CN1834018A

CN1834018A - Method of synthetizing superfine powder of aluminum titanate

Info

Publication number: CN1834018A
Application number: CN 200610005317
Authority: CN
Inventors: 江伟辉; 周健儿; 魏恒勇; 刘建军; 顾幸勇; 朱小平
Original assignee: Jingdezhen Ceramic Institute
Current assignee: Jingdezhen Ceramic Institute
Priority date: 2006-01-12
Filing date: 2006-01-12
Publication date: 2006-09-20
Anticipated expiration: 2026-01-12
Also published as: CN100339307C

Abstract

This invention discloses a method to synthesize superfine aluminium titanate powder. In this invention, titanium tetrachloride and aluminium nitrate as precursors, anhydrous low-carbon alcohol as solvent and glycol or/and PVA with a molecular weight of 600~10000 as dispersors, are mixed and fircely stirred into a mixed alcohol solution, which is then rapidly hydrolyzed at a temperature of 60~90 deg. C, polycondensed into a gel, dried, milled and calcined to obtain superfine aluminium titanate powder. In this invention, crystal water is utilized, which omits water addition and makes the hydrolysis easy to control. It has the advantages of simple technique, easy operation, low cost and short period, and is applicable in industrial production.

Description

A kind of method of synthetizing superfine powder of aluminum titanate

Technical field the present invention relates to the superfine powder technology of preparing, is specifically related to adopt the method for colloidal sol-gel process synthetizing superfine powder of aluminum titanate.

The background technology aluminum titanate ceramic material is a kind of elite clone that integrates high-melting-point, low bulk characteristics, and its fusing point is up to 1860 ℃, and the coefficient of expansion is 0.5～1.5 * 10 ^-6/ ℃, thereby have broad application prospects.At present, the method for preparing the aluminium titanates powder has chemical Vapor deposition process (CVD), solid phase method, coprecipitation method, sol-gel processing (sol-gel), pack, combustion method, organic polymer method and hydrothermal method etc.Solid phase method directly adopts aluminum oxide and titanium dioxide to prepare the aluminium titanates powder, and it is difficult to evenly mixed, and the synthesis temperature height.Combustion method and hydrothermal method are had relatively high expectations to equipment, prepare powder by liquid phase method and then have powder good uniformity, purity height, can accurately control advantages such as stoichiometric ratio.

Sol-gel processing is one of common method of the synthetic aluminium titanates powder of liquid phase method.Traditional technology is that the alkoxide of employing aluminium and titanium is a raw material mostly, adds water and makes it that hydrolysis, polycondensation take place in organic medium, forms gel, after gel drying, the calcination processing, obtains the aluminium titanates powder.Because the titanium hydrolysis of alkoxide is active high, need to reduce its hydrolysis rate, as adopt the dropping mode to introduce water, and perhaps use sequestrant and titanium alcohol salt formation inner complex, reduce its reactive behavior, realize and the same one-step hydrolysis of aluminium-alcohol salt, therefore, the gel required time is long, cause the production cycle long, cost is high, operational condition requires high, is difficult to realize large-scale industrial production.

Summary of the invention the object of the present invention is to provide a kind of method of synthetizing superfine powder of aluminum titanate, this method adopts low price raw material, need not to add water and just hydrolysis, polycondensation can take place, solved long, problem such as cost is high, reaction is wayward of prior synthesizing method cycle.

The present invention is with titanium tetrachloride (TiCl ₄) and aluminum nitrate (Al (NO ₃) ₃9H ₂O) be presoma, with the anhydrous low-carbon alcohol is solvent, or/and molecular weight is 600～10000 polyoxyethylene glycol is dispersion agent, forms alcohol mixture solution with glycerine under intense agitation, wherein: the total mole number of titanium tetrachloride and aluminum nitrate: the mole number of anhydrous low-carbon alcohol=1: 10～25, TiCl ₄: Al (NO ₃) ₃9H ₂O=1: 2 (mol ratios); Under 60～90 ℃ condition, utilize the contained crystal water of aluminum nitrate itself to make alcohol mixture solution that quick hydrolysis, polycondensation formation gel take place then, obtain superfine powder of aluminum titanate after drying, grinding, the calcination processing.

Described anhydrous low-carbon alcohol can be one or more a mixture of methyl alcohol, ethanol, propyl alcohol, Virahol, propyl carbinol;

Described dispersion agent add-on preferably accounts for 0.5～3% of alcohol mixture total solution weight;

The optimum temperature range of described drying treatment is 60～85 ℃, and the optimum temperature range of calcination processing is 1320～1380 ℃, and soaking time is 30～60min.

