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CN-122003385-A - Silicate mineral and method for producing same

CN122003385ACN 122003385 ACN122003385 ACN 122003385ACN-122003385-A

Abstract

Silicate minerals having an average particle diameter of more than several hundred nm and free from impurities such as crystalline silica can be provided. The silicate mineral, crystalline silica and asbestos of the present invention each have a content of 0.1% by weight or less. The mineral preferably contains carbonate, preferably having an average particle size of 100nm or more. The minerals are used in cosmetics, sanitary products, medicines and foods. The silicate mineral of the present invention is obtained by subjecting a natural silicate mineral to a warm water treatment, a hot water treatment or a hydrothermal reaction treatment at a pH of 9.4 or less.

Inventors

  • ADSCHIRI TADAFUMI
  • Da Yuanzhi
  • NAKANISHI RYO

Assignees

  • 株式会社超级纳米设计

Dates

Publication Date
20260508
Application Date
20241120
Priority Date
20231124

Claims (18)

  1. 1. A silicate mineral, wherein the content of crystalline silica and asbestos is 0.1 wt% or less.
  2. 2. The silicate mineral according to claim 1, which contains carbonate.
  3. 3. The silicate mineral powder according to claim 1, wherein the primary particles have an average particle diameter of 100nm or more.
  4. 4. Silicate mineral powder according to claim 1, wherein the amount of 0.01M NaOH aqueous solution required in the following method is 180 μl or more, the method comprising: (1) 0.1g of silicate mineral powder was dispersed in 10ml of water, (2) After adding 2g of NaCl, the pH was adjusted to 4 or less with 0.12M diluted hydrochloric acid, (3) After the pH was adjusted to 4 by adding 0.01M NaOH aqueous solution, the required amount of 0.01M NaOH aqueous solution was measured from this point to pH 9.
  5. 5. A cosmetic comprising the silicate mineral according to any one of claims 1 to 4.
  6. 6. A sanitary article comprising the silicate mineral according to any one of claims 1 to 4.
  7. 7. A pharmaceutical product comprising the silicate mineral according to any one of claims 1 to 4.
  8. 8. A food product comprising the silicate mineral according to any one of claims 1 to 4.
  9. 9. A method for producing a silicate mineral, which comprises a step of subjecting a silicate mineral derived from a natural mineral to a warm water treatment, a hot water treatment or a hydrothermal reaction treatment at a pH of 9.4 or less.
  10. 10. The method according to claim 9, wherein the warm water or the hot water treatment or the hydrothermal reaction treatment is performed in the coexistence of carbonic acid or CO 2 .
  11. 11. The method according to claim 9, wherein the warm water or the hot water treatment or the hydrothermal reaction treatment is performed in the coexistence of Mg ions.
  12. 12. The method according to claim 9, wherein the temperature in the warm water or the hot water treatment or the hydrothermal reaction treatment is 70 ℃ or more and 370 ℃ or less, and the pressure is a saturated vapor pressure of water or more.
  13. 13. The method according to claim 9, wherein the warm water or the hot water treatment or the hydrothermal reaction treatment is performed for a time of 1 minute or more.
  14. 14. The method according to claim 9, wherein the warm water or the hot water treatment or the hydrothermal reaction treatment is performed using a batch apparatus or a semi-batch apparatus.
  15. 15. The method of claim 14, wherein the reaction device is the semi-batch device, The amount of the aqueous solvent to be supplied to the semi-batch apparatus is 0.1 times or more of the theoretical amount of saturated dissolution of crystalline silica contained in the silicate mineral as a raw material in a reaction solution containing coexisting ions in a reaction field.
  16. 16. The method of claim 14, wherein the reaction device is the semi-batch device, The amount of crystalline silica contained in the silicate mineral as a raw material charged into the semi-batch apparatus is 10 times or less of the theoretical amount of saturated dissolution of the reaction solution containing coexisting ions in the reaction field.
  17. 17. The method according to claim 9, wherein the silicate mineral is supplied in a suspended state into water using a flow-through apparatus, and the warm water or the hot water treatment or the hydrothermal reaction treatment is performed.
  18. 18. The method according to claim 17, wherein a concentration of the aqueous slurry of silicate mineral to be supplied to the flow-through device is 0.1 times or more of a theoretical amount of saturated dissolution of crystalline silica contained in the silicate mineral as a raw material in a reaction solution containing coexisting ions in a reaction field.

