KR20140076645A

KR20140076645A - Particulate composition containing nitrate salt, method for producing same, glass, and method for storing nitrate salt

Info

Publication number: KR20140076645A
Application number: KR20147014862A
Authority: KR
Inventors: 히로노부 오가타; 히로타카 하야시; 나오키 마츠모토
Original assignee: 사카이 가가쿠 고교 가부시키가이샤
Priority date: 2012-08-16
Filing date: 2013-08-09
Publication date: 2014-06-20
Also published as: KR101522151B1; JP2014185076A; TWI594949B; KR20140129253A; TW201414676A; JP5660170B2; JP5692831B2; JP5692832B2; CN104053629B; CN104053629A; JP2014055098A; KR101822704B1; WO2014027617A1; JP2014177397A

Abstract

One of the objects of the present invention is to provide a material containing strontium nitrate or barium nitrate which is high in safety and easy to handle and which is highly safe in suppressing the potential danger of oxidative power and sensitivity to impact, And to provide a material containing barium nitrate. The particulate composition of the present invention contains strontium nitrate and / or barium nitrate and hydrophobic silica. The method for producing the particulate composition of the present invention includes a step of mixing strontium nitrate and / or barium nitrate with hydrophobic silica.

Description

TECHNICAL FIELD [0001] The present invention relates to a particulate composition containing a nitrate, a method for producing the same, a method for preserving the same, and a method for preserving a nitrate salt.

The present invention relates to a particulate composition containing nitrate, a process for producing the same, a glass formed from the particulate composition, and a method for preserving nitrate.

Strontium nitrate or barium nitrate are used as raw materials for gunpowder and foot paints. Strontium nitrate is also used as a gas generating agent for an airbag of an automobile (for example, Patent Document 1).

Strontium nitrate or barium nitrate may oxidize flammable materials and cause severe combustion or explosion. In accordance with the United Nations Recommendation on the TRANSPORT OF DANGEROUS GOODS - Manual of Tests and Criteria - Third revised edition, In the combustion test of CLASS 5-Division 5.1 (oxidizing solid) according to the recommendation, it is a substance corresponding to dangerous goods. Such dangerous materials expose workers who deal with them to danger, and there is a problem of safety. When handling in a factory or the like, it is necessary to install an explosion-proof or explosion-proof equipment in order to secure safety, which is strictly restricted in terms of transportation and storage, and is disadvantageous in terms of cost.

In addition, strontium nitrate or barium nitrate is not limited to explosive use but is also expected as a raw material for ceramics and glass. When it is used as a raw material for ceramics or glass, its oxidizing property may cause safety in molding and handling. As described above, raw materials for ceramics and glass are required to be modified to a material with higher safety, which eliminates the risk.

Up to now, as a method for modifying strontium nitrate or barium nitrate, a method of preventing the solidification of particles by containing an appropriate amount of fine particle silicic acid has been disclosed (Patent Document 2). However, general particulate silicic acid is insufficient to reduce the risk of explosion or combustion.

As a conventional method for reducing the risk of explosion or combustion, there is a method of adding alkyl benzene sulfonic acid. Alkylbenzenesulfonic acid, a surfactant, is used as a synthetic detergent for household and business use (for washing and kitchen use) and also as a dyeing aid, an agrochemical emulsifying agent, a scouring agent, a dispersing agent and a cosmetic product. On the other hand, there are problems such as foaming in rivers and sewage treatment plants and low biodegradability compared with other general surfactants, and therefore it is not suitable as an additive when considering industrial wastewater treatment.

In addition, although it is possible to reduce the risk by coarsening the particles, it is not suitable for industrial large-scale continuous production, and there is a problem that it is difficult to uniformly mix it in terms of use in various applications.

Japanese Laid-Open Patent Publication No. 11-228133 Japanese Laid-Open Patent Publication No. 2002-362921

One of the objects of the present invention is to provide a material containing strontium nitrate or barium nitrate with high safety and easy handling. Specifically, the present invention is to provide a material containing strontium nitrate or barium nitrate, which has a high risk of oxidative force and a high safety that suppresses sensitivity to impact.

