JPS62153123A - Synthesis of antimonic acid - Google Patents

Abstract

PURPOSE:To produce vitreous antimonic acid, by hydroxylating antimony trioxide under a specific condition and carrying out wet-oxidization of the product in H2O2 to form antimony pentoxide. CONSTITUTION:A reactor furnished with a stirrer and a cooling jacket is charged with 250g of 35% aqueous solution of hydrogen peroxide, 250G of ion-exchange water and 250g of antimony trioxide and the content is thoroughly dispersed by stirring for 60min at 50+ or -20 deg.C. The slurry mixture is cooled, agitated and maintained at 20+ or -2 deg.C for >=24hr to effect hydroxylation reaction and obtain a pudding-like solid. The solid is transferred to a closed reactor furnished with a heater and oxidized at 120 deg.C under a gauge pressure of 1kg/cm<2> for 24hr. The oxidation product is dried at 100 deg.C for 24hr in a box-type hot-air dryer and pulverized in a mortar to obtain vitreous antimonic acid.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for synthesizing glassy antimonic acid-containing sulfur antimonic acid, and as one of its uses, it can be used as a solid electrolyte of an electrochromic display. It relates to a method for synthesizing products that exhibit excellent physical properties.

(Prior technology) Antimonic acid is used as an inorganic ion exchanger for selective adsorption of lithium ions (Li+), fuel cells that utilize proton conductivity, hydrogen separation membranes, solid electrolytes for chromic displays, etc. This is a material whose application is being considered.

This antimonic acid is also called hydrated antimony oxide.
For example, orthoantimonic acid (HsSbO4).

Metaantimony a (H5bO3), pyroantimonic acid.

Other names include nianantimony e (H4S bz Ot )-triantimonic acid (HsS b s O+). Among them, those dried at 50'C are 5b20s/4H.
Approximately 20, one atom of antimony has one hydroxyl group and one
It was found that there were 8 free waters, and X-ray diffraction showed that they were crystalline! + (H3Sb305(OH)
s) )3 (I(,Sb,06(OH) +s), which is the unit cell.

S is known to have 14 exchangeable hydrogen atoms, exhibits good proton conductivity, and has a temperature of 20°C.
It is also known that CM has values such as o and oxohmm. The water binds to the surface and pores, and the amount b
′-Adhesive water that changes depending on the preparation method.

There is bound water, which is bound to the parent material through hydrogen bonds, and what is called structural water, and the strength of these bonds changes continuously.
Igi, dried at 100℃ is 5b20.・2H20
The composition is close to that of

The above compound is hydrated antimony pentoxide, but when speaking of antimonic acid, there is also hydrated antimony trioxide 6''-, orthoantimonite (H3Sb03 or 5bzOs・OtH20), pyroantimonite. (H4
S b t Os or 5bfi03.2H20) metaantimonite (H2S b 204 or 5bt
Os・H20), etc. are known.

Similar to hydrated antimony pentoxide, the strength of the water bond in this hydrated antimony trioxide changes continuously. In addition to antimony pentoxide and antimony trioxide, antimony oxides such as antimony tetroxide (Sb204) and intermediate oxide (Sb60H) are known, and the presence of hydrated products of these is also possible.

The above antimonic acid (hydrous antimony oxide) is amorphous with different shapes S and X-ray diffraction patterns.

Glassy? It is known that there are three types of states: The synthesis of these three types of antimonic acids was carried out by Abe et al.
4). The method is shown as a).

(a) Amorphous antimonic acid can be obtained by first hydrolyzing 3 o rnl of antimony pentachloride with the same volume of water to create a concentrated solution, then hydrolyzing the concentrated solution with 2 tablespoons of water, and dissolving the resulting precipitate into 20 ml of precipitate. Age for 4 hours at ~25°C. Crack the precipitate, wash it with pure water at 5℃ using a centrifuge (10,000 rpm) until no chlorine ions are observed, and then wash it for about 1 hour.
It has been air-dried for years.

Similar to amorphous antimonic acid, crystalline antimonic acid is hydrolyzed and aged at 50° C. for 20 days to crystallize it.

After washing with water, the same treatment as for the amorphous material is performed.

Glassy antimonic acid is obtained by quickly dissolving wet, water-washed amorphous antimonic acid in warm water at 80°C, pouring it thinly into a Petri dish, drying it as quickly as possible using an electric fan, and then air-drying it for one year.

The X-ray diffraction patterns of the above three types of antimonic acids are reported as shown in Figure 1.

