JP3092085B1 - Purification of magnesium silicate ore containing carbonate as impurity - Google Patents

Abstract

An object of the present invention is to provide an efficient purification method for purifying unused carbonate silicate ore carbonate impurities by acid treatment. SOLUTION: When refining magnesium silicate ore containing carbonate as an impurity, an alkali halide solution is added to a solvent to prevent damage to the magnesium silicate and to reduce the acid concentration. 0.2-4.
5N, a method in which the amount of an acid is set to a necessary equivalent for dissolving a carbonate, and the titration rate of the acid is set to 1/100 or less of the required equivalent to reduce the damage to reduce the damage. According to the above method, damage to the magnesium silicate can be prevented, and the dissolution of carbonate-based impurities can be promoted. As a result, the magnesium silicate ore can be efficiently purified. Becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying magnesium silicate ore containing carbonate as an impurity, and more particularly to a method for purifying magnesium silicate ore which is difficult to purify by a conventional method. The present invention relates to a new method for refining a magnesium silicate ore capable of improving the refining efficiency without damaging a refined magnesium silicate mineral. INDUSTRIAL APPLICABILITY The present invention is useful as a method for refining ore that enables effective utilization of low-grade and unused ore containing carbonate minerals as impurities.

[0002]

BACKGROUND ART Magnesium silicate minerals (Sepiolite _{(Mg 8 Si 12 O 30 (} OH) 4 (H 2 O) 4 · 8H 2
O), sepiolite (alias of sepiolite), palygorskite (Mg ₅ Si ₈ O ₂₀ (OH) ₂ (OH ₂ ) _4. (H ₂
O) ₄ ), attapulgite (alias of palygorskite), talc (Mg ₃ Si ₄ O ₁₀ (OH) ₂ , alias: talc), etc. are many fine and highly adsorptive and viscous minerals, building materials, paints, catalysts Used in various fields such as carriers,
In recent years, research on utilization of high-performance materials such as high-density filters and harmful gas removal materials and asbestos substitutes has been made, and a stable supply of high-quality raw materials is urgently desired.

However, since only high-purity raw materials have been mined so far, high-purity raw materials tend to be depleted year by year, which has become a problem. To solve this,
There is a pressing need to effectively utilize low-grade ores containing carbonate minerals as impurities, which are present in large quantities worldwide. In the present invention, in the purification of a magnesium silicate ore in which the primary particles have a fine particle size, a high viscosity and a high caking property, and are difficult to purify, purification is performed by adjusting the pH so that only the carbonate is dissolved. It is about how to increase efficiency. This will increase the utilization of low-grade, unused magnesium silicate ores, and address the depletion of resources used in oil drilling slurries, chemical carriers, moisture conditioning and deodorizing materials, and ceramic raw materials. Becomes possible.

[0004] In the air classification or dispersion classification of magnesium silicate in water, most of the ore is fine particles below the classification limit of water and the ore has a fibrous entanglement. Not. Conventionally, for example,
Japanese Patent Publication No. 55-47937 proposes that after mixing hydrogen peroxide or a polyhydric alcohol, the mountain skin (including sepiolite and the like) is swollen by heating, and then the impurities are precipitated and purified. However, hydrogen peroxide has a high volatility at the time of heating, so that a stable effect cannot be expected, and polyhydric alcohol has a viscosity lowering effect, so that the thickening effect of magnesium silicate may be impaired. In addition, Japanese Unexamined Patent Publication
No. 1-295221 proposes to heat sepiolite ore to facilitate separation of impurities and target minerals, and then pulverize and perform air classification. However, since the heating temperature must be increased, there is a possibility that the moisture and viscosity of the magnesium silicate hydrate may be impaired. Furthermore, in Clay Science, Vol. 31, No. 4, pp. 196-201, 1992,
Although hydrochloric acid purification of sepiolite has been reported, since the pH is not controlled, the amount of acid added tends to be excessive,
Part of the magnesium silicate to be recovered is also dissolved, and the surface characteristics and particle size are deteriorated, and there is a high possibility of damaging applied characteristics such as viscosity.

