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sodium chlorate
Sodium-chlorate-component-ions-2D.png
General
Systematic Name	sodium chlorate
Traditional names	sodium chloride
Chem. formula	NaClO 3
Physical properties
State	colorless crystals
Molar mass	106.44 g/mol
Density	2.490; 2.493 g/cm³
Thermal Properties
T. melt.	255; 261; 263°C
T. kip.	dec. 390°C
Mol. heat capacity	100.1 J/(mol K)
Enthalpy of formation	-358 kJ/mol
Chemical properties
Solubility in water	100.5 25; 204 100 g/100 ml
Solubility in ethylenediamine	52.8 g/100 ml
Solubility in dimethylformamide	23.4 g/100 ml
Solubility in monoethanolamine	19.7 g/100 ml
Solubility in acetone	0.094 g/100 ml
Classification
Reg. CAS number	7775-09-9
SMILES	Cl(=O)=O]
Reg. EC number	231-887-4
RTECS	FO0525000
Data is based on standard conditions (25 °C, 100 kPa) unless otherwise noted.

sodium chlorate- inorganic compound, sodium metal salt and chloric acid with the formula NaClO 3 , colorless crystals, highly soluble in water.

Receipt

• Sodium chlorate is prepared by the action of chloric acid on sodium carbonate:

$\backslash mathsf(Na\_2CO\_3\; +\; 2\backslash \; HClO\_3\backslash \; \backslash xrightarrow(\backslash \; )\backslash \; 2\backslash \; NaClO\_3\; +\; H\_2O\; +\; CO\_2\backslash uparrow\; )$

• or by passing chlorine through a concentrated sodium hydroxide solution when heated:

$\backslash mathsf(6\backslash \; NaOH\; +\; 3\backslash \; Cl\_2\backslash \; \backslash xrightarrow(\backslash \; )\backslash \; NaClO\_3\; +\; 5\backslash \; NaCl\; +\; 3\backslash \; H\_2O\; )$

• Electrolysis of aqueous solutions of sodium chloride:

$\backslash mathsf(6\backslash \; NaCl\; +\; 3\backslash \; H\_2O\; \backslash \; \backslash xrightarrow(e^-)\backslash \; NaClO\_3\; +\; 5\backslash \; NaCl\; +\; 3\backslash \; H\_2\backslash uparrow\; )$

Physical properties

Sodium chlorate - colorless cubic crystals, space group P 2 1 3 , cell parameters a= 0.6568 nm, Z = 4.

At 230-255°C it passes into another phase, at 255-260°C it passes into a monoclinic phase.

Chemical properties

• Disproportionates when heated:

$\backslash mathsf(10\backslash \; NaClO\_3\; \backslash \; \backslash xrightarrow(390-520^oC)\backslash \; 6\backslash \; NaClO\_4\; +\; 4\backslash \; NaCl\; +\; 3\backslash \; O\_2\backslash uparrow\; )$

• Sodium chlorate is a strong oxidizing agent; in the solid state, mixed with carbon, sulfur and other reducing agents, it detonates when heated or on impact.

Application

• Sodium chlorate has found application in pyrotechnics.

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Literature

• Chemical Encyclopedia / Ed.: Knunyants I.L. and others. - M .: Soviet Encyclopedia, 1992. - T. 3. - 639 p. - ISBN 5-82270-039-8.
• Handbook of a chemist / Editorial board: Nikolsky B.P. and others. - 2nd ed., corrected. - M.-L.: Chemistry, 1966. - T. 1. - 1072 p.
• Handbook of a chemist / Editorial board: Nikolsky B.P. and others. - 3rd ed., corrected. - L.: Chemistry, 1971. - T. 2. - 1168 p.
• Ripan R., Chetyanu I. Inorganic chemistry. Chemistry of metals. - M .: Mir, 1971. - T. 1. - 561 p.

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An excerpt describing sodium chlorate

It was eleven o'clock in the morning. The sun stood somewhat to the left and behind Pierre and brightly illuminated through the clean, rare air the huge panorama that opened before him like an amphitheater along the rising terrain.
Up and to the left along this amphitheater, cutting through it, the great Smolenskaya road wound, going through a village with a white church, lying five hundred paces in front of the mound and below it (this was Borodino). The road crossed under the village across the bridge and through the descents and ascents wound higher and higher to the village of Valuev, which could be seen six miles away (Napoleon was now standing in it). Behind Valuev, the road was hidden in a yellowed forest on the horizon. In this forest, birch and spruce, to the right of the direction of the road, a distant cross and the bell tower of the Kolotsky Monastery glittered in the sun. Throughout this blue distance, to the right and left of the forest and the road, in different places one could see smoking fires and indefinite masses of our and enemy troops. To the right, along the course of the Kolocha and Moskva rivers, the area was ravine and mountainous. Between their gorges, the villages of Bezzubovo and Zakharyino could be seen in the distance. To the left, the terrain was more even, there were fields with grain, and one could see one smoking, burned village - Semenovskaya.
Everything that Pierre saw to the right and to the left was so indefinite that neither the left nor the right side of the field fully satisfied his idea. Everywhere there was not a share of the battle that he expected to see, but fields, clearings, troops, forests, smoke from fires, villages, mounds, streams; and no matter how much Pierre disassembled, he could not find positions in this living area and could not even distinguish your troops from the enemy.
“We must ask someone who knows,” he thought, and turned to the officer, who was looking with curiosity at his unmilitary huge figure.
“Let me ask,” Pierre turned to the officer, “which village is ahead?”
- Burdino or what? – said the officer, addressing his comrade with a question.
- Borodino, - correcting, answered the other.
The officer, apparently pleased with the opportunity to talk, moved towards Pierre.
Are ours there? Pierre asked.
“Yes, and the French are farther away,” said the officer. “There they are, they are visible.
- Where? where? Pierre asked.
- You can see it with the naked eye. Yes, here, here! The officer pointed with his hand at the smoke visible to the left across the river, and on his face appeared that stern and serious expression that Pierre had seen on many faces he met.
Oh, it's French! And there? .. - Pierre pointed to the left at the mound, near which troops were visible.
- These are ours.
- Ah, ours! And there? .. - Pierre pointed to another distant mound with a large tree, near the village, visible in the gorge, near which fires were also smoking and something blackened.
"It's him again," the officer said. (It was the Shevardinsky redoubt.) - Yesterday was ours, and now it's his.
So what is our position?
- Position? said the officer with a smile of pleasure. - I can tell you this clearly, because I built almost all of our fortifications. Here, you see, our center is in Borodino, right here. He pointed to a village with a white church in front. - There is a crossing over the Kolocha. Here, you see, where rows of cut hay lie in the lowlands, here is the bridge. This is our center. Our right flank is where (he pointed steeply to the right, far into the gorge), there is the Moskva River, and there we built three very strong redoubts. The left flank ... - and then the officer stopped. - You see, it's hard to explain to you ... Yesterday our left flank was right there, in Shevardin, over there, you see where the oak is; and now we have taken back the left wing, now out, out - see the village and the smoke? - This is Semenovskoye, yes here, - he pointed to the mound of Raevsky. “But it’s unlikely that there will be a battle here. That he moved troops here is a hoax; he, right, will go around to the right of Moscow. Well, yes, wherever it is, we will not count many tomorrow! the officer said.
The old non-commissioned officer, who approached the officer during his story, silently waited for the end of his superior's speech; but at this point he, obviously dissatisfied with the words of the officer, interrupted him.
“You have to go for tours,” he said sternly.
The officer seemed to be embarrassed, as if he realized that one could think about how many people would be missing tomorrow, but one should not talk about it.
“Well, yes, send the third company again,” the officer said hastily.
“And what are you, not one of the doctors?”

