CN103406141B - Ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts - Google Patents

Ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts Download PDF

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CN103406141B
CN103406141B CN201310301644.XA CN201310301644A CN103406141B CN 103406141 B CN103406141 B CN 103406141B CN 201310301644 A CN201310301644 A CN 201310301644A CN 103406141 B CN103406141 B CN 103406141B
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宋崇林
吕刚
宋金瓯
宾峰
张清茂
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Tianjin University
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Abstract

The invention discloses a kind of ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts.Catalyst adopts copper, cerium, zirconium ternary metal modified molecular screen to be active component, γ-Al 2o 3for coating matrix, cordierite honeycomb ceramic is supported catalyst agent carrier, and cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 10.9 ~ 23.7%/89.1 ~ 76.3%.Preparation technology comprises: the determination of catalyst raw material dosage; The preparation of active component; The preparation of coating paste and load.Catalyst adopts urea or ammonia to be reducing agent, removes the NOx in lean-combustion engine exhaust by SCR.Cerium oxide can improve the low-temperature catalytic activity of catalyst, and zirconia is by forming with cerium oxide the thermal ageing resistant performance that solid solution improves cerium oxide.And there is no toxic material in catalyst, avoid V 2o 5class catalyst is to the harm of health.

Description

Ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts
Technical field
The invention belongs to engine NOx cleaning catalyst, be specifically related to a kind of Catalysts and its preparation method by selective catalytic reduction reaction purification lean-combustion engine nitrogen oxide in tail gas.
Background technology
Automotive emission is NO_x in Air Environment (NO x) one of main source, and NOx is not only detrimental to health, and it is also the precursor of acid rain and photochemical fog, can change into the larger material of harm in the environment, therefore the NOx emission of the Abgasgesetz limiting vehicle of increasingly stringent has all been promulgated in countries in the world.For this reason, engine production business develops multiple NOx purification techniques, the wherein technology extensive use on petrol engine such as triple effect catalytic converter.But containing a certain amount of oxygen in the lean-combustion engine exhausts such as the direct spray petrol engine in cylinder (GDI) of diesel engine and the work of employing lean-burn mode, cause the exhaust gas aftertreatment techniques such as three-effect catalysis to apply.For this reason, SCR (the Selective Catalytic Reduction-SCR) technology that to develop with ammonia or urea be specially reducing agent, the NOx emission for lean-combustion engine controls.
The SCR catalyst having dropped into commercial applications mostly at present is V 2o 5-WO 3(or MoO 3)-TiO 2-ceramic monolith class loaded catalyst, when delivery temperature is in 280 ~ 450 DEG C, this type of catalyst has good NOx clean-up effect.But for congestion in road, the operating condition such as start-stop is frequent, the speed of a motor vehicle is lower, make the delivery temperature of the lean-combustion engines such as bus for a long time lower than 250 DEG C, in the case, catalytic component based on vanadium is difficult to directly apply to above-mentioned operating condition.In addition, V 2o 5belong to highly toxic substance, larger to human health damage.Therefore adopt low toxicity developing material to have the SCR catalyst of good low temperature purifying property, become the study hotspot of Urban Air Pollution Control technical field.The ZSM-5 molecular sieve type catalyst of copper modification has good SCR catalytic performance, but its low temperature active can not meet urban area lean-combustion engine automobile to the requirement of SCR catalyst low temperature active.On the other hand, cerium oxide is a kind of hydrogen-storing material efficiently, and the effect of it and molecular sieve surface and hole internal copper catalytic center effectively can reduce the activation energy that SCR reacts, thus improves the cryogenic property of catalyst.But cerium oxide can lose oxygen storage capacity gradually under long-time high temperature action, and in the solid solution formed at zirconia and cerium oxide, the thermal ageing resistant performance of cerium oxide significantly improves.
The present invention is exactly the SCR catalyst with pole hypotoxicity and good low temperature catalytic performance proposed for the problems referred to above defect.
Summary of the invention
The object of the invention is, a kind of ternary metal remodeling ZSM-5 molecular sieve type, lean-combustion engine selective catalyst reduction of nitrogen oxides Catalysts and its preparation method are provided, exchanged and load on H/ZSM-5 molecular sieve by copper, cerium, zirconium 3 three metal ion species simultaneously, while raising catalyst low-temperature activity, reduce the harm to environmental and human health impacts in catalyst application process.