[0005]

As described above, various methods for refining magnesium silicate ore have already been developed, but the conventional methods have insufficient refining efficiency or damage the refined product. And had problems such as giving. Under these circumstances, the present inventors have conducted intensive studies with the aim of developing a new purification method capable of solving the above-mentioned problems in view of the above-mentioned conventional technology, and as a result, the acid treatment It has been found that the desired object can be achieved by adding an alkali halide to a solvent in the purification by the above method, and the present invention has been completed. In the present invention, potassium chloride is added to a solvent in the purification by acid treatment to reduce the damage so that the purification efficiency can be increased without damaging the magnesium silicate mineral.

That is, an object of the present invention is to provide a method for improving the purification efficiency without damaging the magnesium silicate mineral in order to fundamentally solve the above-mentioned problems. In the purification step by the treatment with a mineral acid, a solution for protecting a magnesium silicate such as an alkali halide and promoting the dissolution of a carbonate is added.

[0007]

The present invention for solving the above-mentioned problems comprises the following technical means. (1) A method for purifying a magnesium silicate ore containing a carbonate as an impurity, in which a mineral acid is used to promote the dissolution of the carbonate and prevent the dissolution of the magnesium silicate. A purification treatment method comprising adding an alkali halide solution to a solvent. (2) The method according to the above (1), wherein the concentration of the mineral acid to be used is set to a concentration of 0.2 to 4.5 N to reduce damage to the magnesium silicate. (3) The titer of the mineral acid to be used is defined as a necessary equivalent calculated from the average impurity carbonate content in the magnesium silicate ore, and the titration speed is set to 1/100 or less of the required equivalent. ) Described method.

[0008]

Next, the present invention will be described in more detail. In the method of the present invention, in order not to damage the magnesium silicate mineral, a protective alkali halide solution is added, and the concentration of the added acid is adjusted so as to dissolve only weak carbonate impurities in the acid. From 0.2 to
In the range of 4.5N, the titration is performed up to the required equivalent of the acid calculated from the content of the carbonate, and the titration speed is set to be not more than one hundredth per minute of the required equivalent of the acid. The reason for adding an alkali halide is that when divalent magnesium ions elute from the surface, by increasing the ion concentration of the halide in the solution in advance, the solubility of the magnesium halide is not so high, This is because dissolution of magnesium from the magnesium silicate is hindered, and it is considered that only dissolution of the carbonate proceeds.

In the method of the present invention, a low-grade ore containing a carbonate mineral as an impurity can be used as a purified magnesium silicate ore. As these ores,
Sepiolite (Japanese name: sepiolite, skin bark, alias: mountain cork, mountain leather, mountain wood), palygorskite (alias: attapulgite), smectite (montmorillonite, saponite, hectorite stevensite), bentonite, talc (talc) Vermiculite, mica clay mineral, chlorite and the like are exemplified. In the method of the present invention, first, a predetermined amount of magnesium silicate ore containing carbonate as an impurity is collected, pulverized by an appropriate means, and sieved to 200 μm or less. In this case, the finer the particle, the quicker the reaction. However, for the purpose of viscosity, it is desirable to use a long fibrous mineral. Next, an alkali halide solution of 0.2 to 2N in an amount of 3 to 10 times the weight of the ore is added, and mixed and stirred for about 1 hour with a stirrer. in this case,
Suitable examples of the alkali halide include potassium chloride, sodium chloride, lithium chloride, potassium bromide, sodium bromide, lithium bromide, potassium iodide, sodium iodide, and lithium iodide. These are used after being dissolved in an aqueous solvent. Examples of the acid used as a solution for dissolving impurities in the method of the present invention include hydrochloric acid, nitric acid, and sulfuric acid, and hydrochloric acid is the most preferred acid in terms of cost and handling. These acids are prepared by converting an acid having a concentration of 0.2 to 4.5 N, preferably 1 to 2 N, from the content of carbonate in the following formulas (1), (2),
Add slowly to the equivalent at a titration rate of one hundredth per minute or less, preferably one thousandth per minute of the required equivalent calculated by (3) and the like. If the final pH is acidic, neutralize with an alkaline solution such as sodium hydroxide. afterwards,
By washing with pure water or tap water or the like, filtering with a centrifuge, a filter press, or the like, drying, and then crushing lightly to obtain a processed product, the purification process can be performed with less damage.

