CN107398303B

CN107398303B - Catalyst carrier for producing ethylene oxide and preparation method and application thereof

Info

Publication number: CN107398303B
Application number: CN201610333587.7A
Authority: CN
Inventors: 谷育英; 于海
Original assignee: Lanzhou Jrhc Chemical Technology Co ltd
Current assignee: Lanzhou Jinrunhongcheng New Material Technology Co ltd
Priority date: 2016-05-19
Filing date: 2016-05-19
Publication date: 2018-08-07
Anticipated expiration: 2036-05-19
Also published as: CN107398303A

Abstract

The invention relates to a catalyst carrier for producing ethylene oxide, a preparation method of the carrier, a catalyst prepared by applying the carrier, and application of the catalyst in producing ethylene oxide by oxidizing ethylene. The invention relates to a carrier which is composed of an inner alumina matrix and an outer modified material surface. The carrier is obtained by adopting the method of stirring, soaking and roasting the transition phase-containing alumina carrier precursor in the attapulgite-containing slurry. The carrier prepared by the invention has the most probable pore diameter of 1000-1600 nm, the proportion of pores with the diameter less than 50nm in the total pores is less than 5%, and the pore volume is 0.3-0.6 ml/g. The modified material on the outer surface of the carrier is effective to disperse the silver active sites and prevent sintering thereof. The catalyst prepared by the carrier can show high selectivity and longer service life when used for preparing ethylene oxide by ethylene epoxidation.

Description

It is a kind of to be used to produce catalyst carrier of ethylene oxide and its preparation method and application

Technical field

The present invention relates to a kind of catalyst carriers and preparation method thereof producing reacting ethylene oxide for ethylene epoxidizing With the catalyst and preparation method thereof for producing ethylene oxide made from the carrier.

Background technology

Ethylene epoxidizing is the production most important technique of ethylene oxide, and technological core is the silver catalyst of support type.Make Importance for loaded catalyst, technological improvement is exactly the improvement of carrier property, had at present a large amount of document and specially Profit reports the effort of scientific research personnel in this respect.It can be found by the analysis to document, the improvement of carrier is mainly concentrated It is modified both direction in the tuning of pore structure and surface.

Ethylene oxide is simplest cyclic ethers, and structure is very easy to open loop and other substance reactions, so chemical property It is very active.The ethylene oxide needs generated in the reaction of ethylene epoxidizing are expanded with faster diffusion rate out of caltalyst phase It is scattered in catalyst Outside Vapor, is otherwise easy to peroxidating.This just needs the duct of catalyst carrier that can be conducive to epoxy The quick diffusion of ethane, the macropore ratio for improving carrier are effectively means, and roasting temperature is specifically improved in carrier preparation It spends to realize.Especially when calcination temperature is more than 1200 DEG C, not only obtains the pore-size distribution of bigger but also be also obtained Be conducive to the inert α-Al of ethylene oxide generation₂O₃Surface.Although higher calcination temperature corresponds to the pore-size distribution of bigger, Also result in the low specific surface of carrier and low pore volume simultaneously so that the water absorption rate of carrier declines, and dipping prepares the difficulty of catalyst Degree increases.This is primarily due to high temperature by also macropore with suitable aperture is burnt by other during aperture and mesoporous elimination It loses.Patent CN103372466A, CN102397795A, CN102133545A use the diaspore knot of variety classes and granular size Conjunction mineralizer has obtained aperture and has accounted for the carrier of 60-90% in 0.5~2.5 μm of hole.Patent CN1361105A, CN1142154C is logical It crosses and the tin compound of 0.01-0.48% weight is added obtains diameter and account for the percentage of total pore volume more than 60 μm of hole being up to 20- 40% carrier.Although these methods can obtain the carrier that pore size is more biased towards big pore size distribution, but still contain and be largely unfavorable for The aperture of Reaction-diffusion terms and mesoporous, and these patents are absorbed in the activity and selectivity for improving catalyst more, to catalyst Service life has no effective improvement.