That is, the first aspect of the present invention relates to a particulate composition containing strontium nitrate and / or barium nitrate and hydrophobic silica. The hydrophobic silica preferably has a BET specific surface area of 50 to 400 m < 2 > / g.

The particulate composition is preferably of a CLASS 5-Division 5.1 (oxidising solid) according to the United Nations recommendation in accordance with the United Nations Recommendations on the TRANSPORT OF DANGEROUS GOODS - Manual of Tests and Criteria - Third revised edition. It is not dangerous in combustion test.

The particulate composition preferably contains 95.0 to 99.8 mass% of strontium nitrate or barium nitrate.

The particulate composition can be preferably used as a glass raw material.

The particulate composition preferably contains 0.1 to 3.0% by mass of the hydrophobic silica (provided that the total mass of the particulate composition is 100% by mass).

A second aspect of the present invention relates to a method for producing a particulate composition comprising a step of mixing strontium nitrate and / or barium nitrate with hydrophobic silica.

A third aspect of the present invention relates to a glass made from the particulate composition.

A fourth aspect of the present invention relates to a method for preserving strontium nitrate and / or barium nitrate by mixing hydrophobic silica.

According to the present invention, by virtue of the action of a specific silica, it is possible to suppress the combustibility and explosiveness inherently possessed by strontium nitrate and / or barium nitrate, thereby reducing the risk. This makes it possible to enhance the safety in use, storage and transport. In addition, since an explosion-proof facility for securing safety is unnecessary, it can contribute to cost reduction in terms of manufacturing facilities.

(Strontium nitrate and barium nitrate)

The particulate composition of the present invention contains strontium nitrate and / or barium nitrate. The strontium nitrate to be used in the present invention is not particularly limited, and a synthesized strontium nitrate may be used, or a commercially available strontium nitrate may be used. The method of synthesizing strontium nitrate is not particularly limited, and examples thereof include a method of neutralization reaction of strontium hydroxide and nitric acid, a method of converting strontium nitrate to carbonic acid by reacting strontium carbonate and nitric acid, And a method in which sodium nitrate is added to the solution for reaction.

The barium nitrate used in the present invention is not particularly limited, and a synthesized barium may be used, or a commercially available barium nitrate may be used. The method for synthesizing barium nitrate is not particularly limited, and for example, a method of allowing nitric acid to act on barium carbonate or barium sulfide can be given.

(Silica)

Conventional silica has a high affinity with water because a silanol group (Si-O-H) is present on its solid surface. Such silica is referred to as " hydrophilic silica ". On the other hand, a hydrophobic silica having a surface modified by hydrophobic treatment by applying a hydrophobic treatment such as a silane treatment or a silane coupling treatment to the surface of the silica is called "hydrophobic silica". In the present invention, " hydrophobic silica " is used.

There is no limitation on the raw material silica before the hydrophobic treatment, and silica obtained by a known method is used. For example, fumed silica, wet silica and the like are representative.

Examples of the fumed silica include a vapor-phase silica obtained by burning a silicon compound or metal silicon in an oxyhydrogen flame.

Examples of the wet silica include a precipitation method silica in which silica is precipitated in a solution by neutralizing the sodium silicate.

A sol-gel method silica obtained by hydrolyzing an alkoxide of silicon in a functional organic solvent can also be used.

The hydrophobic silica can be obtained by mixing the surface of the hydrophilic silica with a surface treatment agent such as a silane coupling agent such as dimethyldichlorosilane, hexamethyldisilazane or octylsilane, a silane coupling agent such as vinyltrimethoxysilane, a dimethylpolysiloxane, a methylhydrogenpolysiloxane, And the like. However, the surface treatment agent is not limited thereto.

