JP2545726B2 - Method for producing metal sulfide from metal alkoxide - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a metal sulfide from a metal alkoxide, which has recently been used in various fields such as fluorescence, phosphorescence, semiconductivity and infrared light transmission. Depending on its properties, it is widely used in the electronic field such as fluorescent materials, phosphorescent materials, photoelectric devices, infrared detectors, infrared optical fibers, and also widely used as pigments including cadmium yellow. The present invention mainly relates to a method for producing a metal sulfide used for them.

[0002]

2. Description of the Related Art Conventionally, metal sulfides have been produced by (1) a method of generating hydrogen sulfide in an aqueous solution of a metal salt, or (2) a method of heating metal and sulfur or a compound thereof. . For example, in the case of titanium sulfide, the method of reacting titanium chloride and hydrogen sulfide with heat is hot, and with aluminum sulfide, the method of mixing aluminum and sulfur into fine powder, and applying pressure to ignite the powder is also For zirconium sulfide, a method is known in which zirconium sulfide is formed on a tungsten wire heated with steam of zirconium chloride and sulfur.

[0003]

In the production of metal sulfide according to the prior art, the method (1) cannot synthesize a sulfide to be hydrolyzed, and the PH at the time of precipitation differs depending on the metal. There is a drawback that mixing of multiple metal elements cannot be performed at the atomic level. In addition, the method (2) generally requires heating at about 1000 ° C., and therefore cannot be easily manufactured. In addition, these methods also have a problem that sulfides cannot be obtained in the form of fine powders, and fine sulfide powders cannot be easily produced.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above problems, and in the production of a metal sulfide from a metal alkoxide, a metal produced by being dissolved in alcohol or alcohol and toluene under reflux with stirring. This is a method for producing a metal sulfide by flowing or bubbling hydrogen sulfide gas into a non-aqueous solution of alkoxide at a temperature under reflux to produce a metal sulfide, and separating a solvent from the product. That is, the present invention enables the synthesis of sulfide by utilizing a non-aqueous metal alkoxide solution using a non-aqueous solvent such as toluene or alcohol in place of the aqueous solution of a metal salt, and the reaction in the non-aqueous solvent. Therefore, PH at the time of precipitation
It enabled the formation of a precipitate independent of the temperature. Further, it becomes possible to separate the solvent from the precipitation product at a lower temperature than in the conventional case, and a fine powder with less aggregation can be obtained. In the present invention, the reaction between the non-aqueous solution of the metal alkoxide and the hydrogen sulfide gas is carried out by flowing or bubbling the hydrogen sulfide gas at a temperature under reflux, and the separation of the solvent from the product obtained by the reaction. Then, the metal sulfide is obtained by removing the precipitate by desolvation, for example, centrifugation, and drying it, preferably by vacuum drying. The reaction between the non-aqueous solution of the metal alkoxide and the hydrogen sulfide gas at the temperature under reflux cannot be carried out industrially because the reaction is slow at low temperature, and the reaction in the non-aqueous solution is not recommended. It cannot be carried out at higher temperatures. Further, as the metal alkoxide, a single metal alkoxide or a plurality of metal alkoxides can be used.

[0005]

The metal alkoxide is hydrolyzed by reacting with water or a mixture of water and alcohol to form a precipitate of ceramic precursors, that is, oxides, hydroxides and hydrates. In this reaction, very fine ceramic particles are obtained. If the deposited precipitate is an oxide, it can be dried as it is to give a hydroxide,
In the case of a hydrate, it can be made into fine ceramic particles by calcining. However, when obtaining a metal sulfide, there were the above-mentioned problems. Therefore, it was clarified that sulfide can be produced by the reaction of a non-aqueous metal alkoxide solution and hydrogen sulfide gas from the idea that hydrogen sulfide in which oxygen of water is replaced with sulfur of the same group easily reacts with hydrogen sulfide to produce sulfide. The invention has been completed.
Further, as a starting material, a metal alkoxide produced by dissolving alcohol or alcohol and toluene under stirring and reflux is used, and fine metal sulfide particles are obtained.

That is, in general, when the metal element is represented by M, the reaction between the metal alkoxide and hydrogen sulfide is sulfur S in the compound.
When the valence of is considered to be -2, it can be expressed as follows. For divalent metal M (OR) ₂ + H ₂ S → MS + 2 ROH (M = Zn,
Cd, Mn, etc.) 2M (OR) ₃ + 3H ₂ S → M ₂ S ₃ + 6ROH (M
= Rare earths such as As and La) For a tetravalent metal M (OR) ₄ + 2H ₂ S → MS ₂ + 4ROH (M = S
Sulfur (n, Mn, Co, etc.) often forms not only S- ² but also a strongly covalent bond in the compound, and in this case, it is formulated only from the ionic balance as described above. Although not possible for some, the above reaction is general.
In a sulfide composed of two kinds of divalent metals M and M ′, M (OR) ₂ + M ′ (OR) ₂ + H ₂ S → (M _1/2 M
There are many reactions of _½ ) S + 2ROH.