Formula (1) Dolomite CaMg (CO ₃ ) ₂ + 4HCl → CaCl ₂ + MgCl ₂ + 2CO ₂ + 2H ₂ O Formula (2) Calcite CaCO ₃ + 2HCl → CaCl ₂ + CO ₂ + H ₂ O Formula (3) Magnesite MgCO ₃ + 2HCl → MgCl ₂ + CO ₂ + H ₂ O

In the above-mentioned purification step, by adding an alkali halide solution, and by adjusting the concentration, amount and rate of addition of the acid in an appropriate range, the damage of the acid to the magnesium silicate is reduced. However, the dissolution of only the carbonate can be promoted, and the purification efficiency of the magnesium silicate ore can be significantly improved.

[0012]

Next, the present invention will be specifically described based on examples, but the present invention is not limited to only the examples. Example 1 Sepiolite purity 20.8 in 1 liter of 1N potassium chloride
% Of Turkish white sepiolite raw material A20 containing 77.3% of dolomite (CaMg (CO ₃ ) ₂ ) as impurities
The solution in which 0 g was suspended was mixed and stirred, and 1N hydrochloric acid was added dropwise at a rate of 1 / 1,000 equivalent per minute. Assuming that all analytical values of CaO are derived from dolomite, the equation (1)
The theoretical value of the required hydrochloric acid was determined from the above, and this equivalent was added.
Thereafter, the excess acid was neutralized with 1N NaOH, washed with pure water, suction filtered, dried at 110 ° C. for 48 hours, and pulverized.

Table 1 shows the results of treating the Turkish sepiolite with hydrochloric acid. When the dolomite content was calculated from the composition of CaO, it could be reduced from 77.3% by weight before the acid treatment to 5.3% by weight after the treatment. The surface area is from 85 m ² / g before the treatment to 365 m ² / g after the treatment.
/ G could be increased. In powder X-ray diffraction, the peak of dolomite as an impurity could be reduced to 1/11 that of the ore, and the peak of sepiolite could be increased to about 5 times (FIG. 1).

Comparative Example 1 Using the same raw material A as in Example 1, a solution in which 200 g of a sample was suspended in 1 liter of distilled water was mixed and stirred, and 1N hydrochloric acid was added dropwise at a rate of 1 / 1,000 equivalent per minute. did. Assuming that all the analytical values of CaO were derived from dolomite, the required theoretical value of hydrochloric acid was determined from equation (1) and added until the equivalent value of the theoretical value was reached. Thereafter, the excess acid was neutralized with 1N NaOH, washed with pure water, suction-filtered, dried and pulverized.

Table 1 shows the results of treating the Turkish sepiolite with hydrochloric acid. When the dolomite content was calculated from the composition of CaO, it was reduced from 77.3% by weight before the acid treatment to 19.1% by weight after the treatment.
The rate of decrease was worse than that. The surface area is 8 before treatment.
It increased from 5 m ² / g to 311 m ² / g after the treatment, but was inferior to that of Example 1 described above. In the powder X-ray diffraction, the impurity dolomite peak was one-fifth that of the ore and the sepiolite peak was about four times higher, but inferior to Example 1 described above (FIG. 1).

Comparative Example 2 A sample 200 was added to 1 liter of distilled water using a Turkish sepiolite raw material B containing 54.0% of dolomite as an impurity.
g of the suspension was mixed and stirred, and 4.5N hydrochloric acid was added dropwise thereto at a sufficient rate of 1 equivalent per minute. Assuming that all analytical values of CaO are derived from dolomite, the equation (1)
From the theoretical value of the required hydrochloric acid, and the equivalent of 0,0.
2,0.4,0.6,0.8,1.0,1.2,1.4
Added until doubled. Thereafter, the excess acid was removed with 1N NaO.
The solution was neutralized with H, washed with pure water, suction-filtered, dried and pulverized.