Technical scheme of the present invention is as follows: ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts, includes copper, cerium, the ZSM-5 molecular sieve of zirconium ion modification, γ-Al 2o 3and cordierite honeycomb ceramic carrier etc.The technical scheme of its catalyst composition is: with copper, cerium, zirconium ternary metal modified molecular screen for active component, and copper, cerium, zirconium three kinds of metallic elements are present in molecular sieve with cupric oxide, cerium oxide, zirconic form respectively.Wherein the molal quantity of cerium oxide with the ratio of zirconic molal quantity is: 30 ~ 70%/70 ~ 30%, and molar percentage sum is 100%; Cerium oxide and zirconic molal quantity summation with the ratio of the molal quantity of cupric oxide are: 1:1.It is that silicon/aluminium atomic quantity is than the ZSM-5 molecular sieve for 25:1 that selective catalytic reduction catalysts prepares adopted molecular sieve, and cupric oxide, cerium oxide, zirconia quality gross weight and ZSM-5 molecular sieve mass ratio are: 10.9 ~ 23.7%/89.1 ~ 76.3%, mass percent sum is 100%.
With γ-Al 2o 3for coating material, and copper, cerium, zirconium ternary metal modified molecular screen active component and γ-Al in coating 2o 3mass percent be: 20 ~ 40%/80 ~ 60%, mass percent sum is 100%.
γ-Al in described coating 2o 3respectively from pure matter γ-Al 2o 3with the γ-Al generated after boehmite calcining 2o 3, and from pure matter γ-Al 2o 3with the γ-Al from generation after boehmite calcining 2o 3mass percent be: 50 ~ 70%/50 ~ 30%, mass percent sum is 100%.
With 400 object cordierite honeycomb ceramics for supported catalyst agent carrier, and copper, cerium, zirconium ternary metal modified molecular screen and γ-Al 2o 3the coating gross weight of common composition and the mass percent of 400 order cordierite honeycomb ceramic carriers are: 10 ~ 20%/90 ~ 80%, and mass percent sum is 100%.
The preparation method of ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts, its concrete preparation technology comprises following four steps:
(1) determination of Kaolinite Preparation of Catalyst raw material dosage
With aforementioned each proportioning, calculate cupric oxide in catalyst, cerium oxide, zirconia, ZSM-5 molecular sieve, pure matter γ-Al respectively 2o 3γ-Al is generated after powder and boehmite calcining 2o 3mass ratio.
Respectively according to every 199.65g copper acetate [Cu (CH 3cOO) 2h 2o] produce 79.55g cupric oxide; Every 434.12g cerous nitrate [Ce (NO 3) 36H 2o] produce 172.11g cerium oxide; Every 429.32g zirconium nitrate [Zr (NO 3) 45H 2o] produce the zirconic ratio of 123.22g, converse the quality of needed raw material copper acetate, cerous nitrate and zirconium nitrate.In addition, the quality of boehmite needed for Kaolinite Preparation of Catalyst is calculated according to the alumina content that boehmite packaging bag marks.
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by fixed quality, and three kinds of dissolving metal salts are become mixed solution by the ratio adding 20 ~ 50ml deionized water according to every 1g slaine; To determine that the ZSM-5 molecular sieve of quality adds in this mixed solution, and at 70 ~ 80 DEG C high degree of agitation 6 ~ 12h, by liquid evaporate to dryness after having stirred.Then at 100 ~ 120 DEG C, the powder after evaporate to dryness is dried 4 ~ 8h, the powder after oven dry is high-temperature roasting 2 ~ 3h at 550 ~ 600 DEG C, can obtain copper, cerium, zirconium ternary metal modified zsm-5 zeolite active component.
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite, need 5 ~ 20g mean molecule quantity to be the polyethylene glycol of 4000 and the ratio of 100g nitric acid according to every 100g ternary metal modified molecular screen powder, take polyethylene glycol and nitric acid.Under vigorous stirring, by the ternary metal modified molecular screen active component prepared, pure matter γ-Al 2o 3powder, boehmite and polyethylene glycol are dispersed in the salpeter solution of dilution 20 times, obtain coating paste, sealed by gained slurry, leave standstill, obtain stable slurry after 72h.