[0007]

Example 1 3.6148 g of metal barium was washed with methanol to remove surface oxides. This was further passed through benzene and then dissolved in 200 ml of ethanol under stirring and reflux to obtain an ethanol solution of barium ethoxide. Hydrogen sulfide gas was bubbled while stirring the solution under reflux. The formed precipitate was barium sulfide BaS as identified by powder X-ray diffraction.

[0008]

Example 2 8.0661 g of lead acetate trihydrate was dissolved in a mixed solvent of 50 ml of ethanol and 300 ml of toluene,
Azeotropic dehydration was performed. Separately, barium 2.9258g
Was dissolved in 250 ml of ethanol and stirred under reflux for 2 hours.
An ethanol solution of barium ethoxide was used. This solution was added to the above lead acetate trihydrate, stirred and refluxed for 2 hours, cooled to room temperature, and centrifuged to separate the precipitated barium acetate and lead ethoxide solution. Hydrogen sulfide gas was bubbled while stirring the obtained lead ethoxide solution under reflux. The produced precipitate was lead sulfide PbS as identified by powder X-ray diffraction.

[0009]

Example 3 7.0006 g of manganese chloride tetrahydrate was dissolved in 400 ml of ethanol and azeotropically dehydrated with toluene. 1.6389 g of sodium in this solution
Was added, and the mixture was stirred and refluxed for 2 hours, cooled to room temperature, and centrifuged to separate the obtained manganese ethoxide solution from the by-product sodium chloride. Hydrogen sulfide gas was bubbled while stirring the obtained manganese ethoxide solution under reflux. The formed precipitate was manganese sulfide MnS as identified by powder X-ray diffraction.

[0010]

Example 4 Anhydrous niobium pentachloride (5.2612 g) was dissolved in a mixed solvent of 200 ml of ethanol and 150 ml of toluene, and ammonia gas was bubbled while cooling with ice, followed by centrifugation to produce a niobium ethoxide solution and a by-product. The product ammonium chloride was separated. Also, barium 1.
5346 g was dissolved in 100 ml of ethanol with stirring under reflux to obtain an ethanol solution of barium ethoxide.
The concentration of the obtained niobium ethoxide solution was determined by the gravimetric method.
Calculated from the weight of barium using the concentration of barium ethoxide and the amount of ethanol as a solvent, 250 ml of a mixed solution in which the molar ratio of both was 1: 1 was prepared, and hydrogen sulfide gas was bubbled while stirring this under reflux. The produced precipitate was amorphous when subjected to powder X-ray diffraction.

[0011]

Example 5 Table 1 including the cases of Examples 1-4 described above
And shown in Table 2. Table 1 shows the synthesis of single metal sulfide and the synthesis of the following metals. Y, Ba, Sr, Mg, C
a, Pb, Zn, Mn, Fe, Co, Sn, and an alkoxide solution of each metal were synthesized, and hydrogen sulfide gas was flowed under reflux. Thereafter, the precipitate was taken out by centrifugation and vacuum dried to obtain a powder. The results of the powder X-ray diffraction are shown. Table 2 shows the synthesis of sulfides composed of two metals, Ba and Ti, Sr and Ti, Ba and Sr, Ba and S.
It carried out about the system of n, Ba, and Nb. Hydrogen sulfide gas was flowed under reflux to a solution prepared by synthesizing each alkoxide and adjusting the metal to be equimolar. Thereafter, the precipitate was taken out by centrifugation and vacuum dried to obtain a powder. The results of the powder X-ray diffraction are shown.

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

As described above in detail, according to the present invention, the metal sulfide to be hydrolyzed can be produced from the metal alkoxide produced by dissolving it in alcohol or alcohol and toluene under stirring and reflux. It is also possible to produce a mixed sulfide of a plurality of metal elements, and it is possible to produce a fine powder of a metal sulfide. Further, according to the present invention, it becomes possible to produce a fine powder of a metal sulfide used in the chemical industry and the like. As described above, the present invention has industrial value.

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Claims (2)

(57) [Claims] 1. In the production of a metal sulfide from a metal alkoxide, hydrogen sulfide gas is flowed or bubbled at a temperature under reflux in a non-aqueous solution of a metal alkoxide produced by dissolving alcohol or alcohol and toluene in an alcohol under stirring with reflux. A method for producing a metal sulfide by producing a metal sulfide and separating a solvent from the product. 2. The method for producing a metal sulfide according to claim 1, wherein a single or a plurality of metal alkoxides are used as the metal alkoxide.