning of described Ludox, template agent and water mixed reactant: 30SiO
2: TiO
2: 3RN: 600H
2O, RN are the template agent.
6, the Preparation of catalysts method that is used for the vehicle exhaust processing according to claim 4 is characterized in that described Ludox, NaOH, the mole proportioning of aluminum sulfate and water mixed reactant: 1Al
2O
3: 84SiO
2: 10Na
2O: 3500H
2O.
7, the described catalyst of claim 1 is used for the processing of vehicle exhaust, under experimental condition, and air speed 10,000～30,000h
-1, temperature is 250～600 ℃, air-fuel ratio 14.7～22 o'clock, the NOx in the purifying automobile tail gas, HC and CO.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031209939A CN1189245C (en) | 2003-03-27 | 2003-03-27 | Catalyst for car tail gas treatment and preparation thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031209939A CN1189245C (en) | 2003-03-27 | 2003-03-27 | Catalyst for car tail gas treatment and preparation thereof |
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| Publication Number | Publication Date |
|---|---|
| CN1439457A CN1439457A (en) | 2003-09-03 |
| CN1189245C true CN1189245C (en) | 2005-02-16 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012007914A3 (en) * | 2010-07-15 | 2012-03-08 | Basf Se | Copper containing zsm-34, off and /or eri zeolitic material for selective reduction of nox |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL1026207C2 (en) * | 2004-05-17 | 2005-11-21 | Stichting Energie | Process for the decomposition of N2O, catalyst for it and preparation of this catalyst. |
| CN101574664B (en) * | 2008-05-09 | 2011-11-09 | 北京化工大学 | Method for synthesizing zeolite on cordierite carrier |
| US9289756B2 (en) | 2010-07-15 | 2016-03-22 | Basf Se | Copper containing ZSM-34, OFF and/or ERI zeolitic material for selective reduction of NOx |
| CN102366723A (en) * | 2011-10-10 | 2012-03-07 | 浙江师范大学 | Precious metal monolithic catalyst for organic waste gas treatment and manufacturing method thereof |
| JP6370713B2 (en) * | 2012-02-06 | 2018-08-08 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method and apparatus for treating a gas stream containing nitrogen oxides |
| CN104415792B (en) * | 2013-08-22 | 2016-08-17 | 中国石油化工股份有限公司 | Cordierite of superficial growth titanium silicon oxide and preparation method thereof |
| CN108554444B (en) * | 2018-05-08 | 2019-07-30 | 哈尔滨工业大学 | A kind of preparation method of multi-stage porous Ti-ZSM-5 molecular sieve auto-exhaust catalyst |
| CN113072815B (en) * | 2021-03-18 | 2022-10-18 | 山西黄河前沿新材料研究院有限公司 | Warm-mixed modified asphalt overlay material capable of adsorbing and degrading tail gas and preparation method thereof |
| CN114887649A (en) * | 2022-07-14 | 2022-08-12 | 中国汽车技术研究中心有限公司 | Coating-free integral type exhaust gas purification catalyst and preparation method thereof |
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2003
- 2003-03-27 CN CNB031209939A patent/CN1189245C/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012007914A3 (en) * | 2010-07-15 | 2012-03-08 | Basf Se | Copper containing zsm-34, off and /or eri zeolitic material for selective reduction of nox |
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|---|---|
| CN1439457A (en) | 2003-09-03 |
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