JPS6065703A - Production of high-purity chlorine dioxide - Google Patents

Abstract

PURPOSE:The reaction between a chlorate salt and MnCO3 or a divalent Mn compound in an acidic solution is followed by allowing ClO2 in the gas generated to be absorbed in the acidic solution whereby simultaneous production of high-purity ClO2 and MnO2 excellent in cell properties can be effected. CONSTITUTION:Air, an acidic solution of 0.1-20N and an chlorate salt solution are fed through lines 12-14 into the generating tank 11 in which MnCO3 or a divalent Mn compound containing its carbonate salt at least as a part and Mn oxide to effect the reactions at 25-70 deg.C, and the Mn oxide to which the MnO2 formed adheres is led into the separator 21 where the MnO2 is separated. The acidic solution is introduced into the crystallizer 42, then recycled through the line 15 to the tank 11. In the meantime, the gas generated in the tank 11 is introduced into the absorption column 41 where ClO2 is absorbed in the acidic solution and the remaining CO2 and air is exhausted through line 42 outside the system. Then, the ClO2 in the column 61 is eliminated by the air introduced from the line 63 and recovered through line 64.

Description

[Detailed Description of the Invention] The present invention reduces chlorate using a reducing agent and oxidizes it! In a method for producing tA element, high-purity tA element dioxide is safely and efficiently produced using manganese carbonate or a divalent manganese compound containing manganese carbonate as a reducing agent, and at the same time mancane dioxide, which is mainly useful as a battery material, is produced. It is about the method.

Chlorine dioxide is used as a pulp bleaching agent in large quantities and in large scale applications. It is also widely used in the fields of environmental protection and pollution prevention, such as decolorizing fats, removing diphenols from industrial waste, and denitrifying smoke. Furthermore, in recent years, chlorine has been used to disinfect water supplies, but the production of trihalomethanes, a carcinogen, due to chlorine treatment has become a problem. Chlorine dioxide, which does not generate trihalomethanes, is seen as a promising alternative to chlorine. However, since chlorine dioxide is in a gaseous state at room temperature and there is a risk of drying out, elemental dioxide #A is manufactured at the site of use. For this reason, there is a strong need for a method for producing high-purity chlorine dioxide in which chlorine dioxide can be generated safely and easily.

An example of chlorine dioxide chloride is produced by the chemical reaction formula (1) when sodium chlorate is treated with hydrochloric acid as a reducing agent.

Na0IO3-1-2HO1-+ 0101 +3≦O
1, -1-Mail 1110 - (Rimata (1)
Along with the reaction of the formula, a side reaction of the following formula (2) that does not produce chlorine dioxide occurs.

Na010. -1-6HO1-+ 301. -) Ma
il +5H,O- (2) Conventionally, formula (1) has been used to minimize the amount of chlorine produced in leg 1, but even if the reaction of formula (2) does not occur, the generation will be 66.7- It doesn't go beyond that. t fc One method for producing high-purity chlorine dioxide is to reduce sodium chlorate with sulfur dioxide gas, as described in JP-A-55-162404. This reaction is shown by equation (3), but because the reaction is slow, naolo3+3≦So@→0101+3≦
N62804 ++ (3) The conversion rate of ram and sulfur dioxide gas is low, and unreacted sulfur dioxide gas is converted into chlorine dioxide.
Reduce the temperature.

It also has many drawbacks, such as requiring complicated dispersion such as vaporizing sulfur dioxide gas and producing high-concentration exhaust acid.

Mankan dioxide is also particularly useful as a battery material.
It is widely used in manganese batteries, alkaline batteries, etc., and is also used in lithium batteries, which have been gaining attention as high-energy density batteries in recent years.

Currently, manganese dioxide is mainly used for batteries, but natural manganese dioxide has become difficult to obtain in recent years.
The economic efficiency of electrolytic mankan dioxide is being lost due to the rising cost of carbon dioxide.

For the reasons mentioned above, there is a strong need for an economical method for producing manganese dioxide that has excellent stain retention characteristics.

The purpose of the present invention is to safely and easily produce high-purity chlorine dioxide.
Another object of the present invention is to provide a method for simultaneously producing manganese dioxide that is inexpensive and has excellent battery characteristics.