Description

Silicate mineral and method for producing same Technical Field The present invention relates to silicate minerals and a method for producing the same. Background Silicic acid compounds are also various in minerals and widely used in cosmetics, foods, medicines, and industrial products. In the deep ground, groundwater is heated by volcanic activity, becomes hot water (subcritical/supercritical water) at high temperature and high pressure, dissolves rock to form a supercritical water solution state, and is reduced in solubility and precipitated when depressurized and cooled near the ground surface. This is the principle of vein formation. As is apparent from an examination of the above-ground earth and sand components, a silicic acid compound is a main constituent component thereof. As the silicic acid compound, not only silica SiO 2 but also calcium silicate, magnesium silicate, iron silicate, sodium silicate, and the like containing various metals such as Al, ca, fe, K, na, mg, or minerals containing various metals, and hydrates thereof are also formed in large amounts. TABLE 1 classification of silicate minerals According to the principle of precipitation, the impurities are contained in large amounts. Among them, siO 2 as a constituent is also often contained as an impurity. The purpose of the present invention is to remove these impurities generated during the precipitation of silicate minerals, and to target aluminum silicate, calcium silicate, magnesium silicate, iron silicate, and the like, and their hydrates. In the following, the present technique is described with reference to hydrous magnesium silicate (also referred to as talc or the like), but the present technique is principally applicable to other silicate minerals. Hydrous magnesium silicate is widely used in cosmetics, foods, medicines, and industrial products, but is a natural mineral and therefore contains impurities in many cases. In commercial use, toxic substances, heavy metals and the like are separated and removed for reuse. However, in many cases, such materials as talc, which is a natural mineral, are easily mixed with components such as SiO 2 that are likely to be simultaneously deposited during mineral formation, and these components that are likely to be simultaneously deposited are often mixed into products. For example, there are many cases where a small amount of tremolite or chrysotile is caused by asbestos. The mixing of asbestos is not allowed not only in the fields of cosmetics, foods, medicines, etc., but also in industrial products, and the mixing of crystalline SiO 2 (also called crystalline silica, quartz, etc.) has recently been regarded as a problem. However, the formation of minerals at the ground is a precipitation affected by temperature and pressure, and the composition of the precipitates varies depending on the location of mineral exploitation. The use of a portion containing almost no impurity after detailed investigation and selection has been the only solution, but even if the content of the impurity is very small, the use of the portion containing the impurity is still a great problem particularly in the application fields of medical treatment, foods, cosmetics and the like. Further, focusing on crystalline SiO 2, since physical properties required for conventional component separation such as specific gravity of hydrous magnesium silicate and SiO 2 are almost the same, it is impossible to separate them by centrifugation, sedimentation separation, specific gravity separation, or adsorption operation by chromatography or the like. Here, there has been proposed artificial synthesis of talc in a fine particle shape by hydrothermal synthesis including supercritical field (see patent document 1). Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2014-520743 Disclosure of Invention However, the synthetic talc obtained by the method described in patent document 1 has a particle diameter as small as 20nm to 100nm. In the field of application of hydrous silicic acid compounds such as talc, natural minerals are crushed and sieved for use, and therefore, the particle size is several tens of μm or more, and even when the particle size is small, it is desirable to provide talc having a larger particle size from the viewpoint of safety (nano risk) for users. In principle, particle size can be grown by hydrothermal method or the like, but artificial synthesis has problems in terms of manufacturing cost, production efficiency, and optimization of properties, and it is practically impossible to become a method for industrially producing particles of several hundred nm or more. Therefore, even if it is desired to remove impurities from natural minerals, the dissolution of SiO 2 impurities from a mixed system of hydrous magnesium silicate and SiO 2, which is an impurity, means that the impurities can be dissolved by setting alkaline conditions, but at the same time hydrous magn