Ethylene epoxidizing catalysis reaction is happened on the Argent grain of carrier surface load, so size of the reaction to Argent grain It is required with distribution.Argent grain is undersized, and catalyst activity is excessively high, will selectively reduce；It is oversized, activity will under Drop is serious, and in particular with the use of catalyst, silver atoms can move on the surface of carrier, can finally be gathered into relatively large Argent grain, cause the inactivation of catalyst.This explanation is to reach suitable activity and highly selective, and there are one silver-colored dispersibilities The range of tuning hinders silver that can extend the service life of catalyst in the movement of carrier surface.Patent CN104981430A passes through The surface of alumina support is modified, some cavitys are formed on surface, the cavity on these carrier surfaces effectively capture and/or It is anchored Argent grain and prevents them from further moving.A kind of carrying is disclosed in CN1080211A, 1050778C, 1044416A The superficies and hole surface of body are applied with unbodied silica-alumina mixture coated with the side for reaching carrier surface modification Method, wherein the effect of Si contents in coating is also specifically described, Si/Al ratio 0.05-50.0g/g, this carrier has height Durability, it is ensured that industrial longer service life.In addition to this patent CN1223900A, 1117618C, 102029154A, 101360562A are also disclosed that when the compound of the non-oxide aluminium component in surface such as Si is right in some preferred section The performance of carrier has positive-effect influence.It is steady that these patents have had been found that other oxide components of oxidation aluminium surface use catalyst It qualitatively influences, and proposes the method utilized also for property, but improvement effect is very limited.On the one hand main cause is only Modification of the silica to surface is utilized, is on the other hand the influence to carrier pore structure during having ignored surface modification.

Invention content

The present invention provides a kind of methods preparing modified aluminum oxide carrier.Carrier prepared by this method is by inside Internal oxidation aluminum substrate and external modified material surface composition.The structure is will to contain transition by using heretofore described The alumina support precursor of phase stirs in the slurry containing alumina magnesia silicate, impregnate after the method that roasts and obtain.This Its average pore size of invention carrier obtained is not less than 1100nm, and the hole accounting less than 50nm is less than 20%.Carrier outer surface Modified material can effectively disperse silver-colored activated centre and hinder its sintering.

The method comprises the steps of firstly, preparing a kind of internal oxidation aluminum substrate containing transitional face, specific way are：The first step will be with The boehmite that 100 parts of quality meter mediates 0.5~3h of stirring in equal with peptizing agent, extrusion aid and pore creating material in kneader Even bulk.Wherein peptizing agent is mainly organic acid, including formic acid, acetic acid, propionic acid, ethanedioic acid, malonic acid, succinic acid, lemon At least one of at least one of acid and inorganic acid, including hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, meta-aluminic acid, peptizing agent is existed 5%~35% aqueous solution is formulated as in deionized water.Its feed postition be mediate stir during equably dropwise or Spray is added, and preferred condition is cannot to be less than the 60% of kneading time the addition time, and peptizing agent is 5~20 parts by mass. The effect of extrusion aid is to aid in carrier and is preferably molded, predominantly the sesbania powder of 200~500 mesh, and addition is by mass 0.5 ~3 parts.Extrusion aid can be added in kneader simultaneously with boehmite, can also uniformly be sprinkled into kneading after peptizing agent is added In machine.Pore creating material is lost by being burnt in gaseous form in the roasting process of carrier, to be formed in the carrier to external open Duct, be carbon dust, walnut shell powder, ammonium hydrogen carbonate, starch, graphene, polymethyl methacrylate and a variety of Methyl celluloses Element at least one of such as carboxymethyl cellulose, hydroxyethylmethylcellulose, hydroxypropyl methyl cellulose.Present invention discover that pore-creating Influence of the granular size of agent to carrier aperture is notable, has apparent correspondence, the granular size of pore creating material to exist between the two Between 200~1000 mesh, it can simultaneously be added or be added simultaneously with extrusion aid after peptizing agent or crowded helping with boehmite Agent is added before or after being added, and addition is 10~35 parts by mass.

Second step carries out forming processes to the dough after kneading, and moulding process may be used extrusion and be sliced or directly press again Sheetmolding.Shape can be Raschig ring, intermediate non-porous or multiple hole column.The outer diameter of Raschig ring is Particle Length is 5.5~8.5mm, median pore diameterThe outer diameter of cylindrical particle isParticle length is 6 ~8mm.