The hydrophobic silica in the present invention preferably has a hydrophobicity of 20% or more, more preferably 30% or more, and still more preferably 50% or more. In addition, the hydrophilic silica exhibits a hydrophobicity of almost 0%. Here, the " degree of hydrophobicity " means the degree of hydrophobicity of the hydrophobic silica dispersed in water and the amount of the organic solvent in the organic solvent-water mixed solution at the time when the total amount of the hydrophobic silica suspended by dropping the organic solvent (for example, methanol) Fraction (% by mass). The measurement can be carried out, for example, by adding 0.2 g of hydrophobic silica to 50 ml of ion-exchanged water and dropping methanol from the burette while stirring with a magnetic stirrer. The mass fraction (%) of methanol in the methanol-water mixed solution at the end point at which the suspended hydrophobic silica gradually precipitates and the total amount thereof sinks is the " degree of hydrophobicity ".

A commercially available product satisfying the above conditions can be used as the hydrophobic silica in the present invention. Examples of the hydrophobic silica include AEROSIL® (AEROSIL® R972, R974, R104, R106, R202, R805, R812, R812S, R816, R7200, R8200, and R9200 manufactured by Ebonic Industries, CAB-O-SIL (R) (CAB-O-SI L (R) TG-C413, TG-3180, TG-7120, TG-818F, TG- TS-620, TS-630, and TS-720), rheological (R) (manufactured by Tokuyama Corp., WACKER (R) HDK-H15, HDK-H18, HDK (trade name) manufactured by Asahi Chemical Industry Co., Ltd., DM-10, DM-20, DM-30, MT-10 and MT- (Nipsil® SS-10, SS-30S, SS-30P, SS-50, and SS-50F manufactured by Tosoh Silica Co., Ltd.) .

The hydrophobic silica has a BET specific surface area of preferably 50 to 400 m 2 / g, more preferably 75 to 300 m 2 / g. The BET specific surface area refers to the value measured by the nitrogen adsorption BET one-point method. The measuring procedure conforms to the provisions of JIS Z 8830.

(Particulate composition)

The particulate composition of the present invention contains strontium nitrate and / or barium nitrate and hydrophobic silica.

The particulate composition of the present invention is not particularly limited, but a particulate composition can be obtained by adding strontium nitrate and / or barium nitrate and hydrophobic silica in the required amounts, respectively, and mixing them. The order of addition of the respective components is not particularly limited. The means for mixing is not particularly limited, and a well-known rotating solid mixer can be appropriately selected. Examples of the rotating solid mixer include a ribbon type, a single shaft type, a V type, a Nauta type, a double cone type, and a cylindrical type.

It is preferable to uniformly mix strontium nitrate and / or barium nitrate with the hydrophobic silica, and it is preferable that the strontium nitrate particles and / or the barium nitrate particles are softly mixed so that crushing does not occur easily. As the strontium nitrate particles and / or the barium nitrate particles are crushed, the granular composition may not be cured and the safety due to the hydrophobic silica may not be improved.

The amount of strontium nitrate or barium nitrate in the particulate composition is not particularly limited, but is preferably 95 to 99.8 mass%, and more preferably 97 to 99.5 mass%.

The amount of the hydrophobic silica in the particulate composition is not particularly limited, but is preferably from 0.1 to 3.0% by mass, more preferably from 0.3 to 2.0% by mass, and particularly preferably from 0.4 to 1.8% by mass. However, the total amount of strontium nitrate, barium nitrate, and hydrophobic silica does not exceed 100% by mass. If the amount of the hydrophobic silica exceeds 3.0% by mass, it is not uniformly mixed with strontium nitrate or barium nitrate, and as a result, there is a fear that problems such as separation, attachment to a container, generation of dust may occur. If the components are not uniformly mixed, there is a fear that the glass composition may be influenced when the glass is produced using the particulate composition. On the other hand, if the amount of the hydrophobic silica is too small, improvement in safety by the hydrophobic silica can not be expected in some cases.

The particulate composition of the present invention can be used for the combustion of a CLASS 5-Division 5.1 (oxidizing solid) according to the UN Recommendations in accordance with the UN Recommendations on the TRANSPORT OF DANGEROUS GOODS - Manual of Tests and Criteria - Third revised edition It is preferable that it does not correspond to dangerous substances in the test. Here, the "combustion test of CLASS 5-Division 5.1 (oxidizing solid) by UN Recommendations" (combustion test (i)) is as follows.