The invention relates to the production of sodium chlorate, widely used in various industries. The electrolysis of sodium chloride solution is carried out first in chlorine diaphragm cells. The resulting chloride-alkali solutions and electrolytic chlorine gas are mixed to form a chloride-chlorate solution. The resulting solution is mixed with the mother liquor of the crystallization stage and sent to non-diaphragm electrolysis, followed by evaporation of chloride-chlorate solutions and crystallization of sodium chlorate. The products of diaphragm electrolysis can be partly diverted to obtain hydrochloric acid from chlorine gas for acidification of chlorate electrolysis and the use of chloride-alkali solutions for irrigation of sanitary columns. The technical result is a reduction in power consumption and the possibility of organizing autonomous production. 1 z.p.f.

The invention relates to the production of sodium chlorate, widely used in various industries. World production of sodium chlorate reaches several hundred thousand tons per year. Sodium chlorate is used to produce chlorine dioxide (bleach), potassium chlorate (Bertolet salt), calcium and magnesium chlorates (defoliants), sodium perchlorate (an intermediate for the production of solid rocket fuel), in metallurgy during the processing of uranium ore, etc. A known method for producing sodium chlorate by a chemical method, in which sodium hydroxide solutions are subjected to chlorination to obtain sodium chlorate. According to its technical and economic indicators, the chemical method cannot compete with the electrochemical method, therefore, it is practically not used at present (L.M. Yakimenko "Production of chlorine, caustic soda and inorganic chlorine products", Moscow, from "Chemistry", 1974, p. .366). A known method for producing sodium chlorate by electrolysis of a sodium chloride solution in a cascade of non-diaphragm electrolyzers to obtain chloride-chlorate solutions, from which crystalline sodium chlorate is isolated by evaporation and crystallization (K. Wihner, L. Kuchler "Chemische Technologie", Bd.1, "Anorganische Technologie", s.729, Munchen, 1970; L.M. Yakimenko, T. A. Seryshev "Electrochemical synthesis of inorganic compounds, Moscow, "Chemistry", 1984, pp. 35-70). This method is the closest The main technological stage, diaphragmless electrolysis of sodium chloride solutions, proceeds with a current output of 85-87%. hydrochloric acid.Before entering the stage of separation of the solid product, the electrolyte is alkalinized to an excess of alkali of 1 g/l with the addition of a reducing agent to destroy the corrosive sodium hypochlorite, always present in the products of electrolysis. A side anode process in the electrolysis of chloride solutions is the release of Cl 2 , which not only reduces the current efficiency, but also requires the purification of electrolysis gases in sanitary columns irrigated with an alkali solution. The implementation of the process is therefore associated with a significant consumption of hydrochloric acid and alkali: 1 ton of sodium chlorate consumes ~120 kg of 31% hydrochloric acid and 44 kg of 100% NaOH. For the same reason, chlorate production is organized where there is chlorine electrolysis, which supplies caustic soda and electrolytic chlorine and hydrogen for the synthesis of hydrochloric acid, while there is often a need for autonomous production of sodium chlorate at points remote from chlorine production. But even where chlorine production and chlorate electrolysis are located nearby, when chlorine electrolysis is stopped and turned off for one reason or another, a forced shutdown of chlorate electrolysis occurs. Thus, the known method has significant drawbacks: high energy costs (not very high current efficiency ) and the impossibility of organizing autonomous production. The objective of the invention is to create a method for producing sodium chlorate by electrolysis of sodium chloride solutions with reduced energy costs. The problem is solved by the proposed method, in which sodium chloride is first processed in chlorine diaphragm electrolyzers to produce gaseous chlorine gas and electrolytic lye compositions of 120-140 g/l NaOH and 160-180 g/l NaCl, which are then fully or partially subjected to interaction between itself with obtaining a chloride-chlorate solution of 50-60 g/l NaClO 3 and 250-270 g/l NaCl, sent to bezdiaphragm electrolysis. The process of chlorate non-diaphragm electrolysis is carried out by acidification with hydrochloric acid. The resulting chlorate solution, which also contains sodium chloride, is sent to the stage of evaporation, and then crystallization of the chlorate. The mother liquor from the crystallization stage, together with the products of the interaction of alkali and chlorine from diaphragm electrolysis, is sent to non-diaphragm chlorate electrolysis. Before entering the stage of isolation of the solid product, the electrolyte is alkalinized to an excess of alkali of 1 g/l with the addition of a reducing agent to destroy sodium hypochlorite. With partial withdrawal of electrolysis products from chlorine diaphragm electrolyzers, chlorine is used to produce hydrochloric acid, which is used to acidify chlorate electrolysis, and alkali is used to irrigate sanitary columns during the purification of electrolysis gases. With this scheme, 30-35 g of sodium chloride out of 300-310 g contained in each liter of the initial solution is processed under the conditions of chlorine electrolysis. Such a scheme causes a reduction in energy costs, because. the current efficiency of chlorine electrolysis is higher, and the voltage on the electrolyzers is lower than in chlorate electrolysis, and when partially electrochemically oxidizing sodium chloride to chlorate under conditions of chlorine electrolysis, the performance of the whole process improves. In addition, when using the described scheme, the cost of electrolysis cooling is reduced, since chlorine electrolyzers do not need cooling. Note that a deeper activation of chloride under the conditions of chlorine electrolysis than specified (about 10%) leads to the impossibility of balancing the technological scheme for chlorides, chlorates and water and therefore does not make sense. Within the framework of the proposed scheme, it is possible to obtain an additional effect when applying solutions with an increased NaClO 3 concentration to chlorate electrolysis, obtained from alkali solutions more concentrated in NaOH than diaphragm lye, for the chlorination of which chlorine containing inerts can be utilized. Electrolytic chlorine electrolysis can be mixed with chlorine gas not completely, but partially. At the same time, part of the electrolytic lye from diaphragm electrolysis, not directed to chlorination, is diverted for use in sanitary columns, and the equivalent part of electrolytic chlorine can be used for the synthesis of hydrochloric acid. The direction of electrolytic alkalis from diaphragm electrolyzers to sanitary columns, and electrolytic chlorine gas to produce hydrochloric acid solves the problem of autonomous chlorate production, since the supply of alkali and acid from outside will no longer be required. The proportion of sodium chloride processed in chlorine electrolyzers is determined by whether the resulting products will be used only to obtain chloride-chlorate liquors as a result of their interaction, after mixing with the mother liquor from the crystallization stage to non-diaphragm electrolysis, or the electroliquor of chlorine electrolyzers will be used only for alkalization, and electrolytic chlorine - for the synthesis of perchloric acid for acidification in the chlorate electrolysis circuit, or part of the products will be used in one direction, and part in another. The advantages of the proposed method are: 1) reduction of energy costs due to the initial stage of electrolysis with a high current output and at a lower voltage than in conventional chlorate electrolysis: current output 92-94% and voltage 3.2 V in chlorine electrolysis versus 85 -90% and 3.4 V and above, respectively, in chlorate; 2) the possibility of obtaining simultaneously with the main product - sodium chlorate - alkaline solutions required by the technological scheme for alkalization and irrigation of sanitary columns; 3) the possibility of using chlorine produced in chlorine electrolyzers to produce hydrochloric acid in situ for acidification of chlorate electrolysis. Example In an experimental cell, chlorine diaphragm electrolysis of a sodium chloride solution with a concentration of 300 g/l is carried out on ruthenium oxide anodes at a current density of 1000 A/m 2 and a temperature of 90 o C. The resulting electrolytic liquors containing 140 g/l NaOH and 175 g/l NaCl, mixed with anode chlorine gas and receive chloride-chlorate solution composition of 270 g/l NaCl and 50 g/l NaClO 3 . This solution is then fed to a non-diaphragm chlorate electrolysis carried out in a cascade of 4 electrolyzers with ruthenium oxide anodes at a current density of 1000 A/m 2 and a temperature of 80 o C to obtain a final solution of the following composition: 105 g/l NaCl and 390 g/l NaClO 3 . Thus, from one 1 liter of the initial chloride solution, taking into account a 10% decrease in the volume of the solution due to the entrainment of water vapor with electrolysis gases and the evaporation of 355 g of sodium chlorate, of which 50 g (14.1%) was obtained after mixing the products of chlorine diaphragm electrolysis , and 305 (85.9%) were produced in the process of chlorate electrolysis. The voltage across the chlorine cell was 3.3 V with a current output of 93%. The average voltage across the chlorate cell was 3.4 V with a current output of 85%. Specific power consumption W (kWh/t) calculated according to the experimental data using the formula W = 1000E/mBT, where E is the cell voltage (B); m - electrochemical equivalent (g/Ah); BT - current output in fractions of a unit,
amounted to 2517 kWh / t for chlorine electrolysis, and 5996 kWh / t for chlorate electrolysis, which, taking into account the share of chlorate produced as a result of mixing chlorine electrolysis products, gives 5404.9 kWh / t. Electricity consumption without the use of a chlorine electrolyzer was 6150 kWh/t at the same plant. Thus, the reduction in energy costs amounted to 12.1%.

Claim

1. A method for producing sodium chlorate by electrolysis of a sodium chloride solution, followed by evaporation of chloride-chlorate solutions and crystallization of sodium chlorate with the return of the mother liquor of the crystallization stage to the process, characterized in that first the electrolysis of a solution of sodium chloride is carried out in chlorine diaphragm electrolyzers to obtain alkali-chloride solutions and electrolytic chlorine gas, which are mixed to obtain a chloride-chlorate solution and sent after mixing with the mother liquor of the crystallization stage to non-diaphragm electrolysis. 2. The method according to claim 1, characterized in that the products of diaphragm electrolysis are partly removed to obtain hydrochloric acid from chlorine gas for acidification of chlorate electrolysis and the use of chloride-alkali solutions for irrigation of sanitary columns.

Sodium perchlorate is a colorless and odorless crystalline substance. It is hygroscopic and forms several crystalline hydrates. From a chemical point of view, it is the sodium salt of perchloric acid. Not combustible, but has a toxic effect. The chemical formula of sodium perchlorate is NaClO 4 .

Receipt

The described substance can be obtained both chemically and electrochemically. In the first case, the usual exchange reaction between perchloric acid and sodium hydroxide or carbonate is usually used. Thermal decomposition of sodium chlorate is also possible. At 400-600 °C, it forms perchlorate and sodium chloride. But this method is quite dangerous, since there is a threat of an explosion during the reaction.

Theoretically, it is possible to carry out chemical oxidation of sodium chlorate. The most effective oxidizing agent in this case will be lead (IV) oxide in an acidic environment. Typically, perchloric acid is added to the reaction mixture.