Processing is dried to particle after molding in third step.Drying mode can be selected but be not limited to crawler belt drying, heat Air purging, oven drying.No matter which kind of mode, drying temperature is 100~200 DEG C, wherein it is preferred that 110~150 DEG C, more preferably Be 120~140 DEG C.Drying time is 6~12h.

Final step roasts the blapharoplast after drying.Roasting apparatus can be Muffle furnace, tunnel oven or bell jar One kind in kiln.The atmosphere that carrier contacts in roasting can be air, inert atmosphere or the inertia for adding certain proportion oxygen Atmosphere.Inert atmosphere can be nitrogen, can also be argon gas or helium.The heating rate of roasting be 2~20 DEG C, preferably 3~15 DEG C, more preferably 3~8 DEG C.2~4h of holding is needed when temperature rises to 800~1000 DEG C, is then proceeded to according to heating speed before Rate rises to 1050~1450 DEG C, keeps 1~3h, cooled to room temperature.Since gamma-alumina is at 800 DEG C or more 1400 DEG C or less It can gradually change through the opposite α phases of θ, but be unlikely to be completely reformed into α phases again within a certain period of time, but it includes non-that can be in a kind of Stablize γ, θ phase and the existing state of the α phases of stabilization in transition.So finally just having obtained the internal oxidation containing transitional face Aluminum substrate.

The present invention also needs to prepare a kind of external modified material of the mineral slurry containing attapulgite as carrier.It is prepared Method is：By attapulgite, aluminium hydroxide and deionized water according to mass ratio 1~20:5~35：1000 are mixed and stirred for, process It is middle to keep the temperature of mixed liquor between 40~60 DEG C.It is gradually added dispersant in whipping process, dispersant and attapulgite Mass ratio is 1:2~40.Wherein dispersant be 2-amino-2-methyl-1-propanol, dimethyl -1- amino -1- ethyl alcohol, citric acid, At least one of polynary acid copolymer or homopolymer.Stop stirring after continuing 1~3h of stirring at low speed, is taken after standing 1~3h Then the uniform suspension of layer presses the mass ratio 1 with attapulgite:4~15 are added thickener, and wherein thickener changes for hydrophobicity Property alkali-soluble emulsion type or polyurethanes thickener.0.5~3h is persistently stirred after addition thickener to can be obtained containing attapulgite Mineral slurry.

Internal oxidation aluminum substrate containing transitional face is synthesized processing system by the present invention together with the mineral slurry containing attapulgite Obtain modified carrier.Internal oxidation aluminum substrate is immersed in the mineral slurry containing attapulgite first, it is slowly stirred 0.5~ 1h ensures that mineral slurry can uniformly touch all internal oxidation aluminum substrates, keep in the process the temperature of slurries 40~ 70 DEG C, 10~36h is impregnated after stirring.Concave convex rod crystal can be uniform and stable under the action of thickener be attached to α oxygen Change on aluminum substrate, simultaneously because concave convex rod crystal is in club shaped structure, width range is close with the pore size that aperture is mesoporous, is soaking Dispersant helps to be sufficiently separated between concave convex rod crystal during bubble, the crystal of separation be embedded into aperture and it is mesoporous in, block It is unfavorable for the channel pathway of reacting ethylene oxide diffusion.Next by the carrier impregnated from the mineral slurry containing attapulgite It filters to isolate and dries.Drying mode can select crawler belt drying, warm air blowoff or oven drying.Day may be used in baking oven Right gas heat supply, electrical heating, steam heating or infrared heating.In any way, 100~150 DEG C of drying temperature, wherein it is preferred that 110~150 DEG C, more preferably 120~140 DEG C.Finally the carrier after drying is roasted, it is excellent with 1~10 DEG C per minute It selects 2~5 DEG C of rate from room temperature to 1300~1450 DEG C and keeps 6~12h.It is carried using catalyst prepared by above method For body most probable pore size between 1000~1600nm, the ratio in wherein hole Zhan Zong hole of the aperture less than 50nm is less than 5%, Kong Rongjie In 0.3~0.6ml/g.Carrier forms the composite structure of apparent inner base and external modified material, inner base 95w% Above by α-Al₂O₃It constitutes；External modified material meets chemical general formula below：

AlMg_aSi_bO_x

A, b, x indicate each element atomic ratio respectively, and it be 0.2~1.5, x is by each oxide that wherein a, which is 0.1~0.9, b, The numerical value that oxygen determines.