As shown in Figure 1, crystalline antimonic acid has a diffraction angle of 14
．． 8°, 28.0°, 29.8°, 49.2°, 5th,
Glassy antimonic acid has a peak of 275'
has a peak at Moreover, amorphous (amorphous) does not show a peak.

In addition to this method, antimonic acid can be synthesized by ion-exchanging potassium hexahydroxyantimonate (Oki) (L, H, Baetsle et al., J (no.
rg, Nucl, chem, -639 → Method of treating antimony sulfide with fuming nitric acid (C, J, Vil
al 1ans et al. Amer, Mineralo-gis
t, 37 982 (1952))) has been reported in which antimony trioxide is wet oxidized in hydrogen peroxide, washed with water, and dried (Obama et al., Journal of the Chemical Society of Japan, 5488 (1985)).

(Problems to be solved by the invention) Among the conventional methods for synthesizing antimonic acid as described above,
The three standard methods of synthesizing antimonic acid reported by Abe et al. are all laboratory methods in which the product is air-dried for years, which is unrealistic as an industrial method, so they cannot be used. do not have. Moreover, the second and third methods are also unsuitable because impurities such as chlorine ions (Ca) and potassium ions (K+) are likely to be mixed in, and above all, only crystalline antimonic acid can be obtained.

One more thing left. The method of wet oxidation of antimony dioxide with hydrogen peroxide is antimonic acid that does not contain impurities such as CA-Gin + (water-containing antimony pentoxide).
It is convenient because you can get Unfortunately, however, this method only yields highly crystalline antimonic acid.

(Object of the Invention) The present invention provides a novel means for industrially synthesizing antimonic acid containing glassy antimonic acid based on one or more of the prior art techniques. Another object of the present invention is to demonstrate that antimonic acid synthesized according to the present invention exhibits excellent physical properties when used as a main component of a solid electrolyte layer of an electrochromic display device.

(Structure of the Invention) That is, 1. The present invention includes a method for wet-oxidizing antimony trioxide in hydrogen peroxide water to produce water-containing antimony pentoxide (antimonic acid). This is a method for synthesizing antimonic acid containing glassy antimonic acid, which is characterized in that an odorization reaction is carried out at a temperature of 22° C. or lower for 24 hours or more, and then wet oxidation is carried out.

(Detailed description of the invention) For the olization reaction, which is carried out as a pre-reaction for wet oxidation, hydrogen peroxide solution is added to antimony trioxide and stirred for a long time.
It is a process of ripening, and refers to a reaction that produces an OH-bridged all complex from a hydroxy complex. When the reaction has proceeded sufficiently, a pudding-like solid is obtained, and by wet oxidation of this, glassy antimonic acid is obtained.

However, the frequency with which glassy antimonic acid is obtained is related to the temperature during the olization reaction, and specifically, it is preferable to set the temperature to 22°C or less.

The olization reaction of antimony trioxide is an exothermic reaction.1 In normal conditions, the temperature rises to 60°C or more.
In the present invention, the reaction vessel must be cooled and kept warm from the outside. In addition, it is recommended that the olization reaction be carried out for 24 hours or more to ensure sufficient ripening, and the upper limit (i is not particularly specified, but for example 100
It is okay if it takes about an hour or more.

In addition, wet oxidation is a process in which hydrogen peroxide and water are heated to 70 to 150°C for oxidation, and if hydrogen peroxide is added during the olization reaction,
It is practical to use this directly as an oxidizing agent.

Furthermore, the wet oxidation is preferably carried out at a pressure of 1.5 atmospheres or more, and by carrying out the reaction under pressure, the oil absorption value of the obtained antimonic acid can be reduced to, for example, 25 or less.

As a supplementary explanation, antimonic acid (in powder form) with low oil absorption means that it is solidified in a layered form with a small amount of resin binder, and when this antimonic acid is used in the solid electrolyte layer of an electrochromic display device, Resin binder b' which is a factor that hinders proton conductivity
-Because there aren't many.

A good result of high proton conductivity is obtained.

Such a preferable oil absorption value is 25 or less.

FIG. 2 shows X-ray diffraction patterns of antimonic acid obtained in Comparative Example S and Examples described later. Among these, antimonic acid B, antimonic acid C, ie.

According to the present invention, antimonic acid having a peak at a diffraction angle of 27.3°, which indicates the presence of glassy antimonic acid, can be obtained.