Most often in industry, the electrochemical method is used. It gives a cleaner product, and is generally more effective. The same sodium chlorate is used as a raw material, which, when oxidized on a platinum anode, gives perchlorate. For the economy of the process, sodium chlorate is obtained on cheaper electrodes such as graphite. There is also a promising method for obtaining sodium perchlorate in one stage. Lead peroxide is used as an anode.

Mechanisms for electrochemical production

The mechanism of the oxidation of chlorate to perchlorate has not yet been fully studied; there are only assumptions about it. Research is still ongoing.

The most reasonable option is based on the assumption of electron donation at the anode of the chlorate ion (ClO 3 -), which results in the formation of the ClO 3 radical. It, in turn, reacts with water, forming perchlorate.

This assumption is expressed in a number of authoritative scientific papers. It is also confirmed by the results of studies of the processes of oxidation of chlorates to perchlorates in aqueous solutions labeled with heavy oxygen isotopes 18 O. It was found that 18 O is first included in the composition of the chlorate and only then, during the oxidation process, passes into the composition of the perchlorate ion. But it must be taken into account that changing the anode material (for example, from platinum to graphite) can also change the reaction mechanism.

The second variant of the process flow consists in the oxidation of chlorate ions with oxygen, which is formed when electrons are donated by the hydroxide ion.

According to this variant, the reaction rate directly depends on the concentration of chlorate in the electrolyte, i.e., with a decrease in its concentration, the rate should increase.

There is also a variant based on the simultaneous donation of electrons by both the chlorate ion and the hydroxide ion. The radicals formed as a result of reactions are highly active and are oxidized by oxygen, which is released from OH - .

Physical properties

Sodium perchlorate is very soluble in water. Its solubility is much stronger than other perchlorates. For this reason, in the production of perchlorates, sodium perchlorate is first obtained, and then, if necessary, it is converted into other salts of perchloric acid. It is also highly soluble in liquid ammonia, acetone, hydrogen peroxide, ethanol and ethylene glycol.

As mentioned above, it is hygroscopic, and upon hydrolysis, sodium perchlorate forms crystalline hydrates (mono- and dihydrates). It can also form solvates with other compounds. At a temperature of 482 ° C, it melts with decomposition into sodium chloride and oxygen. When using additives of sodium peroxide, manganese (IV) oxide, cobalt (II, III) oxide, the decomposition temperature drops to 150-200 °C.

Chemical properties

The sodium salt of perchloric acid is a very strong oxidizing agent, so much so that it oxidizes many organic substances to carbon dioxide and water.

The perchlorate ion can be detected by reacting with ammonium salts. When the mixture is calcined, the reaction proceeds:

3NaClO4 + 8NH 4 NO 3 → 3KCl + 4N 2 + 8HNO 3 + 12H 2 O.

Another detection method is an exchange reaction with potassium. Potassium perchlorate is much less soluble in water, so it will precipitate out.

NaClO 4 + KCl → KClO 4 ↓ + NaCl.

It can form complex compounds with other perchlorates: Na 2 , Na, Na.

Application

Due to the formation of crystalline hydrates, the use of sodium perchlorate is extremely difficult. It is mainly used as a herbicide, although recently it has become less and less. Almost all sodium perchlorate is converted into other perchlorates (for example, potassium or ammonium) or perchloric acid and is used in the synthesis of many other compounds due to its strong oxidizing properties. It can also be used in analytical chemistry for the determination and precipitation of potassium, rubidium and cesium cations, both from aqueous and alcoholic solutions.

The thermal decomposition of all perchlorates releases oxygen. Due to this, salts can be used as a source of oxygen in rocket engines. Some perchlorates can be used in explosives. Potassium perchlorate is used in medicine to treat hyperthyroidism. This disease is caused by an increased function of the thyroid gland, and any perchlorate has the ability to reduce the activity of this gland, which is necessary to bring the body back to normal.

Danger

Sodium perchlorate itself is non-flammable, but it can cause a fire or explosion if it interacts with certain other substances. In a fire, it may release toxic gases or vapors (chlorine or chlorine oxides). Extinguishing can be done with water.

Sodium perchlorate practically does not evaporate at room temperature, but when it is sprayed, it can enter the body. When inhaled, it causes coughing, irritation of the mucous membranes. Redness appears on contact with the skin. As a first aid, it is recommended to wash the affected area with copious amounts of soap and water, and to get rid of contaminated clothing. With prolonged exposure to the body, it enters the bloodstream and leads to the formation of methemoglobin.

When animals (particularly rodents) were injected with 0.1 g of sodium perchlorate, their reflex excitability increased, convulsions and tetanus appeared. After administration of 0.22 g, the rats died after 10 hours. When the same dose was administered to pigeons, they developed only mild symptoms of poisoning, but after 18 hours they died. This suggests that administration of sodium perchlorate develops very slowly.

GOST 12257-93

Group L17

INTERSTATE STANDARD

SODIUM CHLORATE TECHNICAL

Specifications

Sodium chlorate for industrial use. Specifications

OKP 21 4722

Introduction date 1996-01-01

Foreword

1 DEVELOPED MTK 89

INTRODUCED by Gosstandart of Russia

2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (minutes N 3-93 dated February 17, 1993)

Voted to accept:

State name	Name of the national standardization body
Republic of Azerbaijan	Azgosstandart
Republic of Armenia	Armstate standard
Republic of Belarus	Belstandard
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
Turkmenistan	Turkmengosstandart
The Republic of Uzbekistan	Uzgosstandart
Ukraine	State Standard of Ukraine

3 By Resolution of the Committee of the Russian Federation for Standardization, Metrology and Certification of December 23, 1994 N 349, the interstate standard GOST 12257-93 "Technical sodium chlorate. Specifications" was put into effect directly as a state standard of the Russian Federation from January 1, 1996.

4 INSTEAD OF GOST 12257-77

1 AREA OF USE

1 AREA OF USE

This standard applies to technical sodium chlorate (sodium chlorate), intended for the production of magnesium chlorate, high-performance oxidizers and bleaching compounds.

Formula NaClO.

Relative molecular weight (according to international relative atomic masses 1987) - 106.44.