The present inventors conducted various studies to achieve the above object, and as a result, they arrived at the present invention.

That is, the present invention provides a method for producing high-purity chlorine dioxide, in which a chlorate and a divalent manganese compound containing manganese carbonate or at least a part thereof as a carbonate are mixed in an acidic solution at 25C to 70C and a Wl concentration of 0. .The chlorine dioxide in the generated gas is absorbed into an acid solution by reacting at 1 to 20 normal, and the chlorine dioxide is diffused to simultaneously obtain high-purity chlorine dioxide and manka ytl dioxide. This is a method for producing high-purity chlorine dioxide.

More specifically, in the method of the present invention, mancane oxide is present in an acidic solution, and chlorate is reacted with a divalent manganese compound containing mancane carbonate or at least a part thereof as a carbonate. , the manganese oxide can be made heavier, and at the same time, the rate of generation of chlorine dioxide can be increased.

The manganese oxide used in the method of the present invention preferably has an atomic ratio of L manganese to oxygen of 1:1 to 2, and is more preferably an oxide obtained by roasting manganese carbonate.

The chlorate used in the method of the present invention is fcl selected from the group of sodium chlorate, potassium chlorate, tRm F lithium, calcium chlorate and magnesium chlorate, or a mixture of two or more thereof.

The divalent mancan compound used in the method of the present invention is one or more compounds selected from the group of mancan nitrate, manganese sulfate, mancan chloride, PG mancan, water [IS mancan and mancan monoxide]. It is a mixture.

@ in the acidic solution in the method of the present invention is nitric acid.

These are sulfuric acid, hydrochloric acid, #lI acid, and mixed acids thereof. ? I
When using t1 acid, the acid concentration for fc@ is in the range of 2N to 15N, and when using sulfuric acid, i! The concentration should be in the range of 5N to 18N, and when hydrochloric acid is used at 71C, the acid concentration is in the range of (L2N to 3N), and when common acid is used, the acid concentration is in the range of 3N to 18N, and When using a mixed acid, the acid concentration is in the range from the smallest lower limit concentration to the largest upper limit concentration of each h.
If the acid concentration is lower than the lower limit, the reaction will not proceed at a sufficient rate. Furthermore, if the concentration is higher than the upper limit concentration, the rate of generation of chlorine dioxide will increase significantly, creating a dangerous situation.

The reaction temperature in the method of the present invention is 25°C to 70°C.
Use. If it is less than 250, the reaction will not proceed at a sufficient rate. Moreover, at 70C or higher, the rate of generation of chlorine dioxide is extremely slow, which does not lead to a dangerous situation, but also causes a decrease in the conversion rate of chlorate to chlorine dioxide, that is, an increase in the basic unit of chlorine. Chlorine dioxide, which is normally produced, decomposes into chlorine and oxygen, sometimes resulting in plowing. Preferably 50C to 60
C The m solution in the method of the present invention is nitric acid, salt m, phosphoric acid, and mixed acids thereof. Its Wln degree is α01 specified to 2 PJl, constant. Below the a01 regulations (4
) and (5) reactions proceed at sufficient speed M
n0O1-1-21+-+ Mn”10H20+oo□↑
-(4)Mn"+20103-+Mno2+cto
2↑ ・(5) Don't do it. Also, even if there are 2 or more provisions, the effect will not be particularly swamped by 1.

One true embodiment of the method of the present invention will be explained with reference to the accompanying drawings. Manganese oxide and Rrt! are generated in WJ11.
A divalent manganese compound containing at least a part of manganese fcd as a carbonate is dispersed in water, and air is introduced through line 12. Line 15 with citric acid mother liquor or line 14 with citric acid.

In addition, aqueous solution of cyclochloride (i) was introduced into the main tank 11 through the line 15, and reactions were carried out from 1711 to 1'. The recombinant scum produced in the generator 11 and the chlorine dinitride air are removed in the gas phase, and the produced mankan dioxide is the mankan oxide that was previously added as a solid. The weight can be further increased by increasing the amount of manga dioxide produced by the reaction of formula (5).

