CN109850939A - Preparation method of disordered mesoporous nano titanium dioxide - Google Patents
Preparation method of disordered mesoporous nano titanium dioxide Download PDFInfo
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Abstract
The invention relates to a preparation method of disordered mesoporous nano titanium dioxide, which comprises the following steps: a, taking titanium acidolysis solution in the production of titanium dioxide by a sulfuric acid method, adding part of the titanium acidolysis solution into sodium hydroxide solution, and stirring to obtain primary mixed solution; b, adding the residual titanium acidolysis solution into the mixed solution, and stirring to obtain a secondary mixed solution; heating the white suspension to boiling, filtering and washing after heat preservation to obtain a filter cake, and pulping the filter cake to obtain slurry; e, heating the slurry, adding ammonia water, adjusting the pH value to 5.0-8.0, dehydrating the sol, and then putting the sol into a muffle furnace for calcining to obtain granular titanium dioxide; and f, crushing the granular titanium dioxide to obtain the disordered mesoporous nano titanium dioxide with the annular structure. The method has the advantages of simple operation, low cost, no pollution and easy realization of industrialization.
Description
Technical field
Present invention relates particularly to a kind of preparation methods of unordered mesohole nano-titanium dioxide, belong to denitration honeycomb catalyst load
Antibody Production Techniques field.
Background technique
TiO2 has high chemical stability, and corrosion-resistant and mithridatism is shown huge latent as catalyst carrier material
Power and permanent vitality.From the point of view of current research report, the research about mesoporous TiO 2 preparation has gone through nothing
The preparation of sizing mesoporous TiO 2 and the preparation of semi-crystalline state mesoporous TiO 2, current research focus concentrate on having height
The research of the ordered mesoporous titanium dioxide of crystalline state skeleton structure.But the orderly ducts of certain catalysis reacting middle catalysts not yet
Conducive to the diffusion of reactant, cause the catalytic activity of catalyst lower.No matter in mesoporous catalyst preparation or catalytic applications,
Diffusion problem of the substance in mesopore orbit how is solved, is the key that mesoporous catalyst development.This requires as catalyst
The TiO2 of carrier, with no ordered meso-porous structure, i.e., duct between particle and particle by accumulating, aperture size wider distribution,
Duct is complex-shaped, irregularly, is not interconnected.
No ordered meso-porous structure titanium dioxide has high specific surface area and suitable aperture, can provide in SCR catalysis
More adsorption sites make reactant gather catalyst surface, improve the probability that reactant is contacted with activated centre.It is opposite simultaneously
In the catalyst carrier of ordered mesopore structure, diffusion problem of the reactant in mesopore orbit is solved, mentions catalytic efficiency obviously
It rises.In addition, possessing very high mechanical strength without ordered meso-porous structure titanium dioxide, thermal stability with higher can be carried on gold
Belong to plate, ceramics, on fiberglass substrate, plate, honeycomb or corrugated plate shape be made, is finally integrated in steel shell, composition SCR is anti-
Answer the entirety of device.
Chinese patent 201711450236.5 discloses a kind of synthetic method of efficient mesoporous nano TiO2 and its in latex
Application method in paint is original with tetrabutyl titanate TBOT solution, polyethylene glycol 400, cetyl trimethylammonium bromide CTAB
Material prepares the mesoporous nano TiO2 with orderly mesoporous channel, which is applied in emulsion paint, have compared with
Strong reinforcing, high catalytic activity, enhance the stability of emulsion paint film, has potent kill to the bacterium in room air
Effect is effectively improved indoor sanitation situation the effect of assigning emulsion paint long acting antibiotic, sterilize.But prepared by the mesoporous nano TiO2
Ingredient requirement is high in the process, mesoporous micro- orderly duct of preparation, is unfavorable for the fast of reactant under the conditions of denitrating catalyst high temperature
Speed diffusion, is not suitable for the carrier of denitrating catalyst.
Chinese patent 201610077118.3 discloses a kind of preparation of two-dimensional layer titanium dioxide nano photocatalysis material
Method prepares laminar titanium dioxide photocatalyst in polytetrafluoroethylene (PTFE) autoclave with coprecipitation and hydro-thermal method.It should
Method uses NaOH as raw material during preparing nano-titanium dioxide, introduces Na ion, unfavorable to denitrating catalyst, while its
The titanium dioxide of preparation is layer structure, is unfavorable for reactant in denitration catalyst reaction process and spreads, and the high requirements on the equipment, and
It takes a long time, is not easy to realize industrialization.The nano-titanium dioxide of this method preparation is used for photocatalysis, is not suitable for denitration catalyst
Agent.