The invention further relates to the ethylene production ethylene oxide prepared on the basis of a kind of carrier prepared in above-mentioned method Catalyst, preparation method is：The carrier for taking a certain amount of preceding method to prepare first dries 3h at 120 DEG C, takes out cooling After test its water absorption rate, the amount of preparation of maceration extract is calculated by the quality and water absorption rate and silver load capacity of carrier.Next, At least one of silver nitrate, silver carbonate, actol are dissolved in deionized water, then carried out with the aqueous solution containing oxalate anti- It should obtain silver oxalate precipitate.Aqueous solution containing oxalate is oxalic acid or oxalic acid aqueous ammonium.Silver oxalate precipitate is filtered and is taken out, so Afterwards suction filtration to filtrate is washed repeatedly with deionized water to be in neutrality.Silver oxalate after washing is dissolved in into organic amine such as ethylenediamine, ethyl alcohol In the aqueous solution of or mixtures thereof amine, 1,3- propane diamine, then be added alkali metal or and base earth metal promoter be made maceration extract. Wherein alkali metal is at least one of Li, K, Cs and Rb, addition be by mass Ag constituent contents in maceration extract 0.1~ 1%.Alkaline-earth metal is one or more mixtures in Ca, Sr, Ba, and addition is Ag constituent contents in maceration extract by mass 0.05~0.5%.Maceration extract is placed 0.5~1h and is stablized, while the temperature of maceration extract is maintained at 20~40 DEG C.Later In normal pressure or vacuum condition volumetric or excessive impregnated carrier.Carrier after dipping carries out drying and processing, furnace drying method and item Part and internal oxidation aluminum substrate of the foregoing description containing transitional face are identical as the synthesis condition of the mineral slurry containing attapulgite, drying It is handled 2-30 minutes in 150-500 DEG C of temperature in air atmosphere afterwards and obtains catalyst.Catalyst obtained is used for second after activation Alkene epoxidation epoxy ethane can show the highly selective and longer cycle of operation.

Due to the adoption of the above technical scheme, the beneficial effects of the present invention are：

(1) embedded concave convex rod crystal is made fully to be combined with the aluminium oxide of transition state by roasting, it will be between concave convex rod crystal Excessively high specific surface sintering, eliminates transition state of alumina, is allowed to be completely reformed into stable α phases, while embedding in this process Enter the outside of concave convex rod crystal of aluminium oxide and the aluminium oxide of surrounding is formed in the carrier surface protrusion of magnesium alumino-silicate, these Protrusion on alpha-aluminium oxide flat crystal particle is a significant increase the roughness on its surface, effectively Argent grain can be hindered to exist Movement on carrier surface and reunion have delayed silver-colored active sintering, have extended the service life of catalyst.

(2) carrier prepared by the present invention is used to prepare for the alpha-aluminium oxide carrier of no external modified material The selectivity of ethylene oxide can improve 1~6%, and the decay of activity rate of successive reaction 1000h can averagely decline 0.7%, table Reveal longer catalyst life.

Specific implementation mode

[characterizing method]

A. specific surface area：

Surface area described in the present invention refers in particular to B.E.T surface areas, can pass through any feasible method and reliable instrument Device measures, but it is here preferred that using Merck ＆ Co., Inc of the U.S. 2020 instruments of ASAP and standard GB/T19587-2004 In method measure.

B. pore structure：

Since most of hole is macropore in carrier, reliable result can just only be obtained using pressure mercury.Here pore structure Characterization includes pore-size distribution, Kong Rong and porosity.The equipment used in embodiment is U.S. Mike mercury injection apparatus AutoPore9500 Mercury injection apparatus, test method is with reference to GB/T 21650.1-2008.