(4) load of coating paste
The quality of 400 order cordierite honeycomb ceramic carriers of load coating as required and the proportion of coating quality and carrier quality, take 400 order cordierite honeycomb ceramic carriers of quality, and be immersed in stable slurry, flood 2 ~ 4 hours at 60 ~ 80 DEG C, after dipping terminates, ceramic monolith is taken out from slurry, blows residual liquid in duct off, dry 4 ~ 8h at 80 ~ 110 DEG C, then 2h is calcined at 550 DEG C.After carrier cooling after load coating, claim its quality, the difference of this quality and cordierite honeycomb ceramic carrier initial mass, be the gross mass of coating.Repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope mapped out, then calcines 2 ~ 3h by the cordierite honeycomb ceramic carrier after load coating at 550 ~ 600 DEG C.
The beneficial effect of feature of the present invention and generation is: catalyst adopts urea or ammonia to be reducing agent, by the NOx in the exhaust of SCR purification lean-combustion engine.In catalyst, Ce elements is outer by improving the low-temperature catalytic activity of catalyst with the effect of copper catalytic center at molecular sieve pore passage with the form of cerium oxide, and zirconium with zirconic form by forming with cerium oxide the thermal ageing resistant performance that solid solution improves cerium oxide, thus significantly improve the low-temperature catalytic activity of metal modified molecular screen type SCR catalyst and the heat endurance of cerium oxide.In addition, the cupric oxide contained in catalyst, cerium oxide, zirconia, ZSM-5 molecular sieve, γ-Al 2o 3and cordierite carrier, be all nontoxic or low toxicity material, avoid V 2o 5class SCR catalyst is to the adverse effect of health.
Accompanying drawing explanation
Fig. 1 is selective catalytic reduction catalysts catalytic activity laboratory evaluation system diagram.
Wherein: 1-single channel mass flow controller; 2-3 channel quality flow controller; 3-spinner flowmeter; 4-stop valve; 5-air flue; 6-mixing kettle; 7-steam producer; 8-reactor; 9-display temperature controller; 10-heating current display and control instrument; 11-peristaltic pump; 12-NH 3gas cylinder; 13-NO gas cylinder; 14-HC gas cylinder; 15-CO gas cylinder; 16-O 2/ N 2gas cylinder (wherein O 2volumetric concentration is 11%); 17-simulated engine gas inlet; 18-NH 3entrance; 19-steam entry; 20-reacts final vacuum outlet (towards gas analyzer).
Fig. 2 is in catalyst activity laboratory evaluation system, demonstrates the situation of change of purification efficiency with reaction temperature of embodiment 1 ~ 4 couple of NO.
Fig. 3 is SCR catalyst catalytic performance engine appraisement system system composition diagram.
Wherein: 21-dynamometer machine; 22-diesel engine; 23-inlet air flow gauge; 24-air inlet air conditioning; 25-NOx sensor; 26-reductant nozzle; 27-exhaust gas temperature sensor; 28-SCR catalyst converter; 29-injection of reducing agent amount of jet control system; 30-reducing agent storage tank; 31-ammonia analyzer; 32-exhaust gas sampling passage; 33-emission analyzer.
Fig. 4, for utilizing engine evaluation system, demonstrates embodiment 1 ~ 4 purification efficiency to NOx when engine exhaust temperature is 220 DEG C.
Fig. 5, for utilizing engine evaluation system, demonstrates embodiment 1 ~ 4 purification efficiency to NOx when engine exhaust temperature is 350 DEG C.
Detailed description of the invention
Below by way of by reference to the accompanying drawings and specific embodiment, technical scheme of the present invention is further described.It should be noted that described embodiment is narrative, but not determinate, the content that the present invention is contained is not limited to following embodiment.
With copper, cerium, zirconium ternary metal modified molecular screen for active component, and copper, cerium, zirconium three kinds of metallic elements are present in molecular sieve with cupric oxide, cerium oxide, zirconic form respectively.Wherein the molal quantity of cerium oxide with the ratio of zirconic molal quantity is: 30 ~ 70%/70 ~ 30%; Cerium oxide and zirconic molal quantity summation with the ratio of the molal quantity of cupric oxide are: 1:1, and molar percentage sum is 100%.It is that silicon/aluminium atomic quantity is than the ZSM-5 molecular sieve for 25:1 that selective catalytic reduction catalysts prepares adopted molecular sieve, and cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 10.9 ~ 23.7%/89.1 ~ 76.3%, mass percent sum is 100%.