This is a synthesis method that produces a mixture of glassy antimonic acid and crystalline amtrimonic acid. The peak at 27.5° is dependent on the temperature of the olization reaction, and as the temperature rises in the reactor, the peak at 27.3° in the X-ray diffraction pattern, which indicates glassiness, becomes slightly smaller or disappears. . Antimony eA is an X-ray diffraction pattern of a substance consisting only of crystalline antimonic acid.

Examples of the present invention will be described below along with comparative examples.

[Comparative example]

In a reactor equipped with a stirrer and a cooling jacket, add 250 g of 55% hydrogen peroxide and 250 g of ion-exchanged water.

Add 250 g of antimony trioxide and disperse well while stirring at 50±2°C for 60 minutes. Subsequently, the mixed slurry liquid was cooled and stirred, and the olization reaction was continued for more than 24 hours while maintaining the temperature at 60±2°C, to obtain a pudding-like solid.

The solid material was transferred to a sealed reactor equipped with a heater, and oxidized at 120°C and a cage pressure of 1ky/ff1 (the internal pressure inside the reactor was 2 atm) for 24 hours. After drying at 100°C for 24 hours, it was milled in a mortar and subjected to X-ray diffraction analysis and oil absorption measurements, and a diffraction pattern similar to that of antimonic acid A shown in Figure 2 was obtained, with an oil absorption of 22
．． It was 0.

In addition, the olization reaction product solid was transferred to a separable flask with a reflux device, and heated to 100°C in a water path at normal pressure.
After 4 hours of oxidation reaction, it was dried in a hot air dryer at 100°C for 24 hours, and ground in a mortar. X-ray diffraction analysis and oil absorption measurements showed that a diffraction pattern similar to that of antimonic acid A shown in Figure 2 was obtained. , the oil absorption amount was 35.0.

[Example 1] In a reactor equipped with a stirrer and a cooling jacket, 35% hydrogen peroxide solution was added at 250.9%. Add 250.9° of ion-exchanged water and 250 g of antimony trioxide, and disperse well with stirring at 2° C. for 60 minutes in 50 parts.

Subsequently, the mixed slurry liquid was cooled and stirred, and the olization reaction was continued for more than 24 hours while maintaining 20 parts at 2 ° C.
A pudding-like solid was obtained.

Transfer the solid to a closed reactor equipped with a heater and heat to 12 o'd.

Gauge pressure 1kg/cr! (The internal pressure of the reactor is 2 atm) and 2
Oxidation reaction was carried out for 4 hours, and the product was dried at 100° in a box-type hot air dryer.
C. After drying for 24 hours, it was milled in a mortar and subjected to X-ray diffraction analysis and oil absorption measurement. A diffraction pattern similar to that of antimonic acid B shown in FIG. 2 was obtained, and the oil absorption amount was 21.0.

[Example 2] In the reactor of Example 1, 2,509 people each of 35% hydrogen peroxide, ion-exchanged water, and antimony trioxide were well dispersed at 50 ± 2°C, then cooled, and 10 parts were kept at 2°C. While 36
When the olization reaction was continued for more than an hour, a pudding-like solid was obtained.

The oxidation reaction was carried out at 120°C and a gauge pressure of 1 kg/7 for 24 hours, and the product was dried at 100°C for 24 hours and then milled.

X-ray diffraction analysis and oil absorption measurements.

A diffraction pattern similar to that of antimonic acid C shown in FIG. 2 was obtained, and the oil absorption was 20.0.

[Use of invention]

The explanatory diagram of the cross section and usage cap of one embodiment of the electrochromic display using antimonic acid of the present invention is shown in the sixth figure.
As shown in the figure.

The electrochromic display body according to the present invention has a patterned transparent electrode (2) on one side of a glass transparent substrate (1), and one display part has an electrochromic body IJ t31.
, an insulating layer (4) in the display area and a negative pattern, a solid electrolyte layer (5) made of antimonic acid of the present invention on almost the entire upper surface, a reversible oxide layer +6+ on the upper part, and a concentrated layer on the upper part. Eight patterned transparent electrodes (2) in the shape of successively laminating an electric layer (7) and a protective layer (8).
By applying an exchange voltage between the current collector layer (7) and the current collector layer (7), coloring and fading is achieved.

The stability of display materials using the vitreous antimonic acid obtained by the synthesis method of the present invention will be described below.

A transparent electrode (2) made of indium oxide and tin oxide is provided in a pattern on a glass substrate (1), and tungsten oxide (CWos) is applied to the display area on the transparent electrode (2), and screen printing is applied to the non-display area of the same layer. Toyo Ink Manufacturing 1 by law
Insulation created by printing with Shiki's product name 5S-25000 medium ink, '偕(4).