2 REGULATORY REFERENCES

This standard uses references to the following standards:

GOST 12.1.007-76 SSBT. Harmful substances. Classification and general safety requirements

GOST 1770-74 Measuring laboratory glassware. Cylinders, beakers, flasks, test tubes. Specifications

GOST 2517-85 Oil and oil products. Sampling methods

GOST 2603-79 Reagents. Acetone. Specifications

GOST 3118-77 Reagents. Hydrochloric acid. Specifications

GOST 4148-78 Reagents. Iron (II) sulfate 7-water. Specifications

GOST 4204-77 Reagents. Sulfuric acid. Specifications

GOST 4212-76 Reagents. Preparation of solutions for colorimetric and nephelometric analysis

GOST 4220-75 Reagents. Potassium dichromate. Specifications

GOST 4517-87 Reagents. Methods for the preparation of auxiliary reagents and solutions used in the analysis

GOST 5044-79 Thin-walled steel drums for chemical products. Specifications

GOST 6552-80 Reagents. Phosphoric acid. Specifications

GOST 6709-72 Reagents. Distilled water. Specifications

GOST 7313-75 Enamels XB-785 and varnish XB-784. Specifications

GOST 9078-84 Flat pallets. General specifications

GOST 9147-80 Laboratory porcelain glassware and equipment. Specifications

GOST 9557-87 Flat wooden pallet 800x1200 mm in size. Specifications

GOST 9570-84 Box and rack pallets. General specifications

GOST 10555-75 Reagents and highly pure substances. Colorimetric methods for determining the content of iron impurities

GOST 10671.5-74 Reagents. Methods for determining impurities of sulfates

GOST 10931-74 Reagents. Sodium molybdate 2-aqueous. Specifications

GOST 14192-77 * Cargo marking
________________
GOST 14192-96

GOST 17811-78 Polyethylene bags for chemical products. Specifications

GOST 19433-88 Dangerous goods. Classification and labeling

GOST 20490-75 Reagents. Potassium permanganate. Specifications

GOST 21650-76 Means of fastening packaged cargoes in overpacks. General requirements

GOST 24104-88 * Laboratory scales for general purposes and exemplary. General specifications
________________
* On the territory of the Russian Federation, GOST R 53228-2008 applies, hereinafter in the text. - Database manufacturer's note.

GOST 24597-81 Packages of packaged goods. Main parameters and dimensions

GOST 26663-85 Transport packages. Formation using packaging tools. General technical requirements

GOST 27025-86 Reagents. General guidelines for testing

GOST 29169-91 Laboratory glassware. Pipettes with one mark

GOST 29208.1-91 Technical sodium chlorate. Method for determining the mass fraction of substances insoluble in water

GOST 29208.2-91 Technical sodium chlorate. Weight method for determining moisture

GOST 29208.3-91 Technical sodium chlorate. Mercurimetric method for determining the mass fraction of chloride

GOST 29208.4-91 Technical sodium chlorate. Titrimetric method for determining the mass fraction of chlorate using bichromate

GOST 29228-91 Graduated pipettes. Part 2: Graduated pipettes without set waiting time

GOST 29252-91 Burettes. Part 2: Burettes without waiting time

3 TECHNICAL REQUIREMENTS

3.1 Technical sodium chlorate must be produced in accordance with the requirements of this standard according to the technological regulations approved in the prescribed manner.

3.2 Technical sodium chlorate is produced in solid (fine-crystalline powder from white to yellow) and liquid (solution or pulp) form.

3.3 Liquid sodium chlorate is produced in two grades A and B.

Grade A sodium chlorate is used to produce chlorine dioxide using a waste-free method, grade B is used to produce magnesium chlorate, highly effective oxidizing agents and bleaching compounds.

3.4 In terms of chemical indicators, technical sodium chlorate must comply with the requirements and standards specified in Table 1.


Table 1

Name of indicator	Norm for sodium chlorate
	solid OKP 21 4722 0100
		brand A OKP 21 4722 0300	brand B OKP 21 4722 0400
1 Mass fraction of sodium chlorate, %, not less than
2 Mass fraction of water, %, no more		Not standardized
3 Mass fraction of chlorides in terms of NaCl, %, no more
4 Mass fraction of sulfates (SO),%, no more
5 Mass fraction of chromates (СrО), %, max
6 Mass fraction of substances insoluble in water, %, no more
7 Mass fraction of iron (Fe), %, no more
Note - The rates of impurities in a liquid product are given in terms of a 100% product

3.5 Marking

3.5.1 Special stencils must be applied to the tank in accordance with the rules for the carriage of goods in force in railway transport, part 2, section 41, 1976.

3.5.2. Transport marking - in accordance with GOST 14192 with the application of handling signs "Sealed packaging" on drums, "Keep away from heat" on bags.

3.5.3 Marking characterizing the transport hazard of the cargo - in accordance with GOST 19433 with a hazard sign corresponding to the classification code 5112 (class 5, subclass 5.1, drawing number 5), serial number UN 1495 for a solid product and 2428 for a liquid product.

3.5.4 The marking characterizing the packaged products must contain:

- Product name;



- gross and net weight (for bags - only net weight);



A deviation of ±2% of the actual weight from the nominal weight indicated in the marking is allowed.

3.6 Packaging

Solid sodium chlorate is packed in liners made of polyethylene film with a thickness of at least 0.100 mm, enclosed: in drums according to GOST 5044 made of galvanized steel of version B with a hatch diameter of 300 mm or version C with a capacity of 50-100 dm3 or drums painted inside and outside with perchlorovinyl varnish according to GOST 7313; in polyethylene bags M10-0.220 according to GOST 17811, enclosed in bags of chlorine fabric or fire-resistant textile bags.

Liner bags, bags made of chlorinated fabric and fire-resistant textile bags are manufactured according to normative and technical documentation approved in the prescribed manner.

By agreement with the consumer, it is allowed to pack solid sodium chlorate in polyethylene bags M10-0.220 in accordance with GOST 17811.

Polythene bags are sealed. Chlorine and fire-resistant bags are sewn up by machine, without capturing the plastic bag.

Product weight in a bag - (50±1) kg.

It is not allowed to get solid sodium chlorate between polyethylene and fabric bags, as well as on the outer surface of the container.