[evaluating catalyst experimental method]

A. reaction unit：

Reaction unit is mainly by gas mixing reservoir, mass flowmenter, pressure sensor, reactor and counterbalance valve five It is grouped as.Reaction raw materials according to reaction condition gas mixing reservoir allocate, then by mass flowmenter measure control after Be passed through in reactor and reacted, reactor byStainless steel tube, insideThermal couple casing pipe and electricity plus Hot device composition, reaction pressure pass through counterbalance valve and pressure sensor adjusting control.

B. reaction condition：

Air speed=5000h^-1；Reaction pressure=1.60Mpa；

Reaction raw materials：Ethylene=30mol% oxygen=8mol%CO₂=3mol%N₂For Balance Air, wherein containing about 4~ The monochlorethane of 6ppm.

C. analysis method：

Reaction gas passes to gas-chromatography by online pipeline and is analyzed after standby pressure valve.

D. computational methods：

The present invention is described further with reference to embodiment, but the scope of the invention is not limited to these examples.

[embodiment]

(1) internal oxidation aluminum substrate

Matrix A

1000g boehmites are weighed with electronic balance, the carbon dust of 67.9g1000 mesh is poured into kneader and mixed. 8.6g citric acids and 2.8ml concentrated nitric acids are weighed, peptization agent solution is made into 30ml deionized waters, is uniformly sprayed in 36 minutes On the material of kneader, the sesbania powder 30g of 200 mesh is then added, is taken out after persistently mediating 36 minutes.Material after kneading is added Enter pelletizing after double screw banded extruder squeezes out and forms outer diameterMesoporousThe Raschig ring shape of length 6.5mm Grain.

Shaped granule is put into and is passed through the hot-air for being heated to 140 DEG C in tube furnace, dry 6h.Particle after drying is put into In Muffle furnace, roasted in air atmosphere.900 DEG C are risen to the rate of 8 DEG C/min, constant temperature 2h is then followed by with before Identical heating rate lifts temperature to 1350 DEG C, and stopping heating after holding 2h is allowed to cooled to room temperature, obtains internal oxidation aluminium Matrix A.

Matrix B

Preparation method and step and internal oxidation aluminum substrate A are essentially identical, and difference is：Peptization agent solution be by 27.5g succinic acid, the 22.5ml concentrated sulfuric acids and 171ml deionized waters are formulated.Peptization agent solution will uniformly add in 43 minutes Enter.Sesbania powder addition is 10g, and mesh number is 500 mesh.Pore creating material is the walnut powder of 400 mesh of 240.9g, and is that peptization is being added It is added simultaneously with extrusion aid after agent.Persistently mediate 1.5h.Shaped granule is outer diameterMesoporousLength The Raschig ring shape of 8.0mm.Roasting heating rate is 5 DEG C/min.

Matrix C

Preparation method and step and internal oxidation aluminum substrate A are essentially identical, and difference is：Peptization agent solution is by 3.5g Succinic acid, 5.0ml concentrated hydrochloric acids and 72ml deionized waters are formulated.Peptization agent solution will be uniformly added into 38 minutes.It helps crowded Agent sesbania powder addition is 5g, and mesh number is 300 mesh.Pore creating material is the starch of 1000 mesh of 133.1g.Pore creating material is added in peptizing agent It uniformly is sprinkled into kneader, extrusion aid is then added.Persistently mediate 1.5h.Outer diameter is shaped to using tablet press machineLength The non-porous cylindrical pellet in the centre of 6.0mm.Using being put into Muffle furnace in the nitrogen containing 10% oxygen after 190 DEG C of dry 12h of baking oven Under gas atmosphere, 900 DEG C, constant temperature 2h are risen to 10 DEG C/min, is then followed by and lifts temperature to 1250 DEG C with identical heating rate before, Stopping heating being allowed to cooled to room temperature after keeping 2h, obtains internal oxidation aluminum substrate C.