The heavy manganese oxide is led to the manganese oxide separator 21 together with an acidic solution through a line 22, separated from the acidic solution, and removed from the system through a line 23, washed with water, neutralized, washed with water, dried, and then used for batteries. Used as manganese dioxide.

The heavy solution separated by the manganese oxide separator is led to the crystallization separator 31 through a line 32, and the salt consisting of the gold ion in the chlorate used and the P radical in the acidic solution is crystallized. It is crystallized by cooling or concentration in the separator 31 and removed through the line 53. Acidic mother liquor passes through line 15 to generation tank 1.
It is set back to 1.

, h raw material 41!11 is led to an absorption tower 41 together with carbon dioxide gas and chlorine dioxide gas. As shown in the figure, the absorption column 41 is connected to the purification column 51, the dispersion column 61fC, and the acid solution is circulated between each column through the 2-in 43. Upon contact with the acid solution, the carbon dioxide salt dissolves in the acid solution, and the carbon dioxide scum is removed from the system through line 42 along with air. The acid solution from the anus collection tower is routed to line 52.
Guided to uFi tower 51. Here, a small amount of air is introduced through the line 53, and slightly dissolved carbon dioxide is introduced into the line 53.
The purity of the chlorine dimide already dissolved in the acid solution is increased by dissipating it throughout the solution. 1? The acid solution from the J tower is led to the stripping tower 61 through the line 62, and air is introduced through the line 63 to diffuse the dissolved chlorine dioxide. Obtained from line 64. This chlorine dimide may be dissolved in cold water to form a chlorine dioxide aqueous solution, or may be absorbed into an alkaline solution containing hydrogen peroxide to form a hexachloride salt.

; In the conventional production method of chlorine dioxide,
3) As shown in the formula, the by-products are sodium chloride and sodium sulfate, which are of low value.By the method of the present invention, chlorine dioxide with a high H degree can be produced, and at the same time, it is useful as mankan dioxide for batteries. Since it is possible to obtain a heavy manganese 77/oxide, the production costs for both chlorine dioxide and mankan oxide can be significantly reduced.

Furthermore, the manganese oxide obtained according to the present invention showed superior battery bone properties to conventional electrolytic manganese dioxide. For example, mankan oxide obtained by decorating with manganese carbonate (Mn0.
90%, packing density 2.1 k) was present and reacted with sodium chlorate and manganese carbonate to obtain a heavy mankan oxide (95% Mn, packing density 2.3 k).

This 259 was assembled into a single type zinc chloride battery, and as a result of continuous discharge of 4 ohm, the result was 1.7v to o, asv-
The time it took for the temperature to drop to 1 was 23 hours. Further, electrolytic manganese dioxide (IC-1) was used for 18 hours.

Next, the present invention will be explained in detail by way of examples.

Example 1 Mankan oxide 1 obtained by roasting carbonated mankan
f, charcoal R-r linker/LIL12Kf and main fishing 2.
OK9 'i Karasuomotetsuro Frusu with an internal capacity of 5 tons: f
f (generated m) and add 98% sulfur rR0, while stirring.
6Btf: Gradually add % # once to expel carbonate scum and warm /, n r' br15L -4> 4NO
In? QlnJlk m1. , J ~ , -a41
, −+ −−−+ Rita. Next, while blowing air at a rate of "t/min, 650 V/1 sodium chloride aqueous solution was added for 542 t hours to generate carbon dioxide scum and carbon dioxide. The reaction was continued until divalent manganese ions disappeared. The first reaction was completed.The purity of the chlorine dioxide gas coming out of the chloric acid smut generation tank was 83%.The chlorine dioxide was absorbed into a 100% 0.1N sulfuric acid aqueous solution and evacuated with air. However, the purity of chlorine dioxide scum is 9
It was 7%. The heavy mankan oxide in the slurry in the generation tank was filtered out using a glass filter, washed with water, and dried to obtain 1.1 KF of heavy mankan oxide. This 25
When F was assembled into a single-cell zinc chloride battery and discharged across 4 ohms, it took 23 hours for the voltage to drop from 1.7V to 0.85V.

