CN1146976A

CN1146976A - Process for preparing nm. titania

Info

Publication number: CN1146976A
Application number: CN 96117100
Authority: CN
Inventors: 程黎放; 张怡; 储昭琴; 田兴友; 胡智学; 张立德
Original assignee: INST OF SOLID PHYSICS CHINESE
Current assignee: INST OF SOLID PHYSICS CHINESE
Priority date: 1996-09-18
Filing date: 1996-09-18
Publication date: 1997-04-09
Anticipated expiration: 2016-09-18
Also published as: CN1044463C

Abstract

A process for preparing rutile-type and anatase-type nm. TiO2 powder from H2TiO3 comprises washing, purifying, dispersion emulsifying, drying, heat treatment and pulverization, and features easily available and cheap raw material, simple process, no corrosion, high safety, no pollution and high quality and purity (99%) of product.

Description

The manufacture method of nano titanium oxide

The present invention relates to the manufacture method of nano titanium dioxide powder.

Nano titanium oxide (TiO ₂), because of its particle ultra-fine, the surfactivity height, specific surface area is big, excellent properties such as good ultraviolet-absorbing and photocatalytic activity, in a lot of fields, as fine ceramics, high-grade paint, there is utmost point purposes widely sun care preparations, photocatalyst, chemical catalysis agent carrier, photochromics and chemical fibre delustring or the like aspect.

External general adopt titanium alkoxide liquid phase or gas phase hydrolysis method, titanium tetrachloride high-temperature oxidation or special hydrolysis method, (the titanium material compound is respectively Ti (OR) to titanyl sulfate liquid phase sol method ₄TiCl ₄TiOSO ₄) etc. method carried out nano-TiO ₂Preparation research, and realized suitability for industrialized production.More domestic units are also at the development nano-TiO ₂, all be to adopt the above-mentioned external method of usefulness basically, but because the main raw material overwhelming majority adopts Ti (OR) ₄And TiCl ₄, and Ti (OR) ₄Cost an arm and a leg, make main raw material TiO with it ₂Yield has only about 23%, therefore produces the 1Kg nano-TiO ₂Powder, raw materials cost valency just are higher than 500 yuan.TiCl ₄Also more expensive, when adopting hydrolysis method,,, and produce the equipment of required high-temperature corrosion resistance in batches to equipment corrosion, serious to topsoil with producing a large amount of HCl gas, one-time investment is big.

The object of the invention provides a kind of existing TiO of making that is different from ₂The method of nano powder, this method technological process is simple, and cost is low, constant product quality, the TiO for preparing ₂Nano powder purity height.

Manufacture method flow process of the present invention is as follows:

1. choosing of main raw material---2. washing purifying---3. dispersion and emulsion---

4. drying---5. thermal treatment---is 6. pulverized

1. choosing of main raw material: the present invention selects wet metatitanic acid (H for use ₂TiO ₃) be main raw material, cheap and easy to get, just about 8 yuan of per kilograms, preparation A phase anatase type TiO ₂To use A type metatitanic acid; Preparation R phase rutile type TiO ₂To use R type metatitanic acid.

2. washing purifying: in wet metatitanic acid, add volatile salt (NH ₄) ₂CO ₃, make the SO of chemisorption ₃Desorption and neutralization are acid, repeatedly wash and remove SO ₄ ^2-, obtain the wet H of purifying of neutrality or slightly inclined to one side alkali ₂TiO ₃

3. dispersion and emulsion: for fear of the wet H of purifying ₂TiO ₃Hard aggregation takes place in particulate in dry removal process subsequently, the present invention adopts polymeric surface active agent such as polyoxyethylene glycol (H[OCH ₂CH ₂] _nOH adds the wet H of purifying as dispersion agent ₂TiO ₃H is worked as in middle making beating ₂TiO ₃The polyoxyethylene glycol macromole of particle surface absorption some amount forms the colloid protective layer, will hinder drawing close of micelle, reduces the force of cohesion between the particle, reduces the intensity of coacervate.

As preparing rutile TiO ₂, then need add compound modifying agent.

4. dry: the exsiccant purpose is in order to remove mechanical water, because the H after disperseing ₂TiO ₃Contain about 80% moisture content in the slurry.

Dry available spraying drying, also available decompression cryodrying.