With γ-Al 2o 3for coating material, and copper, cerium, zirconium ternary metal modified molecular screen active component and γ-Al in coating 2o 3mass percent be: 20 ~ 40%/80 ~ 60%, mass percent sum is 100%.
γ-Al in described coating 2o 3respectively from pure matter γ-Al 2o 3with the γ-Al generated after boehmite calcining 2o 3, and from pure matter γ-Al 2o 3with the γ-Al from generation after boehmite calcining 2o 3mass percent be: 50 ~ 70%/50 ~ 30%, mass percent sum is 100%.
With 400 object cordierite honeycomb ceramics for supported catalyst agent carrier, and copper, cerium, zirconium ternary metal modified molecular screen and γ-Al 2o 3the coating quality gross weight of common composition and the mass percent of 400 order cordierite honeycomb ceramic carriers are: 10 ~ 20%/90 ~ 80%, and mass percent sum is 100%.
Embodiment 1
(1) determination of Kaolinite Preparation of Catalyst raw material dosage
Design needs the molal quantity of cerium oxide in Kaolinite Preparation of Catalyst with the ratio of zirconic molal quantity to be: 30%:70%; Cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 10.9%:89.1%; Active component and coating matrix γ-Al 2o 3mass ratio be: 40%:60%; Pure matter γ-Al 2o 3powder and the rear γ-Al generated of boehmite calcining 2o 3mass ratio be: 50%:50%.Determine that the coating gross mass of planning preparation is 50000g, calculate total cupric oxide 796g, cerium oxide 516g, zirconia 862g, ZSM-5 molecular sieve 17826g, pure matter γ-Al in coating thus 2o 3γ-Al is generated after the calcining of powder 15000g, boehmite 2o 3quality 15000g.Can calculate according to conversion scale and prepare coating paste and need copper acetate 1997g, cerous nitrate 1302g, zirconium nitrate 3005g.Al in the boehmite that the present embodiment uses 2o 3content be 71%, can calculate thus needs boehmite 21127g.
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by fixed quality, three kinds of slaines are dissolved in 126.1L deionized water jointly, stir until slaine dissolves completely, form mixed solution.To determine that the ZSM-5 molecular sieve of quality adds in this mixed salt solution, at 80 DEG C after high degree of agitation 6h by liquid evaporate to dryness.Then at 100 DEG C, the powder after evaporate to dryness is dried 8h, then by the powder high-temperature roasting 3h at 550 DEG C after oven dry, copper, cerium, zirconium ternary metal modified molecular screen powder can be obtained.
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite.Under high degree of agitation, by the ternary metal modified molecular screen powder prepared, the pure matter γ-Al taken 2o 3powder and boehmite and 2000g mean molecule quantity be 4000 polyethylene glycol be dispersed in the 20000g nitric acid of dilution 20 times, obtain coating paste.Gained slurry is sealed, leaves standstill, after 72h, obtain stable slurry.
(4) load of coating paste
Taking the cylindrical 400 order cordierite honeycomb ceramic carriers (volume is about 5.76L) of 2880g is immersed in stable slurry, floods 4 hours at 60 DEG C.After dipping terminates, ceramic monolith is taken out from slurries, blows residual liquid in duct off, dry 6h at 100 DEG C, then calcine 2h at 550 DEG C.Weigh after carrier cooling after load coating, and calculate coating quality.Repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope of pre-determined 18 ~ 20%, then calcines 3h by the cordierite honeycomb ceramic carrier after load coating at 550 DEG C.Carrier after load coating and coating thereof are generically and collectively referred to as loaded catalyst.Through weighing and calculating, the loaded catalyst floating coat quality of the present embodiment accounts for 18.8% of loaded catalyst gross mass.
Embodiment 2
(1) determination of Kaolinite Preparation of Catalyst raw material dosage
Design needs the molal quantity of cerium oxide in Kaolinite Preparation of Catalyst with the ratio of zirconic molal quantity to be: 70%:30%; Cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 23.7%:76.3%; Active component and coating matrix γ-Al 2o 3mass ratio be: 20%:80%; Pure matter γ-Al 2o 3powder and the rear γ-Al generated of boehmite calcining 2o 3mass ratio be: 50%:50%.Determine that the coating gross mass of planning preparation is 50000g, calculate total cupric oxide 796g, cerium oxide 1205g, zirconia 370g, ZSM-5 molecular sieve 7629g, pure matter γ-Al in coating thus 2o 3γ-Al is generated after the calcining of powder 20000g, boehmite 2o 3quality 20000g.Can calculate according to conversion scale and prepare coating paste and need copper acetate 1997g, cerous nitrate 3039g, zirconium nitrate 1288g.Al in the boehmite that the present embodiment uses 2o 3content be 71%, can calculate thus needs boehmite 28169g.