4 SAFETY AND ENVIRONMENTAL REQUIREMENTS

4.1 Sodium chlorate is toxic. Once in the human body, it causes the breakdown of red blood cells, vomiting, gastrointestinal disorders, and kidney damage. The maximum permissible concentration in the water of reservoirs for sanitary water use is 20 mg / dm, in the air of the working area 5 mg / m (3rd hazard class according to GOST 12.1.007).

4.2 Sodium chlorate is a strong oxidizing agent.

4.3 Sodium chlorate is a non-flammable explosive substance. When heated to a temperature exceeding the melting point (255 ° C), it begins to decompose. At temperatures above 600 °C, decomposition is accompanied by the release of oxygen and may cause an explosion. Mixtures of the product with combustible substances and mineral acids are explosive and may ignite spontaneously due to temperature rise, impact and friction.

4.4 Production facilities must be equipped with supply and exhaust ventilation. Equipment, pipelines, fittings must be airtight. Sampling points and dusty units should be equipped with local exhausts. Appropriate equipment and pipelines must be protected from static electricity and made in an explosion-proof design.

4.5 For personal protection of personnel, special clothing should be used in accordance with standard standards and individual respiratory and eye protection: gas mask grade B or BKF, respirator (when working with solid sodium chlorate), goggles.

4.6 If the product gets on clothing, it must be changed immediately. From the skin and mucous membranes, sodium chlorate is washed off with soap and water or baking soda. If sodium chlorate is ingested, induce vomiting, rinse the stomach and provide medical assistance. Washing of special clothes should be carried out after each shift.

4.7 In case of spillage of a liquid product or spillage of a solid product, it is necessary to collect it with a vinyl plastic or titanium scoop in a bucket of vinyl plastic or titanium and wash the place of spillage or spillage with water. Use a tool made of non-sparking material to remove the product.

4.8 Room cleaning wet or vacuum.

4.9 In case of fire, extinguish with water.

4.10 Solid wastes are to be burned in a special area outside the plant. Liquid waste is directed to the neutralization of wastewater and to the sewerage of chemically contaminated effluents. Gas emissions are diluted with an inert gas, cleaned of chlorine and released into the atmosphere.

5 ACCEPTANCE

5.1 Sodium chlorate is taken in batches. A batch is considered a quantity of a product that is homogeneous in terms of its quality indicators, accompanied by one quality document, or each tank.

The quality document must contain:

- name of the manufacturer and (or) its trademark;

- name of the product, its brand (for a liquid product);

- batch number and date of manufacture;

- the number of containers in the party;

- gross and net weight;

- classification code of the group according to GOST 19433;

- the results of the analyzes performed or confirmation of the compliance of the quality of sodium chlorate with the requirements of this standard;

- designation of this standard.

5.2 The manufacturer determines the mass fraction of sulfates at the request of the consumer.

5.3 To check the conformity of the quality of the product with the requirements of this standard, the sample size of the product is 10% of packaging units, but not less than three units or each tank.

5.4 Upon receipt of unsatisfactory results of the analysis, at least for one of the indicators, re-analysis is carried out on a doubled sample or a newly selected sample from the tank.

The results of the reanalysis apply to the entire lot.

6 METHODS OF ANALYSIS

6.1 Sampling

6.1.1 Spot samples of solid sodium chlorate are taken with a non-ferrous metal probe, immersing it to 2/3 of the depth of the drum or bag along the vertical axis. Scoop sampling from the flow is allowed. The mass of the incremental sample must be at least 200 g.

6.1.2 Samples are taken from the tank according to GOST 2517. In this case, before sampling, liquid sodium chlorate is heated and mixed. The heating temperature should be between 60 and 80 °C. The volume of the incremental sample must be at least 1 dm3.

6.1.3 Point samples are combined together, mixed and an average sample of a solid product weighing at least 250 g is taken, a liquid product - with a volume of at least 0.5 dm3. An average sample of the product is placed in a clean, dry glass jar with a ground stopper or a polyethylene jar with a screw cap. It is allowed to place an average sample of a solid product in a bag of polyethylene film, which is sealed.

A label is attached to the jar or package indicating the name of the product (its brand), batch number (tank), date of sampling and the name of the person who took the sample.

6.2 Liquid sample preparation

Before analysis, a sample of a liquid product is heated to a temperature of (80 ± 5) ° C and placed in pre-weighed cups for weighing in accordance with GOST 25336. The cups are closed, cooled and weighed again to determine the weight of the sample of the liquid product.

6.3 General instructions for the analysis - according to GOST 27025.

It is allowed to use other measuring instruments with metrological characteristics and equipment with technical characteristics not worse, as well as reagents in quality not lower than those indicated.

Rounding analysis results to the decimal point indicated in the specification table.

6.4 Determination of the mass fraction of sodium chlorate

6.4.1 Apparatus

Laboratory scales of the 2nd accuracy class according to GOST 24104 with the maximum weighing limit of 200 g.

Burette according to GOST 29252 with a capacity of 50 cm3.

Volumetric flask according to GOST 1770 version 1 or 2 with a capacity of 500 ml.

Conical flask type Kn according to GOST 25336 version 1 or 2 with a capacity of 250 ml.

Pipette according to GOST 29228 with a capacity of 10 cm.

Pipette according to GOST 29169 with a capacity of 10 and 25 cm.

Cup for weighing according to GOST 25336

6.4.2 Reagents

Distilled water according to GOST 6709.

Iron (II) sulfate, 7-water according to GOST 4148, a solution of molar concentration (FeSO 7HO) \u003d 0.1 mol / dm, is prepared as follows: 28 g of iron sulfate is dissolved in 500 cm3 of water, to which 100 cm3 of concentrated sulfuric acid. It is then diluted with water to 1 dm and, if necessary, filtered.

Potassium permanganate according to GOST 20490, solution of molar concentration (KMnO) = 0.1 mol / dm, prepared according to GOST 25794.2.

Orthophosphoric acid according to GOST 6552.

Sulfuric acid according to GOST 4204.

Sodium molybdate according to GOST 10931, solution with a mass fraction

6.4.3 Conducting analysis

1.3-1.7 g of the solid or 2.5 cm of liquid product prepared according to 4.2 is weighed, recording the weighing result in grams to four decimal places. A portion of the product is quantitatively transferred into a volumetric flask, dissolved in water, the volume of the solution in the flask is adjusted to the mark with water and mixed.