(Combustion test (i))

The combustion test (i) is a test to classify the potential risks of oxidizing power of the test sample. The working sequence is to mix the test sample in the form of granules and the cellulose in a weight ratio of 1: 1 and 4: 1, so that the sum of both is 30 g, to form a circular abstraction. With the ignition device sandwiched between this deposition and the insulating plate, apply for a maximum of 3 minutes until it becomes clear that it is completely ignited or not ignited at all. The average burning time of each test mixture was measured by mixing the reference material (potassium bromate) and cellulose in a weight ratio of 3: 2, 2: 3, 3: 7 Compare the combustion time of one standard mixed sample.

(Risk assessment)

When the average combustion time of each test mixture is less than or equal to the combustion time of the standard mixture of potassium bromate and cellulose at a mixing weight ratio of 3: 2, it exceeds the combustion time of the standard mixture of "mixture grade 1" and mixing ratio 3: 2 And less than the burning time of a standard mixed sample of 2: 3 by mixing weight ratio is less than the burning time of a standard mixed sample exceeding the burning time of a standard mixed sample of "container grade 2", mixing weight ratio of 2: 3 and mixing weight ratio of 3: 7 &Quot; Packing grade 3 ". Mixing weight ratio of potassium bromate and cellulose exceeding the burning time of the standard mixed sample of 3: 7 does not correspond to CLASS 5-Division 5.1 (oxidizing solid).

Further, the particulate composition of the present invention has a low risk when evaluated by the combustion test (ii) and the fall-type impact sensitivity test. &Quot; Combustion test (ii) and fall type impact sensitivity test " is a test carried out in the following order.

(Combustion test (ii))

The combustion test (ii) is a test to classify the potential risks of oxidizing power of the test sample. As the working sequence, firstly, the test sample is divided into a granular phase and wood flour is mixed at a mass ratio of 1: 1 and 4: 1 so that the sum of both is 30 g, thereby forming a circular abstract deposition. A nichrome wire heated to 1000 캜 is brought into contact with the base of the deposition to check whether the test mixed sample is burnt, and if it is burnt, the burning time is measured.

The burning time of the shorter time in each burning time of each of the mixed samples thus measured was compared with the burning time of the standard mixed sample (mixture of standard substance (potassium perchlorate or potassium bromate) and wood powder at a mass ratio of 1: 1) . Quot; Rank 1 " where the burning time of the test mixed sample is less than or equal to the burning time of the standard mixed sample of potassium bromate is referred to as " Rank 1 ", that the burn time of the standard mixed sample of potassium bromate exceeds the burning time of the standard mixed sample of potassium perchlorate Quot; Rank 2 ", and those exceeding the burning time of the standard mixed sample of potassium perchlorate are referred to as " Rank 3 ".

(Fall type impact sensitivity test)

The fall-type impact sensitivity test is a test for classifying the sensitivity of the test sample to impact. As a working procedure, firstly, a steel ball is dropped from a certain height for a mixture of a reference material (potassium chlorate or potassium nitrate) and red lime, and the drop height is increased or decreased by 50% Find the explosion point (the height that explodes with a probability of 50%). For the mixture of test sample and lime, the same test of dropping steel balls from each 50% explosion point is conducted 10 or 40 times to evaluate explosion and non-explosion. In the present specification, "potassium chlorate method" is used when potassium chlorate is used as a standard material, and "potassium nitrate method" when potassium nitrate is used.

Ten tests were conducted to drop the steel ball from the 50% explosion point by the potassium chlorate method, and when the "explosion" occurred in all of the ten times, it is set to "Rank 1". If both "explosion" and "fire explosion" occur in 10 tests, additional 30 tests are conducted. In case of "explosion" 20 times or more in a total of 40 tests, "rank 1" and "explosion" When it is less than times, "rank 2" is assumed. If all of the first 10 tests have resulted in a "fire explosion", the test is carried out by the potassium nitrate method.