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by described fixed quality, described 3 kinds of slaines are dissolved in 316.2L deionized water jointly, stir until slaine dissolves completely, form mixed solution.Determined that the ZSM-5 molecular sieve of quality adds in described mixed salt solution by described, at 70 DEG C after high degree of agitation 12h by liquid evaporate to dryness.Then at 120 DEG C, the powder after described evaporate to dryness is dried 4h, then by the high-temperature roasting 3h at 550 DEG C of the powder after described oven dry, copper, cerium, zirconium ternary metal modified molecular screen powder can be obtained.
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite.Under high degree of agitation, by the ternary metal modified molecular screen powder prepared, the pure matter γ-Al taken 2o 3powder and boehmite and 2000g mean molecule quantity be 4000 polyethylene glycol be dispersed in the 10000g nitric acid of dilution 20 times, obtain coating paste.Gained slurry is sealed, leaves standstill, after 72h, obtain stable slurry.
(4) load of coating paste
Taking the cylindrical 400 order cordierite honeycomb ceramic carriers (volume is about 5.76L) of 2880g is immersed in stable slurry, floods 2 hours at 80 DEG C.After dipping terminates, ceramic monolith is taken out from slurries, blows residual liquid in duct off, dry 4h at 110 DEG C, then calcine 2h at 550 DEG C.Weigh after carrier cooling after load coating, and calculate coating quality.Repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope of pre-determined 18 ~ 20%, then calcines 3h by the cordierite honeycomb ceramic carrier after load coating at 550 DEG C.Carrier after load coating and coating thereof are generically and collectively referred to as loaded catalyst.Through weighing and calculating, the loaded catalyst floating coat quality of the present embodiment accounts for 18.2% of loaded catalyst gross mass.
Embodiment 3
(1) determination of Kaolinite Preparation of Catalyst raw material dosage
Design needs the molal quantity of cerium oxide in Kaolinite Preparation of Catalyst with the ratio of zirconic molal quantity to be: 30%:70%; Cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 21.7%:78.3%; Active component and coating matrix γ-Al 2o 3mass ratio be: 20%:80%; Pure matter γ-Al 2o 3powder and the rear γ-Al generated of boehmite calcining 2o 3mass ratio be: 70%:30%.Determine that the coating gross mass of planning preparation is 50000g, calculate total cupric oxide 796g, cerium oxide 516g, zirconia 863g, ZSM-5 molecular sieve 7825g, pure matter γ-Al in coating thus 2o 3γ-Al is generated after the calcining of powder 28000g, boehmite 2o 3quality 12000g.Can calculate according to conversion scale and prepare coating paste and need copper acetate 1997g, cerous nitrate 1302g, zirconium nitrate 3005g.Al in the boehmite that the present embodiment uses 2o 3content be 71%, can calculate thus needs boehmite 16901g.
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by fixed quality, three kinds of slaines are dissolved in 252L deionized water jointly, stir until slaine dissolves completely, form mixed solution.To determine that the ZSM-5 molecular sieve of quality adds in mixed salt solution, at 80 DEG C after high degree of agitation 6h by liquid evaporate to dryness.Then at 120 DEG C, the powder after evaporate to dryness is dried 4h, then by the powder high-temperature roasting 2h at 600 DEG C after oven dry, copper, cerium, zirconium ternary metal modified molecular screen powder can be obtained.
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite.Under high degree of agitation, by the ternary metal modified molecular screen powder prepared, the pure matter γ-Al taken 2o 3powder and boehmite and 2000g mean molecule quantity be 4000 polyethylene glycol be dispersed in the 10000g nitric acid of dilution 20 times, obtain coating paste.Gained slurry is sealed, leaves standstill, after 72h, obtain stable slurry.