5. thermal treatment: purpose is in order to remove chemically-bonded water, to make H ₂TiO ₃→ TiO ₂Make the polymeric surface active agent combustion decomposition become CO ₂Crystal formation is transformed.Because remove the TiO of chemically-bonded water ₂Particle is unformed (amorphous), must handle the TiO that just can obtain A phase or R phase through comparatively high temps ₂

Preparation A phase anatase type TiO ₂400～500 ℃ of thermal treatment temps, time 1.5～3h obtains 15～20nmA phase TiO ₂, white powder; Preparation R phase nano rutile-type TiO ₂, 700～800 ℃ of time 1.5～3h of thermal treatment temp obtain the R phase TiO of 80～100nm ₂Raw white toner end.

5. pulverize: R phase TiO ₂Rutile-type, because of high-temperature calcination meeting generation granule interior densification, the essay grain annexs grows up, and apparent density increases, and therefore, by mechanical crushing method such as ball milling, gas-liquid is pulverized and is made it revert to primary particle.

The used wet metatitanic acid of the inventive method is given money as a gift in 100%, and the consumption that adds volatile salt is 3～8%, and the polymeric surface active agent consumption is 1～5%.

The TiO of the present invention's preparation ₂The key technical indexes of nano powder:

Crystalline phase	Purity	Outward appearance	Particle diameter	Specific surface	??PH	Surface properties
Crystalline phase	Purity	Outward appearance	Particle diameter	Specific surface	??PH	Surface properties	Anatase octahedrite	＞98.5％	The white powder	????～15nm	＞100 meters ²/ gram	???6～8	Wetting ability
Rutile	＞98.5％	This white powder	????～100nm	＞10 meters ²/ gram	???6～8	Wetting ability	Anatase octahedrite	＞98.5％	The white powder	????～15nm	＞100 meters ²/ gram	???6～8	Wetting ability

The advantage that the present invention gives prominence to is:

1. the main raw material metatitanic acid is cheap and easy to get, and nontoxicity does not have dangerous;

2. the manufacture craft process is simple and easy to control, is liquid phase reaction under the normal temperature and pressure, does not have corrosion, easily expands commercial scale production to;

3. waste gas, the pollution of waste water is minimum;

4. constant product quality, purity reach～and 99%;

5. prepare 1 kilogram of TiO ₂Nano powder, raw materials cost have only about 50 yuan, and this is than making TiO with the titanium alkoxide ₂The cost of nano powder is low ten times.

6. be convenient to transportation and storage.

Description of drawings;

Fig. 1 is a nano-TiO ₂(rutile phase) transmission electron microscope photo (* 4 ten thousand times);

Fig. 2 is a nano-TiO ₂(rutile phase) x ray diffration pattern x;

Fig. 3 is a nano-TiO ₂(anatase octahedrite phase) transmission electron microscope photo (* 10 ten thousand times);

Fig. 4 is a nano-TiO ₂(anatase octahedrite phase) x ray diffration pattern x.

Claims

1. a liquid phase method prepares the method for nano titanium oxide, it is characterized in that, selects wet metatitanic acid (H for use ₂TiO ₃) be main raw material, through the washing purifying, dispersion and emulsion, drying, thermal treatment, technological processs such as pulverizing are prepared the nanometer titanium dioxide titanium valve.

2. the method for claim 1 is characterized in that, adds volatile salt in wet metatitanic acid, repeatedly washs to obtain the wet H of purifying again ₂TiO ₃, add the wet H of purifying with polymeric surface active agent as dispersion agent again ₂TiO ₃, carry out drying treatment then, heat-treat again, 400～800 ℃ of thermal treatment temps, 1.5～3h pulverizes at last.

3. the method for claim 1 is characterized in that, prepare rutile TiO ₂, when dispersion and emulsion technology, also to add compound modifying agent.

4. the method for claim 1 is characterized in that, prepare A phase anatase type TiO ₂, 400～500 ℃ of thermal treatment temps, time 1.5～3h; Preparation R phase nano rutile-type TiO ₂, 700～800 ℃ of thermal treatment temps, time 1.5～3h.

5. the method for claim 1 is characterized in that, used wet metatitanic acid is given money as a gift in 100%, and the consumption for preparing used volatile salt is 3～8%, and the polymeric surface active agent consumption is 1～5%.

6. the method for claim 1 is characterized in that, preparation A phase anatase type TiO ₂, select A type metatitanic acid for use; Preparation R phase rutile type TiO ₂, select R type metatitanic acid for use.