10 cm3 of the resulting solution is transferred with a pipette into a conical flask, then 25 cm3 of a solution of ferrous sulfate, 6 cm3 of sulfuric acid, 5 cm3 of orthophosphoric acid, 3-5 drops of a solution of sodium molybdate are added with a pipette, the contents of the flask are mixed and titrated with a solution of potassium permanganate until a faint pink color .

At the same time, a control experiment is carried out under the same conditions with the same volumes of reagents.

6.4.4 Handling results

Mass fraction of sodium chlorate, %, is calculated by the formula

where is the volume of a solution of potassium permanganate with a molar concentration of exactly 0.1 mol / dm, used for titration in the control experiment, cm;

- the volume of a solution of potassium permanganate with a molar concentration of exactly 0.1 mol / dm, used for titration of the sample, cm;

0.001774 - mass of sodium chlorate corresponding to 1 cm3 of a solution of potassium permanganate with a molar concentration of exactly 0.1 mol / dm, g;

- mass of the sample of the product (for a solid product in terms of dry matter), g.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.3% with a confidence level of 0.95.

Permissible absolute total error of the analysis result is ±0.9% (for a solid product) and ±0.5% (for a liquid product) with a confidence level of 0.95.

It is allowed to determine the mass fraction of sodium chlorate in accordance with GOST 29208.4. When analyzing a liquid product, a 5 cm sample is taken, prepared

6.5 Determination of the mass fraction of water

The mass fraction of water is determined according to GOST 29208.2.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.08% with a confidence level of 0.95.

Permissible absolute total error of the analysis result is ±0.08% at a confidence level of 0.95.

6.6 Determination of the mass fraction of chlorides in terms of NaCl

The mass fraction of chlorides is determined according to GOST 29208.3.

When analyzing a liquid product, take a 10 ml sample prepared according to 6.2.

The mass fraction of chlorides in the liquid product in terms of sodium chloride (NaCl),%, is calculated by the formula

where

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.05% with a confidence level of 0.95.

Permissible absolute total error of the analysis result is ±0.05% at a confidence level of 0.95.

6.7 Determination of the mass fraction of sulfates

6.7.1 Apparatus

Laboratory scales of the 3rd accuracy class according to GOST 24104 with the maximum weighing limit of 500 g.

Photoelectrocolorimeter.

Volumetric flasks according to GOST 1770, version 1 or 2, with a capacity of 25 and 500 cm3.

Pipettes according to GOST 29228 with a capacity of 1 and 5 cm.

Pipettes according to GOST 29169 with a capacity of 5 and 10 cm.

Cup for weighing according to GOST 25336 SV 34/12 or SN 34/12, or SN 45/13.

6.7.2 Reagents

Distilled water according to GOST 6709.

Barium chloride, a solution with a mass fraction of 20%, is prepared according to GOST 4517.

Hydrochloric acid according to GOST 3118, solution with a mass fraction of 10%.

Soluble starch, a solution with a mass fraction of 1%, is prepared according to GOST 4517.

A solution containing sulfates is prepared according to GOST 4212.

An appropriate dilution is used to prepare a solution with a mass concentration of sulfates of 0.01 mg/cm. The diluted solution is used freshly prepared.

6.7.3 Building a calibration curve

The calibration graph is built according to GOST 10671.5, using volumetric flasks with a capacity of 25 cm3.

6.7.4 Conducting analysis

Weigh 14.5-15.5 g of the solid or 3 ml of liquid prepared in accordance with 6.2, recording the weighing result in grams to two decimal places. A weighed portion of the product is quantitatively transferred into a 500 ml volumetric flask, dissolved in water, the volume of the solution in the flask is adjusted to the mark with water and mixed thoroughly.

10 ml of the obtained solution (for a solid product) or 5 ml of the obtained solution (for a liquid product) are pipetted into a 25 ml volumetric flask, 1 ml of hydrochloric acid solution, 3 ml of starch solution, 3 ml of barium chloride solution are added, mix thoroughly. Then periodically stir every 10 minutes. Further, the analysis is carried out according to GOST 10671.

6.7.5 Handling results

The mass fraction of sulfates,%, is calculated from the formulas for a solid product

for liquid product

where is the mass of sulfates found from the calibration curve, mg;

- weight of the sample of the product, g;

- mass fraction of sodium chlorate in the liquid product, determined by 6.4, %.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.003% (for a solid product) and 0.05% (for a liquid product) with a confidence level of 0.95.

Permissible absolute total error of the analysis result is ±0.003% (for a solid product) and ±0.05% (for a liquid product) with a confidence level of 0.95.

6.8 Determination of the mass fraction of chromates

6.8.1 Apparatus

Laboratory scales of the 2nd and 3rd accuracy class according to GOST 24104 with the maximum weighing limit of 200 and 500 g, respectively.

Photoelectrocolorimeter.

Volumetric flasks according to GOST 1770 version 1 or 2 with a capacity of 25 cm3, 100 cm3 and 1 dm.

Pipettes according to GOST 29228 with a capacity of 1, 5, 10 cm.

Pipette according to GOST 29169 with a capacity of 10 cm.

Cup for weighing according to GOST 25336 SV 34/12 or SN 34/12, or SN 45/13.

6.8.2 Reagents

Acetone according to GOST 2603.

Distilled water according to GOST 6709.

Diphenylcarbazide, a solution of a mass concentration of 2.5 g / dm in acetone, is prepared as follows: (0.2500 ± 0.0002) g of diphenylcarbazide is dissolved in 100 ml of acetone. The solution is stored in a dark glass bottle.

Potassium dichromate according to GOST 4220.

Sulfuric acid according to GOST 4204, solution of molar concentration (HSO)=5 mol/dm.

A solution containing chromium (VI) is prepared according to GOST 4212. An appropriate dilution is used to prepare a solution containing 0.001 mg of chromium (VI) in 1 cm3. The diluted solution is used freshly prepared

6.8.3 Building a calibration curve

Reference solutions are prepared as follows.

In five volumetric flasks with a capacity of 25 cm add 2.0; 4.0; 6.0; 8.0; 10.0 ml of a dilute solution of potassium dichromate, which corresponds to 0.002; 0.004; 0.006; 0.008 and 0.010 mg of chromium (VI).