Table 1 shows the results of treating the Turkish raw material sepiolite B with hydrochloric acid. When the dolomite content is calculated from the composition of CaO, the content of the dolomite is from 54.0% by weight before the acid treatment to 49.1% after the treatment when the acid equivalent is 0.2 to 1.0.
Although reduced to 11.9% by weight, the reduction rate was inferior to that of Example 1 described above. The surface area is 159 before the treatment.
It increased from m ² / g to 295 m ² / g after the treatment, but was inferior to Example 1 described above. In the powder X-ray diffraction, the impurity dolomite peak was one-fifth that of the ore and the sepiolite peak was approximately doubled, but it was inferior to Example 1 described above (FIG. 2). Acid equivalent of 1.2 to
In 1.4, the dolomite content was as small as 2.1 to 2.0%, the surface area was as large as 369 to 327 m ² / g, and almost no dolomite peak was observed in powder X-ray diffraction. The peak of sepiolite was equal to or lower than that of the original ore, indicating that it was damaged.

[0018]

[Table 1]

[0019]

As described above in detail, the present invention relates to a method for purifying a magnesium silicate ore containing a carbonate as an impurity, and for dissolving the carbonate using a mineral acid for the purification. The present invention relates to a purification method comprising adding an alkali halide solution to a solvent in order to promote the dissolution of magnesium silicate and promote the dissolution of magnesium silicate. According to the present invention, 1) adding an alkali halide solution By doing so, it is possible to reduce the damage of the acid to the magnesium silicate and promote the dissolution of only the carbonate. 2) Adjust the concentration, amount and rate of addition of the acid to an appropriate range. Thus, the present invention provides a method for efficiently purifying unused magnesium silicate ore by acid treatment. When contributes to industry is extremely large, special effect can be obtained.

[Brief description of the drawings]

FIG. 1 shows powder X-ray diffraction patterns of Examples and Comparative Examples (ores and treated samples) of the present invention.

FIG. 2 shows a powder X-ray diffraction pattern of Comparative Example 2 (treated sample).

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaki Maeda 54 Togo, Togo, Azamachi, Chita-gun, Aichi Prefecture, Japan (72) Inventor Keiichi Inukai 1-605, Nishifushiya, Nakagawa-ku, Nagoya City, Aichi Prefecture (72) Inventor Fumihiko Ohashi 2 Sandel 3C, 169, Hirade-cho, Nishi-ku, Nagoya, Aichi (72) Inventor Masaya Suzuki 4-8-212, Matsusaka-cho, Tajimi-shi, Gifu (72) Inventor Hiroyasu Sato 1780, Nagaoka, Yamato-cho, Sakata-gun, Shiga Omi Mining Co., Ltd. (72) Inventor Tsutomu Sawada 1780 Nagaoka, Yamato-cho, Sakata-gun, Shiga Prefecture Omi Mining Co., Ltd. (72) Inventor Hiroyuki Itahara 1780 Nagaoka, Yamato-cho, Sakata-gun, Shiga Prefecture Omi Mining Co., Ltd. (72) Inventor Tatsuo Kimura 2946-5 Ushiyama-cho, Kasugai-shi, Aichi Examiner Yoshihisa Seki (56) References K. Inukai, et. al, "Purification of Turkisepisolate through through hydrochloric acid treatment", Applied Clay Science, 1994, vol. 9, p. 11-29 (58) Field surveyed (Int. Cl. ⁷ , DB name) C01B 33/20-33/46 JICST file (JOIS)

Claims (3)

(57) [Claims] 1. A method for purifying a magnesium silicate ore containing a carbonate as an impurity, wherein for the purification, dissolution of the carbonate is promoted by using a mineral acid to dissolve the magnesium silicate. A purification method comprising adding an alkali halide solution to a solvent to prevent the purification. 2. The method according to claim 1, wherein the concentration of the mineral acid used is from 0.2 to 4.5 N to reduce the damage to the magnesium silicate. 3. The method according to claim 1, wherein the titration of the mineral acid used is a required equivalent calculated from the average impurity carbonate content in the magnesium silicate ore, and the titration speed is 1 / per minute or less of the required equivalent. Item 3. The method according to Item 2.