Furthermore, antimony a of B in the X-ray diffraction pattern shown in FIG. 2 is placed on top as a solid electrolyte.

and glycerin and water at a weight ratio of 5:1.65:0
．． A solid electrolyte layer with a film thickness of about 150 to 160 μm (5
), and on top of that, 10 parts of carbon-based conductive paste (manufactured by Moshoku Kasei 4, trade name: Dotite Xc-74) and 3 parts of Prussian blue added. A reversible oxidizing substance layer (6) is formed by screen printing, and a silver thread conductive paste (manufactured by Moshoku Kasei ■, product name: XA-167) is applied on top.
) was layered using a screen printing method to form a current collector layer (7), and then a protective layer (8) was formed on top by covering the entire surface with an epoxy resin-based hardening type light emitting diode using a screen printing method for protection. Layer 18).

The display body having the above configuration was stored at 70'C and the degree of deterioration of its response was observed in Fig. b'-4.

This figure shows the amount of electricity that flows for coloring when the display is returned to 25°C from 70°C and an IV voltage is applied for 1 second.As the display deteriorates, coloring becomes difficult and the amount of electricity decreases.

In this display, antimonic acid is compared with the antimonic acid shown in the X-ray diffraction pattern shown in Figure 2 (the 27.3° puck, which indicates glassiness, is not observed in this antimonic acid). The deterioration speed was 1/4 that of the original.

Furthermore, as a solid electrolyte, antimonic acid C1 in the X-ray diffraction pattern shown in FIG.
4,8°, 28.0°, 29.8°) was 28.5%.

The display with the above configuration was stored at 70°C and the degree of deterioration of its responsiveness was observed, and the deterioration rate was 1/20 compared to that using antimony dA with the X-ray diffraction pattern shown in Figure 2. Met.

Cells were formed using antimonic acid, which shows an X-ray diffraction pattern.
, 280°, 29.8°) to the average (horizontal axis) and the degree of deterioration of the response after storage at 70°C (vertical axis) is shown in Figure 5. As shown in the figure, it can be seen that the higher the peak intensity ratio, that is, the higher the glass content, the lower the degree of deterioration h''-.

From the above, it can be seen that antimonic acid containing glass is very effective for electrochromic displays.

(Effects of the Invention) The method for synthesizing vitreous antimonic acid of the present invention is as described above.

Although it was not possible to obtain glassy antimonic acid using industrial methods, this method succeeded in synthesizing glassy antimonic acid, although it was a mixture of crystalline and glassy substances. , and its technical knowledge is significant. Furthermore, if the antimonic acid of the present invention obtained in this manner at °C is used as the main component of the solid electrolyte layer of an electrochromic display, a remarkable improvement can be seen in the heat resistance and durability of the electrochromic display. , the practical cost is also high.

[Brief Description of the Drawings] Figure 1 is an explanatory diagram showing the X-ray diffraction pattern of each state of antimonic acid, and Figure 2 is an explanatory diagram showing the X-ray diffraction pattern of antimonic acid in each state. FIG. 5 is a graph showing an X-ray diffraction pattern of antimonic acid, FIG. 5 is an explanatory diagram showing an example of an electrochromic display, and FIG. It is a graph diagram showing virilization parasitism,
The figure shows the X-ray diffraction pattern of antimony/(di) according to the present invention.
The glassy peak intensity ratio and its antimony d'
f The temperature of the electrochromic display used was 70°C.
This is a graph showing the relationship between deterioration rate and deterioration rate. +11...Transparent substrate (2)...Transparent electrode (3)...Electrochromic body layer (4)...Insulating layer (5)...Solid electrolyte layer (6)...Reversible oxidizing substance Layer (7)... Current collector, Layer (8)...
protective layer

Claims (3)

[Claims] (1) In a method for synthesizing water-containing antimony pentoxide in which antimony trioxide is wet-oxidized in hydrogen peroxide, an olization reaction at a temperature of 22°C or less is performed for 24 hours or more as a pre-reaction to the wet oxidation, and then the wet oxidation A method for synthesizing antimonic acid containing glassy antimonic acid, which is characterized by carrying out oxidation. (2) The method for synthesizing antimonic acid according to claim 1, wherein the wet oxidation is carried out under pressure of 1.5 atmospheres or more. (3) The method for synthesizing antimonic acid according to claim 1 or 2, which yields antimonic acid having an oil absorption value of 25 or less.