Rank 2 "in the case of all" explosion "in 10 tests in which a steel ball is dropped from a 50% explosion point by the potassium nitrate method, and" Rank 3 "in case of all" explosion explosion ". In the case of "explosion" or "explosion explosion" in 10 tests, an additional 30 tests were conducted. In the case of "explosion" 20 times or more in a total of 40 tests, "rank 2" When it is less than times, "rank 3" is assumed.

(Risk assessment)

The risk of the test sample is determined from the results of the combustion test (ii) and the fall-type impact sensitivity test. In the burning test (ii) or the fall type impact sensitivity test, all of the samples which became " rank 1 " were classified as " class 2 oxidative solids ", combustion test Ranked oxidative solid ", combustion test (ii), or burnout test (ii), one of which is" Rank 2 "and the other one is" Rank 3 " And " Rank 3 " in the fall type impact sensitivity test are classified as " non-hazardous materials ".

As for the classification of the above risk assessment, the larger the number of "class", the lower the risk as dangerous goods. In the case of non-dangerous materials, the safety, even in the case of manufacturing, transportation and storage, Which means that there is no problem.

(Glass)

The present invention also relates to a glass containing the particulate composition as a raw material. In the production of glass, it is important to select the raw materials for the combination thereof. When strontium nitrate and / or barium nitrate are used, the solubility of the raw material is good and the fineness is excellent. The method for producing the glass of the present invention is not particularly limited, but a known method (for example, a melting method) can be used. That is, the glass raw material containing silica, alumina, boric acid, and the strontium nitrate and / or barium nitrate of the present invention and other necessary components of the present invention so that the glass of the present invention has a predetermined composition expressed on an oxide basis, In the crucible. Thereafter, it is heated and melted in a melting furnace such as an electric furnace or a gas furnace. After melting, refining and stirring are carried out as necessary to homogenize the glass, and then molten glass is poured into the molding die to quench the molten glass, thereby forming and cooling the molten glass in the quenching furnace.

The glass taken out from the throat furnace can be cut, ground, and polished as necessary to obtain various substrate materials, structural members, and transmission optical system materials.

(Preservation method)

The present invention also relates to a method for preserving strontium nitrate and / or barium nitrate.

Strontium nitrate or barium nitrate may oxidize flammable substances and cause severe combustion or explosion.

By mixing hydrophobic silica when storing strontium nitrate or barium nitrate, it is possible to reduce the risk of the above-described intensive combustion or explosion, and it can be handled as high-safety strontium nitrate and / or barium nitrate.

Strontium nitrate or barium nitrate preserved by the preservation method of the present invention can be preferably used as a glass raw material.

Example

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, "% " means "% by mass " unless otherwise stated.

(Combustion test)

The combustion test was carried out according to the method of the combustion test (i) or the combustion test (ii) according to the above UN Recommendations and Test Manual.

(Fall type impact sensitivity test)

A fall-type impact sensitivity test was conducted according to the above-described fall-type impact sensitivity test method.

(Evaluation of particles containing strontium nitrate)

(Example 1)

AEROSIL R972 (surface-treated hydrophobic silica, hydrophobicity 35%, specific surface area 110 m < 2 > / g, manufactured by Evonik Industries Co., Ltd.) was added to 2.51 kg of 500 kg of strontium nitrate so that the addition amount as hydrophobic silica was 0.5% And mixed with a ribbon blender to prepare a particulate composition 1. The obtained particulate composition 1 was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 1.

(Example 2)

A particulate composition 2 was prepared in the same manner as in Example 1 except that the addition amount of AEROSIL R972 was changed to 0.75 mass% of the total mass of the particles. The obtained particulate composition 2 was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 1.

(Example 3)

A particulate composition 3 was prepared in the same manner as in Example 1 except that the addition amount of AEROSIL R972 was changed to 1.0 mass% of the total mass of the particles. The obtained Particulate Composition 3 was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 1.

