CN106732552A - A kind of meso-porous alumina loads the preparation method and applications of palladium-based catalyst - Google Patents
A kind of meso-porous alumina loads the preparation method and applications of palladium-based catalyst Download PDFInfo
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- CN106732552A CN106732552A CN201610961978.3A CN201610961978A CN106732552A CN 106732552 A CN106732552 A CN 106732552A CN 201610961978 A CN201610961978 A CN 201610961978A CN 106732552 A CN106732552 A CN 106732552A
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- palladium
- porous alumina
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/44—Palladium
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
- F01N3/28—Construction of catalytic reactors
- F01N3/2803—Construction of catalytic reactors characterised by structure, by material or by manufacturing of catalyst support
- F01N3/2807—Metal other than sintered metal
Abstract
The present invention discloses the preparation method and applications that a kind of meso-porous alumina loads palladium-based catalyst, belongs to catalysis material technical field.The method of the invention is comprised the following steps：First, it is silicon source to intend thin aluminium stone, with surfactant polyethylene (PEG) as template, mesoporous alumina carrier is obtained by drying, high-temperature calcination.Then, with palladium nitrate (Pd (NO3)2) it is active component presoma, loaded on mesoporous alumina carrier using infusion process.Finally, catalyst of the invention is obtained by drying, calcining.The present invention makes full use of the material mesoporous prepared by surfactants' templating to have the features such as high-specific surface area, duct Parameter adjustable control, from the cheap thin aluminium stone of plan, it is significant to catalysis material, environmental technology field by simple dipping, the dry, catalyst that calcining and other processes can obtain high-specific surface area, catalytic active component decentralization is high, catalysis activity is high, ageing resistace is good.
Description
Technical field
A kind of meso-porous alumina of the present invention loads the preparation method and applications of palladium-based catalyst, belongs to catalysis material, ring
Protect technical field.It is widely used in motor-driven Pollution from the engine exhaust control, especially for use combustion gas class (such as methane CH4Deng) motor-driven
Locomotive emissions are better.
Background technology
Natural gas and auto tail gas emission is main with methane (CH4) based on.According to climate change Senior Administrative Officer between supergovernment
Meeting (Intergovernmental Panel on Climate Change, IPCC) second assessment report show, unit volume
CH4The potentiality that heats be carbon dioxide (CO2) 21 times.Therefore, how CH is efficiently eliminated4As place after natural gas and auto tail gas
Manage the subject matter of catalyst.Due to CH4Stable performance is difficult to activate or aoxidize and its temperature needed for catalysis burning is higher, this
Outward, substantial amounts of vapor can be produced in catalyticing combustion process, a small amount of sulphur is also contained in methane gas, therefore, it is methyl hydride catalyzed
Combustion catalyst need to possess active, the higher hydrothermal stability of good low temperature conversion and certain sulfur poisoning resistance.Mesh
Before, CH4Catalyst is mainly noble metal catalyst based on platinum (Pt), palladium (Pd), golden (Au) and with transiting metal oxidation
Metal oxide catalyst based on thing, perofskite type oxide, sharp metal and stone type oxide.With metal oxide catalyst phase
Than, noble metal turns into study hotspot because it possesses good low-temperature oxidation and anti-poisoning capability, wherein, Pd base catalyst
Active highest, most widely used, most researching value.
At present, the research to the Pd base catalyst stabilities for methyl hydride combustion focuses primarily upon two aspects：(1) improve expensive
The decentralization of metal so that crystal grain is the smaller the better (Pd size controllings are in 3nm or so), and noble metal is enriched with carrier surface,
The use potentiality of noble metal are played to greatest extent；Reduce load capacity and cause that the distance between fine particle of noble metal increases, certain
Migration is not easily passed through under reaction condition and big particle is gathered into.But this is a dynamics Delay Process, can only extend metal
The time of sintering can not fundamentally solve the problems, such as stability；(2) using the carrier with special pore structure, by selection
Preparation method makes active metal be supported in duct, so as to prevent the migration of noble metal granule and increase its stability.Therefore, select
Select suitable carrier has important influence to the activity and stability of Pd base catalyst.