Matrix D

Weigh up 1000g boehmites, the extrusion aid sesbania powder of 400 mesh of 15g, 400 mesh 64.8g walnut shell powders and 92.4g carboxymethyl celluloses, which pour into kneader, to be mixed.Weigh 15.5g citric acids and 11.9g meta-aluminic acids, with 64ml go from Sub- water is made into peptization agent solution, is uniformly sprayed on the material of kneader in 44 minutes, is taken out after persistently mediating 2h.It will mediate Materials result afterwards is shaped to outer diameterLength 7.5mm, centre have 3The cylindrical pellet in hole.

Shaped granule is put into and is passed through 110 DEG C of hot-air in tube furnace, dry 12h.Particle after drying is put into Muffle In stove, roast in a nitrogen atmosphere.800 DEG C, constant temperature 3h are risen to the rate of 2 DEG C/min, is then followed by with identical liter before Warm rate lifts temperature to 1150 DEG C, and stopping heating after holding 3h is allowed to cooled to room temperature, obtains internal oxidation aluminum substrate D.

(2) mineral slurries

The preparation steps of mineral slurries are substantially identical：By M₁G attapulgites, M₂G aluminium hydroxides and 1500ml deionizations Water is uniformly mixed after weighing, and keeps mixed liquor in temperature t in the process₁℃.M is gradually added in mixed process₃G dispersants.Continue low Speed stirring T₁After stop, the uniform suspension in upper layer is taken after standing, M is then added₄G thickeners.Persistently stir T₂It can be obtained and contain The mineral slurry of attapulgite.

Different mineral slurries are made from species are added by different additions, specific performance is shown in Table 1：

(wherein #1 thickeners are the RM-8W polyurethane thickeners of Rhom and Hass of the U.S., and #2 thickeners are U.S. Luo Men The TT-935 hydrophobically-modified alkalis of Haars Co., Ltd are swollen association thickener.)

Table 1

(3) carrier

Alpha-aluminium oxide matrix containing transitional face is synthesized into the load that processing is made modified together with the mineral slurry containing attapulgite Body.Internal oxidation aluminum substrate is immersed in the mineral slurry containing attapulgite first, is slowly stirred, ensures that mineral slurry can All internal oxidation aluminum substrates are uniformly touched, keep the temperature of slurries to be impregnated after some temperature, stirring in the process Regular hour.Modified support is formed by dry and roasting later.

Directly internal oxidation aluminum substrate is roasted again and is made as comparison vehicle.

Specific performance is listed in table 2.

(4) catalyst

500g carriers are taken, 3h is dried at 120 DEG C, test its water absorption rate after taking out cooling, the quality by carrier and water suction The amount of preparation of maceration extract is calculated in rate and the silver load capacity of needs.Next, by silver nitrate, silver carbonate, actol At least one silver salt is dissolved in deionized water, and silver oxalate precipitate is obtained with the reactant aqueous solution containing oxalate.Water containing oxalate Solution is oxalic acid or oxalic acid aqueous ammonium.Silver oxalate precipitate is filtered and is taken out, then washs suction filtration repeatedly with deionized water to filter Liquid is in neutrality.Silver oxalate after washing is dissolved in into the water-soluble of or mixtures thereof organic amine such as ethylenediamine, ethanol amine, 1,3- propane diamine In liquid, then be added alkali metal or and base earth metal promoter be made maceration extract.Wherein alkali metal be Li, K, Cs and Rb in extremely Few one kind, addition are 0.1~1% of Ag constituent contents in maceration extract by mass.Alkaline-earth metal is one in Ca, Sr, Ba Kind or a variety of mixtures, addition are 0.05~0.5% of Ag constituent contents in maceration extract by mass.Maceration extract places 0.5 ~1h is stablized, while the temperature of maceration extract is maintained at 20~40 DEG C.Load is being impregnated under normal pressure or vacuum condition later Body.Carrier after dipping carries out drying and processing, furnace drying method and condition and internal oxidation aluminum substrate of the foregoing description containing transitional face It is identical as the synthesis condition of the mineral slurry containing attapulgite, after drying successively in 150-500 DEG C of air stream and water content It is handled 2-30 minutes in vapor-air stream of 1%-100% and obtains catalyst.

The catalyst of preparation carries out contrast test with evaluating apparatus above-mentioned and process conditions.

Specific preparation condition and test result are shown in Table 3.