(Example 4)

The particulate composition 4 was produced in the same manner as in Example 1 except that the hydrophobic silica was changed to Nipsil SS-30P (surface-treated hydrophobic silica, degree of hydrophobicity 60%, specific surface area 125 m 2 / g, manufactured by Tosoh Silica KK) Respectively. The obtained particulate Composition 4 was subjected to a combustion test. The results are shown in Table 1.

(Example 5)

The particulate composition 5 was prepared in the same manner as in Example 1 except that the hydrophobic silica was changed to Nipsil SS-50F (surface-treated hydrophobic silica, degree of hydrophobicity 60%, specific surface area 82 m2 / g, manufactured by Tosoh Silica KK) Respectively. The obtained particulate Composition 5 was subjected to a combustion test. The results are shown in Table 1.

(Example 6)

A particulate composition 6 was prepared in the same manner as in Example 1 except that the kind of the hydrophobic silica was changed to Nipil SS-30P by 1.0 mass% of the total mass of the particles. The particulate composition 6 thus obtained was subjected to a combustion test. The results are shown in Table 1.

(Example 7)

A particulate composition 7 was prepared in the same manner as in Example 1, except that the kind of the hydrophobic silica was changed to Nipil SS-50F by 1.0 mass% of the total mass of the particles. The obtained particulate composition 7 was subjected to the combustion test of the dangerous materials class 1. The results are shown in Table 1.

(Comparative Example 1)

A comparative particulate composition 1 was prepared in the same manner as in Example 1 except that no silica was used. The comparative particulate composition 1 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

(Comparative Example 2)

A comparative particulate composition 2 was produced in the same manner as in Example 1 except that the type of silica was changed to AEROSIL 200 (hydrophilic silica, hydrophobicity 0%, specific surface area 200 m 2 / g, manufactured by Ebonic Industries). The comparative particulate composition 2 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

(Comparative Example 3)

Comparative comparative particulate composition 3 was prepared in the same manner as in Example 1 except that the type of silica was changed to Nipsil LP (hydrophilic silica, hydrophobicity 0%, specific surface area 210 m 2 / g, manufactured by Tosoh Silica KK). The comparative particulate composition 3 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

(Comparative Example 4)

The comparative particulate composition 4 was prepared in the same manner as in Example 1 except that the kind of silica was changed to Nipsil LP with the addition amount being 3.0 mass% of the total mass of the particles. The Comparative Comparative Particle Composition 4 was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

(Comparative Example 5)

Except that the kind of silica was changed to MK Silica FINES (glass raw material high purity silica, hydrophobicity 0%, average particle size 40 탆, manufactured by Kyoritsu Material Co., Ltd.), and the addition amount thereof was changed to 30 mass% In the same manner, comparative particulate composition 5 was prepared. The comparative particulate composition 5 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

(Comparative Example 6)

Except that the kind of silica was changed to MK Silica 20/250 (glass raw material high purity silica, hydrophobicity 0%, average particle size 120 탆, manufactured by Kyoritsu Material Co., Ltd.), and the addition amount was changed to 30 mass% 1, comparative particulate composition 6 was prepared. The comparative particulate composition 6 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. The results of the risk evaluation are shown in Table 2.

From the results shown in Table 1, it was found that the particulate compositions of the present invention (Examples 1 to 7) containing strontium nitrate and hydrophobic silica all had a low risk of oxidizing power in the combustion test. It was also found that the sensitivity to impact was low even by the fall-type impact sensitivity test. On the other hand, from the results shown in Table 2, the effect of eliminating the risk was not confirmed in the particle compositions containing no hydrophobic silica (Comparative Examples 1 to 6). Thus, from the above results, it has become clear that the particulate composition of the present invention is excellent in that the risk is excluded and the safety is higher.

(Evaluation of particles containing barium nitrate)

(Example 8)

3.78 kg of AEROSIL R972 was added to 500 kg of barium nitrate so that the amount added as hydrophobic silica was 0.75 mass% of the total mass of the particles, and the mixture was mixed with a ribbon blender to prepare a particulate composition 8. The obtained particulate composition 8 was subjected to a fall-type impact sensitivity test. The results are shown in Table 3.