(4) load of coating paste
Taking the cylindrical 400 order cordierite honeycomb ceramic carriers (volume is about 5.76L) of 2880g is immersed in stable slurry, floods 3 hours at 70 DEG C.After dipping terminates, ceramic monolith is taken out from slurries, blows residual liquid in duct off, dry 6h at 100 DEG C, then calcine 2h at 550 DEG C.Weigh after carrier cooling after load coating, and calculate coating quality.Repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope of pre-determined 14 ~ 16%, then calcines 3h by the cordierite honeycomb ceramic carrier after load coating at 550 DEG C.Carrier after load coating and coating thereof are generically and collectively referred to as loaded catalyst.Through weighing and calculating, the loaded catalyst floating coat quality of the present embodiment accounts for 14.7% of loaded catalyst gross mass.
Embodiment 4
(1) determination of Kaolinite Preparation of Catalyst primary raw material consumption
Design needs the molal quantity of cerium oxide in Kaolinite Preparation of Catalyst with the ratio of zirconic molal quantity to be: 50%:50%; Cupric oxide, cerium oxide, zirconia quality summation and ZSM-5 molecular sieve mass ratio are: 22.7%:77.3%; Active component and coating matrix γ-Al 2o 3mass ratio be: 30%:70%; Pure matter γ-Al 2o 3powder and the rear γ-Al generated of boehmite calcining 2o 3mass ratio be: 50%:50%.; Determine that the coating gross mass of planning preparation is 50000g, and calculate total cupric oxide 1193g, cerium oxide 1291g, zirconia 924g, ZSM-5 molecular sieve 11592g, pure matter γ-Al in coating thus 2o 3γ-Al is generated after the calcining of powder 17500g, boehmite 2o 3quality 17500g.Can calculate according to conversion scale and prepare coating paste and need copper acetate 2995g, cerous nitrate 3256g, zirconium nitrate 3220g.Al in the boehmite that the present embodiment uses 2o 3content be 71%, can calculate thus needs boehmite 24648g.
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by fixed quality, three kinds of slaines are dissolved in 189.4L deionized water jointly, stir until slaine dissolves completely, form mixed solution.To determine that the ZSM-5 molecular sieve of quality adds in this mixed salt solution, at 80 DEG C after high degree of agitation 6h by liquid evaporate to dryness.Then at 120 DEG C, the powder after evaporate to dryness is dried 4h, then by the powder high-temperature roasting 2h at 600 DEG C after oven dry, copper, cerium, zirconium ternary metal modified molecular screen powder can be obtained.
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite.Under high degree of agitation, by the ternary metal modified molecular screen powder prepared, the pure matter γ-Al taken 2o 3powder and boehmite and 750g mean molecule quantity be 4000 polyethylene glycol be dispersed in the 15000g nitric acid of dilution 20 times, obtain coating paste.Gained slurry is sealed, leaves standstill, after 72h, obtain stable slurry.
(4) load of coating paste
Taking the cylindrical 400 order cordierite honeycomb ceramic carriers (volume is about 5.76L) of 2880g is immersed in stable slurry, floods 3 hours at 70 DEG C.After dipping terminates, ceramic monolith is taken out from slurry, blows residual liquid in duct off, dry 6h at 100 DEG C, then calcine 2h at 550 DEG C.Repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope of pre-determined 10 ~ 12%, then calcines 2h by the cordierite honeycomb ceramic carrier after load coating at 600 DEG C.Weigh after carrier cooling after load coating, and calculate coating quality.Carrier after load coating and coating thereof are generically and collectively referred to as loaded catalyst.Through weighing and calculating, the loaded catalyst floating coat quality of the present embodiment accounts for 10.7% of loaded catalyst gross mass.
The NO SCR purifying property of the SCR catalyst hot laboratory evaluation system shown in Fig. 1 to above-described embodiment 1-4 is adopted to evaluate.Its test method is: in reactor 8, add loaded catalyst 10mL.Be 9.5L/min, CO by the NO in the CO in the oxygen in steel cylinder 16, nitrogen mixed gas, steel cylinder 15, the propane in steel cylinder 14 and steel cylinder 13 according to oxygen, nitrogen mixed gas by spinner flowmeter 3 and 3 channel quality flow controller 2 be 6.5mL/min, the flow velocity of propane to be 2.5mL/min, NO be 8.0mL/min enters respectively in mixing kettle 6 and mix, then mist enters in reactor 8 again.In adjustment steam producer 7, the growing amount of steam is 500mL/min, and is added in reactor by steam by steam entry 19.And the NH in steel cylinder 12 3gas, under the control of single channel quality controller 1, enters reactor 8 with the flow velocity of 8.0mL/min, and SCR catalytic reaction occurs the gaseous mixture flowed out with mixing kettle 6 catalyst surface in the reactor.The temperature range of reactor is 100-350 DEG C, is controlled by display temperature controller 9.Reacted gaseous mixture enters after discharging from 20 mouthfuls and carries out NO concentration analysis regardless of light infrared analysis system.Result as shown in Figure 2.