Chinese patent 201510378201.X discloses the preparation method of the hollow full meso-porous nano fiber of TiO2, the nanometer
Fiber has porous structure, including mesoporous, and has both hollow and full meso-hole structure.The invention, which passes through, adds suitable paraffin oil,
By electrostatic spinning, presoma is coated on inside by continuous phase in the effect of electrostatic force, is effectively synthesized while having both hollow and complete
Mesoporous TiO2 nanofiber, although the full meso-porous nano fiber TiO2 of this method synthesis is as photocatalyst applications in photocatalytic water
Hydrogen manufacturing, and there is fabulous high efficiency and stability, but be not suitable for denitrating catalyst, synthesis process is complicated, and equipment precision is wanted
It asks high, is not easy to realize industrialization.
Summary of the invention
To solve the above problems, the present invention provides a kind of preparation method of unordered mesohole nano-titanium dioxide, specific side
Case the following steps are included:
Acidolysis titanium liquid when a takes sulfuric acid method titanium pigment to produce, is warming up to 70-90 DEG C, and 70-90 DEG C of hydrogen is added in partial acid digestion titanium liquid
In sodium hydroxide solution, 90-120 DEG C is warming up to after stirring, heat preservation 0-30min obtains level-one mixed liquor；
Acidolysis titanium liquid remaining in step a is added in the mixed liquor that step a is obtained by b, stirs to get second level mixed liquor；
The second level mixed liquor that step b is obtained is warming up to boiling by c, heat preservation to solution it is graying after, obtained after standing 10min-60min
White suspension;
The white suspension that d obtains step c opens stirring, is warming up to boiling, after keeping the temperature 2h-4h, is filtered and washes, obtain
To filter cake, filter cake is beaten to obtain slurries；
The obtained slurries of step d are warming up to 60-120 DEG C by e, and ammonium hydroxide is added, and adjust pH to 5.0-8.0, and observation slurries form molten
Gluey state keeps the temperature 2-6h, after being dehydrated to colloidal sol, is put into 400 DEG C of -600 DEG C of calcinings in Muffle furnace, obtains graininess titanium white
Powder；
F the graininess titanium dioxide that step e is obtained is crushed after to get the unordered meso-porous nano titanium dioxide with cyclic structure
Titanium.
Further, the acidolysis titanium liquid in step a, wherein TiO2Concentration be 180g/L-210g/L；Ti3+Concentration be
0.7-2.7g/L；Fe2+Mass ratio with TiO2 is 0.25-0.35；F value is 1.55-2.00；Specific gravity is 1.521-1.552g/
cm3。
Further, sodium hydroxide mass concentration is 8%-16% in step a.
Further, the total volume ratio of sodium hydroxide solution and acidolysis titanium liquid is 100:300~200:300 in step a.
The present invention has below beneficial to point: for 1. present invention using the black titanium liquid of sulfate process titanium dioxide production as raw material, raw material is honest and clean
Valence is easy to get, it is desirable that the concentration of sodium hydroxide and titanyl sulfate is being prepared by adjusting the volume ratio of sodium hydroxide and titanyl sulfate
After addition ammonium hydroxide makes metatitanic acid form colloidal sol in denitration titanium dioxide process, dehydration, calcining are prepared de- with cyclic structure
The unordered mesohole nano-titanium dioxide of denox catalyst.
2. the aperture of unordered mesohole nano-titanium dioxide prepared by the present invention can be controlled in 20nm or so, pore-size distribution is narrow
Narrow, morphology microstructure is evenly dispersed ring structure.Unordered mesoporous TiO 2 has high specific surface area and suitable aperture,
More adsorption sites can be provided in SCR catalysis, reactant is made to gather catalyst surface, improve reactant and activated centre
The probability of contact.
3. the present invention is low for equipment requirements, the unordered mesohole nano-titanium dioxide particle diameter distribution prepared is uniform, ring junction
Structure is evenly dispersed, conducive to diffusion of the reactant in mesopore orbit, improves the catalytic activity of catalyst, while reducing denitration catalyst
The shrinking percentage of agent improves the yield rate of catalyst, and extrusion, forming process suitable for denitrating catalyst production improve catalyst
Mechanical strength and thermal stability.