The acid in the reaction solution, the divalent mankan compound, the salt content and the concentration of the ρ solution for the absorption of divalent chlorine, the reaction temperature, and the result. It is shown in Table 1.

As shown in Table 1, when the reaction temperature is raised to aSC, the chlorate consumption rate becomes extremely high and the discharge characteristics also deteriorate. It is also easy to remove carbonate scum and dioxide salts in acid solution.

[Brief explanation of drawings]

FIG. 1 is a flow sheet showing one embodiment of the present invention. 11... Generation tank 21... Mankan oxide separator 31... Crystallization separator 41...
... Absorption tower 51 ... Purification tower 61 ...
Dispersion Tower Section 11 Procedures Amendment Written November 18, 1981 Kazuo Wakasugi, Director General of the Patent Office. 5, N8 Correct Contents of "Detailed Explanation" (1) "For alkaline batteries, etc." in line 4 of page 1 of the specification is corrected to "for alkaline batteries, etc." (2) “Formula (4) and (5)” on page 10, line 4 of the specification
"The reaction in equation (4) and (5) are proceeding at a sufficient speed" should be corrected to "separation of chlorine dioxide and carbon dioxide produced in equations (4) and (5) is insufficient." (3) Delete “No.J” on page 10, line 4 of the specification.

Claims (1)

[Claims] 1. A method for producing high purity chlorine dioxide. chlorate and manganese carbonate, a divalent manganese compound containing at least a part of it as carbonate, in an acidic solution with 25c to 7rJC and 11% degree 0.1 to 20
React according to the specified conditions, and remove the buried wood dioxide in the generated gas.
High-purity chlorine dioxide is collected into fc, and then the chlorine dioxide is diffused to obtain high-purity chlorine dioxide and mankan dioxide at the same time! R construction method. 2. The manufacturing method according to claim IJF4, characterized in that the reaction is carried out in the presence of manganese oxide in an acidic solution. &The atomic ratio of manganese oxide to mankan and WR element is 1:1.
4. The manufacturing method according to claim 2, wherein the manganese oxide is an oxide obtained by roasting manganese carbonate. 5. Chlorate is sodium chlorate, potassium chlorate, lithium chlorate, saltffi? The manufacturing method according to claim 1, wherein the manufacturing method is a mixture of one or more compounds derived from the group of calcium and magnesium chlorate. 6. The divalent mancan compound is selected from the group of manganese nitrate, ρ sulfur, manganese, manganese chloride, manganese manganese, manganese chloride, and manganese monoxide, and is a mixture of 7c1 or more. 232. The manufacturing method according to claim 231, characterized in that: Z What is the acid in the acidic solution? 2. The manufacturing method according to claim 1, which includes il'+ri, ffL, hydrochloric acid, phosphorus, and a mixture thereof. A patent characterized in that the acid concentration is preferably in the range of 2 to 15N for nitric acid, 3 to 18N for the number of volumes, and 0.2 to 6 for hydrochloric acid, from the smallest lower limit concentration to the largest upper limit concentration of each acid. The manufacturing method according to claim 1. 9. The production method according to claim 1, wherein the acid in the sulfuric acid solution is nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, or a mixed acid thereof. The production method according to claim 9, characterized in that the acid concentration of the 1α acid solution is (LOI standard to 2 normal). 11. A patent claim, characterized in that the reaction temperature is preferably 50C to SSC. 12. In the method for producing high-purity chlorine dioxide, a chlorate and a mankane carbonate or a divalent mankane compound containing mankane carbonate are mixed in an acidic solution at 250 to 60 C and [% The first step is to react at a temperature of α1 to 20 normal, the third step is to separate the obtained mankan dioxide, neutralize it and/or wash it with water, and dry it. i!! The third step consists of returning the acid-containing recovered solution from which the by-product salts from the roots have been separated and removed to the first step, and the salt dioxide water in the gas generated in the first step is absorbed into the acid solution. A method for producing high-purity chlorine dioxide, which comprises a fourth step of dissipating the chlorine dioxide after the reaction.A patent claim characterized in that the reaction is carried out in the presence of manganese oxide in a French acidic solution. The manufacturing method according to item 1.