Claims

1. a kind of catalyst carrier being used to prepare ethylene oxide, it is characterised in that the carrier is by internal oxidation aluminum substrate and outside Modified material forms, and the internal oxidation aluminum substrate 95w% or more is by α-Al₂O₃It constitutes, external modified material meets below Chemical general formula：

AlMg_aSi_bO_x

A, b, x indicate the atomic ratio of each element respectively, and it be 0.2~1.5, x is by the oxygen of each oxide that wherein a, which is 0.1~0.9, b, The numerical value of decision.

2. catalyst carrier as described in claim 1, it is characterised in that a is 0.1~0.3.

3. catalyst carrier as described in claim 1, it is characterised in that b is 0.2~0.5.

4. catalyst carrier as described in claim 1, it is characterised in that the most probable pore size of the catalyst carrier 1000~ Between 1600nm.

5. catalyst carrier as described in claim 1, it is characterised in that the wherein ratio in hole Zhan Zong hole of the aperture less than 50nm Less than 5%.

6. catalyst carrier as described in claim 1, it is characterised in that Kong Rong is between 0.3~0.6mL/g.

7. according to the preparation method of any one of claim 1~6 carrier, it is characterised in that include the following steps:

A) the internal oxidation aluminum substrate containing transitional face is prepared；

B) mineral slurries containing attapulgite are prepared, step includes：

1) attapulgite, aluminium hydroxide and deionized water are mixed and stirred for；

2) dispersant and thickener are gradually added in whipping process；

C) the internal oxidation aluminum substrate containing transitional face stirred in the mineral slurries containing attapulgite, impregnated；

D) the internal oxidation aluminum substrate after immersion is detached from the mineral slurries containing attapulgite, is then dried and roasts Processing.

8. preparation method as claimed in claim 7, wherein the step of preparing the internal oxidation aluminum substrate containing transitional face includes：

A) boehmite and peptizing agent, extrusion aid and pore creating material are mediated into stirring in uniform bulk in kneader；

B) dough after mediating carries out forming processes；C) processing is dried in carrier；D) carrier after drying is roasted.

9. preparation method as claimed in claim 8, it is characterised in that each component is respectively in mass in step a：100 parts quasi- Boehmite, 5~20 parts of peptizing agents, 0.5~3 part of extrusion aid, 10~35 parts of pore creating materials.

10. preparation method as claimed in claim 8, it is characterised in that the peptizing agent described in step a is organic acid formic acid, second At least one of acid, propionic acid, ethanedioic acid, malonic acid, succinic acid, citric acid and inorganic acid hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, The peptizing agent is formulated as 5%~35% aqueous solution by least one of meta-aluminic acid in deionized water.

11. preparation method as claimed in claim 8, it is characterised in that the peptizing agent described in step a is to mediate stirring In the process equably dropwise or spray be added.

12. preparation method as claimed in claim 8, it is characterised in that the extrusion aid described in step a is 200~500 purposes Sesbania powder.

13. preparation method as claimed in claim 8, it is characterised in that the pore creating material described in step a is carbon dust, walnut shell Powder, ammonium hydrogen carbonate, starch, graphene, polymethyl methacrylate, carboxymethyl cellulose, hydroxyethylmethylcellulose, hydroxypropyl At least one of methylcellulose.

14. preparation method as claimed in claim 8, it is characterised in that pore creating material granular size described in step a 200~ Between 1000 mesh.

15. preparation method as claimed in claim 8, it is characterised in that the pore creating material described in step a can be with quasi- thin water aluminium Stone is added simultaneously or is added with extrusion aid after peptizing agent or is added before or after extrusion aid is added simultaneously.

16. preparation method as claimed in claim 8, it is characterised in that extrusion can be used again in the forming processes described in step b Slice or direct tablet compressing molding.

17. preparation method as claimed in claim 8, it is characterised in that the shape after forming processes described in step b can be Raschig ring, intermediate non-porous or multiple hole column.

18. preparation method as claimed in claim 17, it is characterised in that the outer diameter of Raschig ring is 5.5-8.5mm, particle length Outer diameter for 5.5~8.5mm, 1.5~5.5mm of median pore diameter, cylindrical particle is 6-8mm, and particle length is 6~8mm.