The present invention has directly utilized contained crystal water in the aluminum nitrate, has not only saved and has added the water step, and the more important thing is that the hydrolysis reaction of the crystal water that discharges in the aluminum nitrate and titanium tetrachloride alcoholic solution is easy to control, can be by the conversion rate of heating regulation and control colloidal sol to gel.The present invention both need not to add sequestrant, also need not to introduce catalyzer, compared the shortening of gel cycle with traditional sol-gel method more than 40%, and cost reduces more than 50%.

Description of drawings

Fig. 1 is the XRD figure spectrum of embodiment 1 powder;

Fig. 2 is the TEM photo of embodiment 1 powder;

Fig. 3 is the XRD figure spectrum of embodiment 2 powders;

Fig. 4 is the TEM photo of embodiment 2 powders;

Fig. 5 is the XRD figure spectrum of embodiment 3 powders;

Fig. 6 is the SEM photo of embodiment 3 powders;

Fig. 7 is the XRD figure spectrum of embodiment 4 powders;

Fig. 8 is the SEM photo of embodiment 4 powders;

Fig. 9 is a process flow sheet of the present invention.

Embodiment

Embodiment 1

With 0.036molAl (NO ₃) ₃9H ₂O (analytical pure), 0.018molTiCl ₄The precursor material of (chemical pure), be dissolved in 0.735mol dehydrated alcohol (analytical pure), obtain the alcohol mixture solution A of titanium tetrachloride and aluminum nitrate, under vigorous stirring, 1.5wt% glycerine (analytical pure) is added wherein, obtain mixed liquid B, be placed in 80 ℃ the water-bath and heat, reflux, make it to take place hydrolysis condensation reaction, form gel C, then through 65 ℃ of dry xerogel D that form, put into crucible after the grinding, calcine in electric furnace: temperature rise rate is 4 ℃/min before 400 ℃, rises to 1350 ℃ with 10 ℃/min then, insulation 0.5h can obtain the superfine powder of aluminum titanate body.The XRD analysis of product shows that institute's synthetic powder is the aluminium titanates (see figure 1); TEM photo among Fig. 2 shows, powder dispersity is good, particle diameter is less than 1 μ m.

Embodiment 2

Change dehydrated alcohol (analytical pure) consumption among the embodiment 1 into 1.080mol, water bath reflux temperature changes 65 ℃ into, other condition is constant, obtain the aluminium titanates powder, confirm that through XRD analysis the gained powder is the aluminium titanates (see figure 3), from the TEM photo of Fig. 4 as can be seen, powder dispersity is good, and median size is less than 1 μ m.

Embodiment 3

Change dehydrated alcohol (analytical pure) among the embodiment 1 into anhydrous isopropyl alcohol (analytical pure), other condition is constant, and resultant powder is an aluminium titanates crystalline phase (see figure 5) through XRD analysis, and sem analysis shows that the aluminium titanates powder dispersity is good, the even (see figure 6) of size distribution.

Embodiment 4

Changing 1.5wt% dispersion agent glycerine (analytical pure) among the embodiment 1 into 1.5wt% Macrogol 4000 (analytical pure) adds simultaneously with 1.5wt% dispersion agent glycerine (analytical pure), other condition is constant, obtain aluminium titanates powder (seeing Fig. 7 XRD analysis result), SEM photo explanation among Fig. 8, institute's synthetic aluminium titanates powder crystal grain is tiny, is evenly distributed.

Claims

1, a kind of method of synthetizing superfine powder of aluminum titanate is characterized in that with titanium tetrachloride (TiCl ₄) and aluminum nitrate (Al (NO ₃) ₃9H ₂O) be presoma, with the anhydrous low-carbon alcohol is solvent, or/and molecular weight is 600～10000 polyoxyethylene glycol is dispersion agent, forms alcohol mixture solution with glycerine under intense agitation, wherein: the total mole number of titanium tetrachloride and aluminum nitrate: the mole number of anhydrous low-carbon alcohol=1: 10～25, TiCl ₄: Al (NO ₃) ₃9H ₂O=1: 2 (mol ratios); Under 60～90 ℃ condition, utilize the contained crystal water of aluminum nitrate itself to make alcohol mixture solution that quick hydrolysis, polycondensation formation gel take place then, obtain superfine powder of aluminum titanate after drying, grinding, the calcination processing.

2, the method for synthetizing superfine powder of aluminum titanate according to claim 1 is characterized in that described anhydrous low-carbon alcohol is one or more a mixture of methyl alcohol, ethanol, propyl alcohol, Virahol, propyl carbinol.

3, the method for synthetizing superfine powder of aluminum titanate according to claim 1 is characterized in that described dispersion agent add-on accounts for 0.5～3% of alcohol mixture total solution weight.

4, the method for synthetizing superfine powder of aluminum titanate according to claim 1, the temperature that it is characterized in that described drying treatment are 60～85 ℃, and the temperature of calcination processing is 1320～1380 ℃, and soaking time is 30～60min.