So far, aluminum oxide (Al2O3) there is high specific surface area, good heat endurance, special pore structure because of it
And be widely used.Wherein, for the relatively conventional aluminum oxide of meso-porous alumina, with specific surface area higher, pore volume and narrower
Pore-size distribution caused extensive concern.At present, the preparation method of meso-porous alumina mainly have electrochemical process, hydrothermal synthesis method,
Sol-gel process and template.Wherein, electrochemical process preparation technology is more complicated, cost of manufacture is higher and low yield；Hydro-thermal
Synthetic method needs severe reaction conditions, while there is also certain potential safety hazard；Sol-gel process is although can obtain specific area
Meso-porous alumina, but its product pore structure controllability is very poor and expensive raw material price, course of reaction in need it is a large amount of poisonous organic
Reagent；Template synthesis method is simple and product property is superior, therefore, it is the best approach that template prepares meso-porous alumina.Pin
Prepared by method to template, the Chinese invention patent of Patent No. ZL2012121196585 describes a kind of meso-porous alumina support type
The preparation method and application of metallic catalyst；The Chinese invention patent of Patent No. ZL2014107879452 describes one kind to be had
The preparation method of sequence meso-porous alumina copper-loading catalyst.
At present, the catalyst with meso-porous alumina as carrier is primarily present problems with：(1) synthesis of meso-porous alumina with
Alcohol aluminium salt is silicon source, but alcohol aluminium salt easily hydrolyzes in water phase, researcher use in synthetic system addition organic solvent come
Its hydrolysis rate is controlled, and general all poisonous and alcohol aluminium salt the relatively costly, synthesis condition of organic solvent is also very complicated；(2) by
Trivalent metal ion is formed in aluminium element, it is impossible to form the aluminum-oxygen tetrahedron construction unit of stabilization, the meso-porous alumina for synthesizing
Material heat endurance is poor, and pore structure is easily caved in after template is removed.
Summary, with simple, inexpensive, harmless, raisings environmental benefit is starting point to the present invention, it is proposed that a kind of mesoporous oxygen
Change the preparation method of aluminium load palladium-based catalyst and prepared catalyst is applied to CH4Catalyst combustion.
The content of the invention
The deficiency that meso-porous alumina loads Pd base catalyst is prepared in order to make up tradition, the invention provides a kind of mesoporous oxygen
Change the preparation method of aluminium load palladium-based catalyst and prepared catalyst is applied to CH4Catalyst combustion.The present invention fills
Divide the features such as there is high-specific surface area, duct Parameter adjustable control using material mesoporous prepared by surfactants' templating, choosing
With the cheap thin aluminium stone of plan, and by simple dipping, dry, calcining and other processes can obtain high-specific surface area, catalysis is lived
Property component decentralization is high, the catalyst that catalysis activity is high, ageing resistace is good, there is weight to catalysis material, environmental technology field
Want meaning.
It is an object of the invention to provide a kind of meso-porous alumina with ordering rule structure as carrier loaded your gold
Category palladium is used for the preparation method of catalysis oxidation methane, and the method is comprised the following steps：
(1) weigh 10g boehmites (technical grade, percentage of water loss is 15%), to be dissolved in 150mL deionized waters,
Obtain solution A；
(2) dust technology regulation solution PH is added to it after stirring 30min solution As, is adjusted to 3, obtain solution B；
(3) in B solution add 5g polyethylene glycol, stir 180min, under the conditions of 100 DEG C 10-24h of freeze-day with constant temperature,
2-4h of freeze-day with constant temperature under the conditions of 600 DEG C, obtains meso-porous alumina C；
(4) weigh 5g meso-porous aluminas C and be dissolved in 0.625ml Pd (NO3)2In solution, 30min is stirred, under the conditions of 100 DEG C
10-24h of freeze-day with constant temperature, 2-4h of freeze-day with constant temperature under the conditions of 400-600 DEG C, obtain solid powder D, and powder solid D is institute
State catalyst.
(5) prepared catalyst is carried out as continuous flowable state fixed-bed micro-devices, flow chart is shown in accompanying drawing 1.Urge
The activity of agent is measured by the conversion ratio of methane.
Beneficial effects of the present invention are：1) meso-porous alumina prepared by the present invention is loaded Pd base catalyst and applied in vapour
On oily car and combustion gas class automotive vehicles, its discharge can meet state five and its above standard, can greatly reduce catalyst light-off
Temperature, effectively reduces motor vehicle NMHC and CH in cold-start phase4Discharge capacity, is to solve three-way catalyst product to meet state V
One of key technology of above discharge standard；2) noble metal is used in can substantially reducing corresponding catalyst prod due to the invention
Amount, reduces the product cost of raw material, has obvious competitive advantage on like product；3) in production preparation process, its technique
It is simple controllable, it is easy to which that production control, technology stability is good, and homogeneity of product also obtained guarantee, also under the conditions of reduction mass
Production cost；4) methane of the engine emission of combustion gas class is difficult oxidation catalysis burning, can be of the invention for CH4Engine is showed
Go out good disposal ability, the product of invention has been widely used weight, the emission treatment of light-duty combustion gas class engine.