19. preparation method as claimed in claim 8, it is characterised in that drying mode can be selected but be not limited to carry out in step c Drying, warm air blowoff and oven drying；100~200 DEG C of drying temperature, drying time are 6~12h.

20. preparation method as claimed in claim 8, it is characterised in that atmosphere when being roasted in step d can be air, inertia Atmosphere or mixed atmosphere containing air and inert gas.

21. preparation method as claimed in claim 8, it is characterised in that the heating rate roasted in step d is 2~20 DEG C of heatings To 800~1000 DEG C, 2~4h is kept, then rises to 1050~1450 DEG C according to heating rate before, keeps 1~3h.

22. the preparation method of carrier, step include as recited in claim 7：A) by attapulgite, aluminium hydroxide and deionization Water is mixed and stirred for；B) dispersant and thickener are gradually added in whipping process；It is characterized in that attapulgite, aluminium hydroxide with The mass ratio of deionized water is 1~20:5~35:1000.

23. the preparation method of the carrier as described in claim 22, it is characterised in that the dispersant is 2- amino -2- first At least one of base -1- propyl alcohol, dimethyl -1- amino -1- ethyl alcohol, citric acid, polynary acid copolymer or homopolymer, addition With the mass ratio 1 of attapulgite:2~40.

24. the preparation method of the carrier as described in claim 22, it is characterised in that be added after dispersant continue stirring at low speed 1~ Stop stirring after 3h, the uniform suspension in upper layer is taken after standing 1~3h, then persistently stirring 0.5~3h after addition thickener obtains To the mineral slurry containing attapulgite.

25. the preparation method of the carrier as described in claim 22, it is characterised in that the thickener is hydrophobic modified alkali Latex emulsion of solubleness type or polyurethanes thickener.

26. a kind of catalyst for by ethylene production ethylene oxide, it is characterised in that the catalyst is by claim 1 to 6 Any carrier and argentiferous active component composition, the active component of the argentiferous is carried on the carrier.

27. a kind of method preparing catalyst as claimed in claim 26, this method include：A) by the aqueous solution of silver salt compound It carries out that silver oxalate precipitate is obtained by the reaction with the aqueous solution containing oxalate；B) silver oxalate after washing is dissolved in into Amine Solutions, and Be added alkali metal or and base earth metal promoter be made maceration extract；C) by any one of claim 1 to 6 carrier impregnation in institute In the maceration extract stated；D) catalyst is obtained after the activated processing of carrier after impregnating.

28. the method for preparing catalyst as described in claim 27, wherein the aqueous solution of the silver salt compound is by nitre At least one of sour silver, silver carbonate, actol, which are dissolved in deionized water, to be formulated.

29. the method for preparing catalyst as described in claim 27, wherein the aqueous solution containing oxalate be oxalic acid or Oxalic acid aqueous ammonium.

30. the method for preparing catalyst as described in claim 27, wherein the Amine Solutions are ethylenediamine, ethyl alcohol The aqueous solution of or mixtures thereof amine, 1,3- propane diamine.

31. the method for preparing catalyst as described in claim 27, wherein the alkali metal be in Li, K, Cs and Rb extremely Few one kind, addition are 0.1~1wt % of Ag constituent contents in maceration extract by mass.

32. the method for preparing catalyst as described in claim 27, wherein the alkaline-earth metal is one in Ca, Sr, Ba Kind or a variety of mixtures, addition are 0.05~0.5wt % of Ag constituent contents in maceration extract by mass.

33. the method for preparing catalyst as described in claim 27, wherein maceration extract need 0.5~1h of placement before impregnated carrier Stablized, while the temperature of maceration extract is maintained at 20~40 DEG C in dipping process.

34. the method for preparing catalyst as described in claim 27, it is characterised in that maceration extract is under normal pressure or vacuum condition Isometric or excessive impregnated carrier.

35. the method for preparing catalyst as described in claim 27, it is characterised in that in air after the carrier drying after dipping Obtain catalyst within activation process 2-30 minutes in 150-500 DEG C of temperature under atmosphere.