The NOx selective catalytic reduction purifying property of SCR catalyst reactive engine evaluation system to above-described embodiment 1-4 shown in Fig. 3 is adopted to evaluate.Experiment adopts CY4102 diesel engine, Siemens's NOx sensor, and reducing agent is the liquefied ammonia directly sprayed, and mole injection flow of liquefied ammonia is 1:1 with the ratio of the molar flow of NOx in SCR catalyst front exhaust.Its test method is: the moment of torsion and the rotating speed that use dynamometer machine 21 Control experiment engine 22, the ratio of adjustment engine exhaust flow and catalyst volume is 60000h -1, and the delivery temperature successively controlling SCR catalyst central point is respectively 220 DEG C and 350 DEG C, carries out catalyst activity measurement.In test, measuring-signal is delivered to injection of reducing agent amount of jet control system 29 by NOx sensor 25 and exhaust gas temperature sensor 27, calculate the injection dosage of reducing agent through single board computer wherein and corresponding software, and by adjustment reductant nozzle 26 dutycycle by the reducing agent liquefied ammonia in storage tank 30 by determining that metering sprays in gas extraction system.NH after vaporization 3gas enters in SCR catalyst 28 after mixing with the exhaust of engine 22 and carries out SCR catalytic reaction.The concentration of the NOx after reaction in gaseous mixture carries out quantitative analysis by emission analyzer 33.Result as shown in Figure 4 and Figure 5.
Need before experiment to carry out encapsulation process to the cylindrical load type catalyst of embodiment 1-4.
Pure matter γ-Al 2o 3powder adopts analyzes pure level γ-Al 2o 3.
Copper, cerium, zirconium ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts adopt urea or ammonia to be reducing agent, by the NOx in the exhaust of selective catalytic reduction reaction purification lean-combustion engine.

Claims (5)

1. ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts, includes copper, cerium, the ZSM-5 molecular sieve of modified zirconia, γ-Al 2o 3and cordierite honeycomb ceramic carrier, it is characterized in that: with copper, cerium, zirconium ternary metal modified molecular screen for active component, and copper, cerium, zirconium three kinds of metallic elements are present in molecular sieve with cupric oxide, cerium oxide, zirconic form respectively, wherein the molal quantity of cerium oxide with the ratio of zirconic molal quantity is: 30 ~ 70%/70 ~ 30%, molar percentage sum is 100%, and cerium oxide and zirconic molal quantity summation with the ratio of the molal quantity of cupric oxide are: 1:1; It is that silicon/aluminium atomic quantity is than the ZSM-5 molecular sieve for 25:1 that selective catalytic reduction catalysts prepares adopted molecular sieve, and cupric oxide, cerium oxide, zirconia quality summation and described ZSM-5 molecular sieve mass ratio are: 10.9 ~ 23.7%/89.1 ~ 76.3%, mass percent sum is 100%.
2., according to ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts according to claim 1, it is characterized in that: with γ-Al 2o 3for coating material, and copper, cerium, zirconium ternary metal modified molecular screen active component and γ-Al in coating 2o 3mass percent be: 20 ~ 40%/80 ~ 60%, mass percent sum is 100%.
3., according to ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts according to claim 2, it is characterized in that: the γ-Al in described coating 2o 3respectively from pure matter γ-Al 2o 3with the γ-Al generated after boehmite calcining 2o 3, and from pure matter γ-Al 2o 3with the γ-Al from generation after boehmite calcining 2o 3mass percent be: 50 ~ 70%/50 ~ 30%, mass percent sum is 100%.
4. according to the ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts described in claim 1 or 2, it is characterized in that: with 400 object cordierite honeycomb ceramics for supported catalyst agent carrier, and described copper, cerium, zirconium ternary metal modified molecular screen and γ-Al 2o 3the coating quality gross weight of common composition and the mass percent of 400 order cordierite honeycomb ceramic carriers are: 10 ~ 20%/90 ~ 80%, and mass percent sum is 100%.