Brief description of the drawings
Fig. 1 is methane catalytic combustion reaction unit flow chart；
Fig. 2 is catalyst Pd/Al2O3- 1 electron-microscope scanning figure；
Fig. 3 is catalyst Pd/Al2O3- 2 electron-microscope scanning figure.
Specific embodiment
The present invention is described in further details with reference to the accompanying drawings and detailed description, but protection scope of the present invention
It is not limited to the content.
Embodiment 1
(1) weigh 10g boehmites (technical grade, percentage of water loss is 15%), to be dissolved in 150mL deionized waters,
Obtain solution A；
(2) dust technology regulation solution PH is added to it after stirring 30min solution As, is adjusted to 3, obtain solution B；
(3) in B solution add 5g polyethylene glycol, stir 180min, under the conditions of 100 DEG C freeze-day with constant temperature 10h, 600
Freeze-day with constant temperature 2h under the conditions of DEG C, obtains meso-porous alumina C；
(4) weigh 5g meso-porous aluminas C and be dissolved in 0.625ml Pd (NO3)2In solution, 30min is stirred, under the conditions of 100 DEG C
Freeze-day with constant temperature 12h, the freeze-day with constant temperature 2h under the conditions of 400 DEG C, obtain solid powder D, and powder solid D is the catalyst, note
It is Pd/Al2O3-1.The specific surface area for measuring this catalyst by BET adsorption instruments still has 240m2/ g, pore volume is 0.42cc/g,
Aperture is 6.4nm.
(5) prepared catalyst is carried out into distribution detection as continuous flowable state fixed bed micro-reaction device (SGB), is surveyed
The conversion ratio for obtaining methane is 93.5%, the initiation temperature (T of methyl hydride combustion50) 305 DEG C are reduced to by 345 DEG C, the temperature burnt completely
Degree (T90) it is down to 395 DEG C by 450 DEG C.
Additionally, finding that the catalyst granules is scattered more uniform by Fig. 2, particle is smaller.
Thus show, according to above-mentioned steps, a kind of meso-porous alumina of the present invention loads the preparation of palladium-based catalyst
Method can prepare that high-specific surface area, catalytic active component decentralization are high, ageing resistace is good and have greater catalytic oxygen to methane
Change the catalyst of performance.
Embodiment 2
(1) weigh 10g boehmites (technical grade, percentage of water loss is 15%), to be dissolved in 150mL deionized waters,
Obtain solution A；
(2) dust technology regulation solution PH is added to it after stirring 30min solution As, is adjusted to 3, obtain solution B；
(3) in B solution add 5g polyethylene glycol, stir 180min, under the conditions of 100 DEG C freeze-day with constant temperature 10h, 600
Freeze-day with constant temperature 4h under the conditions of DEG C, obtains meso-porous alumina C；
(4) weigh 5g meso-porous aluminas C and be dissolved in 0.625ml Pd (NO3)2In solution, 30min is stirred, under the conditions of 100 DEG C
Freeze-day with constant temperature 24h, the freeze-day with constant temperature 4h under the conditions of 600 DEG C, obtain solid powder D, and powder solid D is the catalyst, note
It is Pd/Al2O3-2.Cross BET adsorption instruments and measure the specific surface area of this catalyst still with 201m2/ g, pore volume is 0.39cc/g, hole
Footpath is 5.9nm.
(5) prepared catalyst is carried out as continuous flowable state fixed-bed micro-devices, measures the conversion ratio of methane
It is 92.1%, the initiation temperature (T of methyl hydride combustion10) 310 DEG C are reduced to by 345 DEG C, the temperature (T for burning completely90) by 450 DEG C
It is down to 404 DEG C.
Additionally, finding that the catalyst granules is scattered more uniform by Fig. 3, particle is smaller.
Thus show, according to above-mentioned steps, a kind of meso-porous alumina of the present invention loads the preparation of palladium-based catalyst
Method can prepare that high-specific surface area, catalytic active component decentralization are high, ageing resistace is good and have greater catalytic oxygen to methane
Change the catalyst of performance.