4. the present invention is to rely on the raw material of industry, easy to operate, process flow is short, and environmental pollution is small, work easy to accomplish
Industry metaplasia produces.
Detailed description of the invention
Fig. 1 is the scanning electron microscope (SEM) photograph of unordered mesohole nano-titanium dioxide prepared by embodiment 1；
Fig. 2 is the scanning electron microscope (SEM) photograph of unordered mesohole nano-titanium dioxide prepared by embodiment 2；
Fig. 3 is the scanning electron microscope (SEM) photograph of unordered mesohole nano-titanium dioxide prepared by embodiment 3.
Specific embodiment
Embodiment 1
A, which takes, meets titanium liquid index TiO2:180g/L；Ti3+:0.7g/L；Fe2+/TiO2:0.25；F value: 1.55；Specific gravity:
1.521g/cm3Technical grade titanium liquid, be warming up to 70 DEG C；
It is 8% that b, which prepares naoh concentration, is warming up to 70 DEG C;
In a 1/10 titanium liquid is added in sodium hydroxide solution c, and after mixing evenly, temperature rises to 90 DEG C, heat preservation 15min curing；
NaOH:TiO is pressed in this example of d2=100: 300(volume ratio) ratio mixing technical grade titanium liquor and sodium hydroxide it is molten
Liquid；
E residual titanium liquid in step a is added in the mixed liquor of step c, uniformly mixes；
The mixed liquor of step e is warming up to boiling by f, heat preservation to solution it is graying after, stop stirring 10min;
Suspension white in step f is opened stirring by g, is warming up to boiling, is kept the temperature 2h；
After h washes step g reacting rear material, filter cake prepares slurries, is warming up to 80 DEG C, and ammonium hydroxide is added, adjust pH to
5.0, observation slurries form collosol state, keep the temperature 2h, after being dehydrated to solution, are put into 400 DEG C of calcining 2h in Muffle furnace；
I step h graininess titanium dioxide is crushed after to get the unordered mesohole nano-titanium dioxide with cyclic structure.
The unordered mesohole nano-titanium dioxide of j step i preparation detects morphology microstructure by scanning electron microscope.
Embodiment 2
A, which takes, meets titanium liquid index TiO2:190g/L；Ti3+:0.9g/L；Fe2+/TiO2:0.31；F value: 1.80；Specific gravity: 1.525
Technical grade titanium liquid, is warming up to 85 DEG C；
It is 16% that b, which prepares naoh concentration, is warming up to 80 DEG C;
In a 1/10 titanium liquid is added in sodium hydroxide solution c, and after mixing evenly, temperature rises to 100 DEG C, and heat preservation 15min is ripe
Change；
NaOH:TiO is pressed in this example of d2=140: 300(volume ratio) ratio mixing technical grade titanium liquor and sodium hydroxide it is molten
Liquid；
E residual titanium liquid in step a is added in the mixed liquor of step c, stirs 15min, uniformly mixes；
The mixed liquor of step e is warming up to boiling by f, heat preservation to solution it is graying after, stop stirring 30min;
Suspension white in step f is opened stirring by g, is warming up to boiling, is kept the temperature 3h；
After h washes step g reacting rear material, filter cake prepares slurries, is warming up to 60 DEG C, and ammonium hydroxide is added, adjust pH to
7.2, observation slurries form collosol state, keep the temperature 3h, after being dehydrated to solution, are put into 480 DEG C of calcining 2h in Muffle furnace；
I step h graininess titanium dioxide is crushed after to get the unordered mesohole nano-titanium dioxide with cyclic structure.
Unordered mesohole nano-titanium dioxide prepared by step i detects morphology microstructure by scanning electron microscope.