(Example 9)

A particulate composition 9 was prepared in the same manner as in Example 8 except that the amount of AEROSIL R972 added was changed to 1.0 mass% of the total mass of the particles. The obtained particulate composition 9 was subjected to a combustion test. The results are shown in Table 3.

(Example 10)

A particulate composition 10 was prepared in the same manner as in Example 8 except that the addition amount of AEROSIL R972 was changed to 1.5 mass% of the total mass of the particles. The obtained particulate composition 10 was subjected to a combustion test and a fall type impact sensitivity test. Table 3 shows the results of the risk evaluation.

(Comparative Example 7)

A comparative particulate composition 7 was prepared in the same manner as in Example 8 except that silica was not used. The comparative particulate composition 7 thus obtained was subjected to a combustion test and a fall type impact sensitivity test. Table 3 shows the results of the risk evaluation.

(Comparative Example 8)

A comparative particulate composition 8 was prepared in the same manner as in Example 8 except that the kind of silica was changed to AEROSIL 200 and the addition amount was changed to 30 mass% of the total mass of the particles. The obtained particulate composition 8 was subjected to a combustion test and a fall type impact sensitivity test. Table 3 shows the results of the risk evaluation.

Barium nitrate is a substance which is classified as dangerous goods classified as "Container Class 2" in the combustion test of CLASS 5-Division 5.1 (oxidizing solid) normally recommended by the United Nations. The results of Table 3 show that the particulate composition of the present invention containing barium nitrate and hydrophobic silica (Examples 8 to 10) suppresses the potential danger of oxidative power and sensitivity to impact, It is excellent in that it is modified with high material. The effect of reducing the risk was not confirmed in the particle composition containing no hydrophobic silica (Comparative Example 7 · 8).

Glass containing strontium nitrate and / or barium nitrate and hydrophobic silica, which contains a particulate composition with reduced risk, as a raw material has no safety problem even if it is produced by a manufacturing process using a general chemical as a raw material. Further, a glass containing a particulate composition containing strontium nitrate and / or barium nitrate and a hydrophobic silica as a raw material is not significantly different from a conventional glass containing strontium nitrate and / or barium nitrate as a raw material Glass can be obtained.

(Production Example of Glass)

The ingredients of the combination materials in Table 4 (parts by weight, parts by weight) are well mixed, placed in a platinum crucible, and covered with a platinum cap. The crucible was placed in an electric furnace and heated, melted and stirred at about 1500 to 1680 DEG C, homogenized and refined, and then poured into a mold. After the glass was solidified, the furnace was moved to an electric furnace heated near the glass stand- The glass composition can be prepared by quenching.

Claims

Strontium nitrate and / or barium nitrate,
A particulate composition containing hydrophobic silica.

The method according to claim 1,
In the combustion test of the CLASS 5-Division 5.1 (oxidizing solid) according to the UN Recommendations in accordance with the UN Recommendations and Test Manual "Recommendations on the TRANSPORT OF DANGEROUS GOODS - Manual of Tests and Criteria - Third revised edition" Particulate composition.

3. The method according to claim 1 or 2,
Wherein said strontium nitrate or barium nitrate is contained in an amount of 95.0 to 99.8 mass%.

4. The method according to any one of claims 1 to 3,
Wherein the particulate composition is used as a glass raw material.

5. The method according to any one of claims 1 to 4,
Wherein the hydrophobic silica is contained in an amount of 0.1 to 3.0% by mass (provided that the total mass of the particulate composition is 100% by mass).

6. The method according to any one of claims 1 to 5,
Wherein the hydrophobic silica has a BET specific surface area of 50 to 400 m < 2 > / g.

The method of producing a particulate composition according to any one of claims 1 to 6, comprising a step of mixing strontium nitrate and / or barium nitrate with hydrophobic silica.

A glass produced from the particulate composition according to any one of claims 1 to 6.

A method for preserving strontium nitrate and / or barium nitrate by mixing hydrophobic silica.