5., according to a preparation method for one of Claims 1-4 described ternary metal modified molecules sieve-type lean-combustion engine selective catalytic reduction catalysts, it is characterized in that concrete preparation technology comprises the following steps:
(1) determination of Kaolinite Preparation of Catalyst raw material dosage
With proportioning each described in claims 1 to 3, calculate cupric oxide in catalyst, cerium oxide, zirconia, ZSM-5 molecular sieve, pure matter γ-Al respectively 2o 3γ-Al is generated after powder and boehmite calcining 2o 3mass ratio,
According to every 199.65g copper acetate [Cu (CH 3cOO) 2h 2o] produce 79.55g cupric oxide; Every 434.12g cerous nitrate [Ce (NO 3) 36H 2o] produce 172.11g cerium oxide; Every 429.32g zirconium nitrate [Zr (NO 3) 45H 2o] produce the zirconic ratio of 123.22g, converse the quality of needed raw material copper acetate, cerous nitrate and zirconium nitrate, in addition, calculate the quality of boehmite needed for Kaolinite Preparation of Catalyst according to the alumina content that boehmite packaging bag marks;
(2) preparation of active component
Take copper acetate, cerous nitrate and zirconium nitrate by fixed quality, and three kinds of dissolving metal salts are become mixed solution by the ratio adding 20 ~ 50ml deionized water according to every 1g slaine; To determine that the ZSM-5 molecular sieve of quality adds in this mixed solution, and at 70 ~ 80 DEG C high degree of agitation 6 ~ 12h, by liquid evaporate to dryness after having stirred; Then at 100 ~ 120 DEG C, the powder after evaporate to dryness is dried 4 ~ 8h, the powder after oven dry is high-temperature roasting 2 ~ 3h at 550 ~ 600 DEG C, can obtain copper, cerium, zirconium ternary metal modified zsm-5 zeolite active component;
(3) preparation of coating paste
Pure matter γ-Al is taken by fixed quality 2o 3powder and boehmite, 5 ~ 20g mean molecule quantity is needed to be the polyethylene glycol of 4000 and the ratio of 100g nitric acid according to every 100g ternary metal modified molecular screen powder, take polyethylene glycol and nitric acid, under vigorous stirring, by the ternary metal modified molecular screen active component prepared, pure matter γ-Al 2o 3powder, boehmite and polyethylene glycol be dispersed in dilution 20 times determine in the nitric acid of quality, obtain coating paste, by gained slurry seal, leave standstill, obtain stable slurry after 72h;
(4) load of coating paste
The quality of 400 order cordierite honeycomb ceramic carriers of load coating as required, and the proportion of coating quality and carrier quality, take 400 order cordierite honeycomb ceramic carriers, and be immersed in stable slurry, flood 2 ~ 4 hours at 60 ~ 80 DEG C, after dipping terminates, ceramic monolith is taken out from slurry, blow residual liquid in duct off, dry 4 ~ 8h at 80 ~ 110 DEG C, 2h is calcined again at 550 DEG C, after carrier cooling after load coating, claim its quality, the difference of this quality and cordierite honeycomb ceramic carrier initial mass, be the gross mass of coating, repeatedly repeated impregnations, drying and calcination process, until the mass percent of coating reaches the mass percent scope mapped out, again the cordierite honeycomb ceramic carrier after load coating is calcined 2 ~ 3h at 550 ~ 600 DEG C.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107930678A (en) * 2017-12-05 2018-04-20 合肥神舟催化净化器股份有限公司 A kind of selective catalytic reduction catalysts and preparation method based on copper vanadium dual metal modified molecular screen

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102489326A (en) * 2011-12-15 2012-06-13 无锡威孚环保催化剂有限公司 Natural gas and tail gas cleaning catalyst and preparation method thereof
CN103008001A (en) * 2011-09-22 2013-04-03 中国石油化工股份有限公司 Fischer-Tropsch synthesis catalyst comprising composite molecular sieve, and preparation method and application thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103008001A (en) * 2011-09-22 2013-04-03 中国石油化工股份有限公司 Fischer-Tropsch synthesis catalyst comprising composite molecular sieve, and preparation method and application thereof
CN102489326A (en) * 2011-12-15 2012-06-13 无锡威孚环保催化剂有限公司 Natural gas and tail gas cleaning catalyst and preparation method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107930678A (en) * 2017-12-05 2018-04-20 合肥神舟催化净化器股份有限公司 A kind of selective catalytic reduction catalysts and preparation method based on copper vanadium dual metal modified molecular screen

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