Claims (8)
1. a kind of meso-porous alumina loads the preparation method of palladium-based catalyst, it is characterised in that specifically include following steps：
(1) boehmite of certain mass is weighed, is dissolved in deionized water, obtain solution A；
(2) dust technology regulation solution PH is added to it after stirring 30min solution As, obtains solution B；
(3) to certain mass template is added in B solution, 180min is stirred, is dried, calcines, obtain meso-porous alumina C；
(4) weigh certain mass C and be dissolved in Pd (NO3)2In solution, 30min is stirred, dry, calcine, obtain solid powder D, powder
Solid D is the catalyst.
2. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
10g intends thin aluminium stone for (technical grade, percentage of water loss is 15%, is dissolved in 150mL deionized waters in step (1).
3. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
The PH of solution B is adjusted to 3 in step (2).
4. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
Template used dose is 5g polyethylene glycol in step (3),.
5. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
Quality of alumina is weighed in step (4) for 5g, Pd (NO3)2Solution is 0.625mL, and wherein bullion content is 80g/L.
6. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
Dry condition is in step (3)：10-24h of freeze-day with constant temperature under the conditions of 100 DEG C；Calcination condition is：It is permanent under the conditions of 600 DEG C
Temperature dries 2-4h.
7. meso-porous alumina according to claim 1 loads the preparation method of palladium-based catalyst, it is characterised in that described
Dry condition is in step (4)：10-24h of freeze-day with constant temperature under the conditions of 100 DEG C；Calcination condition is：In 400-600 DEG C of bars
2-4h of freeze-day with constant temperature under part.
8. meso-porous alumina according to claim 1 loads the application of palladium-based catalyst, it is characterised in that be applied to methane
(CH4) catalysis burning.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107899570A (en) * | 2017-11-28 | 2018-04-13 | 秦皇岛天大环保研究院有限公司 | Integral catalyzer for super low concentration methyl hydride combustion and preparation method thereof |
| CN108201897A (en) * | 2018-02-01 | 2018-06-26 | 黑龙江省科学院石油化学研究院 | The method that ultrasonic wave added local reduction way prepares SBA-15 loaded nanometer palladium catalysts |
| CN108993560A (en) * | 2018-07-25 | 2018-12-14 | 昆明贵研催化剂有限责任公司 | A kind of water resistant, high temperature resistant methane oxidation catalyst and preparation method thereof |
| CN109304172A (en) * | 2017-11-16 | 2019-02-05 | 中国石油化工股份有限公司 | A kind of high dispersing microporous/mesoporous Ag-Al catalyst, preparation method and applications |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1170056A1 (en) * | 2000-07-05 | 2002-01-09 | Societe D'exploitation De Produits Pour Les Industries Chimiques-Seppic | Hydrogen absorbing composition, manufacturing method and use as optical fiber cable filling |
| CN103203233A (en) * | 2013-05-03 | 2013-07-17 | 云南大学 | Palladium-based catalyst for methane catalytic combustion and preparation of palladium-based catalyst |
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2016
- 2016-11-04 CN CN201610961978.3A patent/CN106732552A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1170056A1 (en) * | 2000-07-05 | 2002-01-09 | Societe D'exploitation De Produits Pour Les Industries Chimiques-Seppic | Hydrogen absorbing composition, manufacturing method and use as optical fiber cable filling |
| CN103203233A (en) * | 2013-05-03 | 2013-07-17 | 云南大学 | Palladium-based catalyst for methane catalytic combustion and preparation of palladium-based catalyst |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109304172A (en) * | 2017-11-16 | 2019-02-05 | 中国石油化工股份有限公司 | A kind of high dispersing microporous/mesoporous Ag-Al catalyst, preparation method and applications |
| CN107899570A (en) * | 2017-11-28 | 2018-04-13 | 秦皇岛天大环保研究院有限公司 | Integral catalyzer for super low concentration methyl hydride combustion and preparation method thereof |
| CN108201897A (en) * | 2018-02-01 | 2018-06-26 | 黑龙江省科学院石油化学研究院 | The method that ultrasonic wave added local reduction way prepares SBA-15 loaded nanometer palladium catalysts |
| CN108993560A (en) * | 2018-07-25 | 2018-12-14 | 昆明贵研催化剂有限责任公司 | A kind of water resistant, high temperature resistant methane oxidation catalyst and preparation method thereof |
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