Embodiment 3
A, which takes, meets titanium liquid index TiO2:210g/L；Ti3+:2.7g/L；Fe2+/TiO2:0.35；F value: 2.00；Specific gravity: 1.552
Technical grade titanium liquid, is warming up to 90 DEG C；
It is 16% that b, which prepares naoh concentration, is warming up to 90 DEG C;
In a 1/10 titanium liquid is added in sodium hydroxide solution c, and after mixing evenly, temperature rises to 120 DEG C, and heat preservation 30min is ripe
Change；
NaOH:TiO is pressed in this example of d2=200: 300(volume ratio) ratio mixing technical grade titanium liquor and sodium hydroxide it is molten
Liquid；
E residual titanium liquid in step a is added in the mixed liquor of step c, stirs 15min, uniformly mixes；
The mixed liquor of step e is warming up to boiling by f, heat preservation to solution it is graying after, stop stirring 60min;
Suspension white in step f is opened stirring by g, is warming up to boiling, is kept the temperature 4h；
After h washes step g reacting rear material, filter cake prepares slurries, is warming up to 120 DEG C, and ammonium hydroxide is added, adjust pH to
8.0, observation slurries form collosol state, keep the temperature 6h, after being dehydrated to solution, are put into 600 DEG C of calcining 2h in Muffle furnace；
I step h graininess titanium dioxide is crushed after to get the unordered mesohole nano-titanium dioxide with cyclic structure.
The unordered mesohole nano-titanium dioxide of j step i preparation detects morphology microstructure by scanning electron microscope.
The unordered mesohole nano-titanium dioxide that embodiment 1-3 is prepared it can be seen from Fig. 1-3 has apparent cyclic annular knot
Structure, in 15-35nm, pore-size distribution is narrow in aperture, and morphology microstructure is evenly dispersed ring structure, has unordered mesopore orbit,
Conducive to diffusion of the reactant in mesopore orbit, the catalytic activity of catalyst is improved, while reducing the shrinking percentage of denitrating catalyst.
Claims (4)
1. a kind of preparation method of unordered mesohole nano-titanium dioxide, which comprises the following steps:
Acidolysis titanium liquid when a takes sulfuric acid method titanium pigment to produce, is warming up to 70-90 DEG C, and 70-90 DEG C of hydrogen is added in partial acid digestion titanium liquid
In sodium hydroxide solution, 90-120 DEG C is warming up to after stirring, heat preservation 0-30min obtains level-one mixed liquor；
Acidolysis titanium liquid remaining in step a is added in the mixed liquor that step a is obtained by b, stirs to get second level mixed liquor；
The second level mixed liquor that step b is obtained is warming up to boiling by c, heat preservation to solution it is graying after, obtained after standing 10min-60min
White suspension;
The white suspension that d obtains step c opens stirring, is warming up to boiling, after keeping the temperature 2h-4h, is filtered and washes, obtain
To filter cake, filter cake is beaten to obtain slurries；
The obtained slurries of step d are warming up to 60-120 DEG C by e, and ammonium hydroxide is added, and adjust pH to 5.0-8.0, and observation slurries form molten
Gluey state keeps the temperature 2-6h, after being dehydrated to colloidal sol, is put into 400 DEG C of -600 DEG C of calcinings in Muffle furnace, obtains graininess titanium white
Powder；
F the graininess titanium dioxide that step e is obtained is crushed after to get the unordered meso-porous nano titanium dioxide with cyclic structure
Titanium.
2. the preparation method of unordered mesohole nano-titanium dioxide according to claim 1, it is characterised in that: in step a
Acidolysis titanium liquid, wherein TiO2Concentration be 180g/L-210g/L；Ti3+Concentration be 0.7-2.7g/L；Fe2+With the quality of TiO2
Than for 0.25-0.35；F value is 1.55-2.00；Specific gravity is 1.521-1.552g/cm3。
3. the preparation method of unordered mesohole nano-titanium dioxide according to claim 1, it is characterised in that: hydrogen in step a
Sodium oxide molybdena mass concentration is 8%-16%.
4. the preparation method of unordered mesohole nano-titanium dioxide according to claim 3, it is characterised in that: hydrogen in step a
The total volume ratio of sodium hydroxide solution and acidolysis titanium liquid is 100:300~200:300.
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| CN106830069A (en) * | 2017-02-15 | 2017-06-13 | 齐鲁工业大学 | A kind of flower-shaped mesoporous TiO 2 hierarchy and preparation method thereof |
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2018
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Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1348430A (en) * | 1999-04-23 | 2002-05-08 | 内诺株式会社 | Method for manufacturing photocatalytic titanium dioxide powder |
| CN1490249A (en) * | 2002-10-15 | 2004-04-21 | 北京化工大学 | Preparing method for nano titanium dioxide |
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