Add 1 ml of sulfuric acid solution, 1 ml of diphenylcarbazide solution to each flask, dilute the volumes of solutions with water to the mark and mix.

Simultaneously prepare a chromium-free control solution.

After 2 minutes, the optical densities of the reference solutions are measured with respect to the control solution on a photoelectric colorimeter at a wavelength of 540 nm, using a cuvette with a light-absorbing layer thickness of 20 mm.

Based on the data obtained, a calibration graph is built, plotting the entered mass of chromium in milligrams along the abscissa axis, and the corresponding value of optical density along the ordinate axis.

6.8.4 Conducting analysis

6.0-7.0 g of the solid product or 3 cm of the liquid product of brand A or 1 cm of the liquid product of brand B are weighed, recording the weighing result with two decimal places. Liquid product samples shall be prepared in accordance with 6.2.

The sample is quantitatively transferred into a volumetric flask with a capacity of 1 dm (for a solid and liquid product of brand B) and a capacity of 100 cm3 (for a liquid product of brand A). Dilute the volume of the solution in the flask with water to the mark and mix.

10 cm3 of the resulting solution is transferred with a pipette into a volumetric flask with a capacity of 25 cm3, and then the analysis is carried out in the same way as when constructing a calibration graph.

6.8.5 Handling results

Mass fraction of chromates, %, is calculated by the formulas

for solid product

for liquid product grade A

for liquid product grade B

where is the mass of chromium found from the calibration curve, mg;

- weight of the sample of the product, g;

2.23 - conversion factor Cr to CrO;

- mass fraction of sodium chlorate in the liquid product, determined by 6.4, %.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.002% for a solid product, 0.0003% for a liquid product of brand A and 0.01% for a liquid product of brand B at a confidence level of 0 .95.

The permissible absolute total error of the result of the analysis is ±0.002% for a solid product, ±0.0003% for a liquid product of brand A and ±0.03% for a liquid product of brand B with a confidence level of 0.95.

6.9 Determination of the mass fraction of water-insoluble substances

The mass fraction of substances insoluble in water is determined according to GOST 29208.1. When analyzing a liquid product, take a 40 ml sample prepared according to 6.2.

The mass fraction of water-insoluble substances in a liquid product,%, is calculated by the formula

where is the mass of the filter crucible together with the residue, g;

- weight of the filtering crucible, g;

- mass of sample for analysis, g;

- mass fraction of sodium chlorate in the liquid product, determined by 6.4, %.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the permissible discrepancy, equal to 0.003% for a solid product and 0.01% for a liquid product.

Permissible absolute total error of the analysis result is ±0.003% for a solid product and ±0.01% for a liquid product.

6.10 Determination of the mass fraction of iron Watch glass.
A portion of the product is quantitatively transferred to a porcelain cup, 20 cm3 of water and 20 cm3 of hydrochloric acid solution are added.

The cup is covered with a watch glass and heated in a water bath until the release of gas bubbles stops. Then the glass is removed, washed over the cup with water, after which the solution in the cup is evaporated to dryness in a water bath.

The residue in the cup is dissolved in 20 ml of water, the solution is transferred to a volumetric flask with a capacity of 100 ml, the volume of the solution in the flask is adjusted to the mark with water and mixed.

20 cm3 of the resulting solution is transferred with a pipette into a volumetric flask with a capacity of 50 cm3, and then the analysis is carried out according to GOST 10555 by the sulfosalicylic method, without adding a solution of hydrochloric acid to the analyzed solution

6.10.3 The mass fraction of iron, %, is calculated from the formulas for a solid product

for liquid product

where is the mass of iron found from the calibration curve, mg;

- weight of the sample of the product, g;

- mass fraction of sodium chlorate in the liquid product, determined by 6.4, %.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute discrepancy between which does not exceed the allowable discrepancy equal to 0.0015% with a confidence level of 0.95.

The permissible absolute total error of the analysis result is ±0.0015% for a solid product and ±0.002% for a liquid product with a confidence level of 0.95.

7 TRANSPORT AND STORAGE

7.1 Solid sodium chlorate is transported by rail and road in accordance with the rules for the carriage of goods in force for this type of transport, and the instructions for ensuring the safety of transportation of dangerous goods by road, approved in the prescribed manner. The product is transported in covered vehicles. By rail - wagon shipments.

7.2 Liquid sodium chlorate is transported by rail in special tanks of the consignor (consignee) with a safety cap.

7.2.1 The degree (level) of filling of tanks is calculated taking into account the full use of their capacity (carrying capacity) and the volumetric expansion of the product with a possible temperature difference along the route.

7.2.2 It is not allowed to get the product on the outer surface of the tank. If a liquid product comes into contact with the surface of the tank, it must be washed off with plenty of water.

7.2.3 Filling hatches of tanks are sealed with rubber gaskets.

7.3 Solid sodium chlorate must be transported in overpacks formed in accordance with GOST 26663, in drums - on flat pallets in accordance with GOST 9557, in textile bags - on flat pallets made of aluminum or light alloys, made in accordance with the requirements of GOST 9078 and regulatory and technical documentation, approved in accordance with the established procedure, in plastic bags - in box aluminum or light alloy pallets of a folding design, manufactured in accordance with the requirements of GOST 9570 and regulatory and technical documentation approved in the prescribed manner.

Means of fastening tare cargoes in a package - in accordance with GOST 21650.

The gross weight of the package must not exceed 1 ton.

Package dimensions - according to GOST 24597.

It is allowed, upon agreement with the consumer, to transport packaged solid sodium chlorate by road in unpackaged form.

7.4 Sodium chlorate in the manufacturer's packaging is stored in closed special rooms designed for the storage of explosive goods weighing no more than 200 tons.

Do not store sodium chlorate together with combustible substances, ammonia salts and acids.

Liquid sodium chlorate is stored in special containers equipped with air bubblers for mixing and heat exchangers for heating.

8 MANUFACTURER WARRANTY

8.1 The manufacturer guarantees that the quality of sodium chlorate meets the requirements of this standard, subject to the conditions of transportation and storage.

8.2 Warranty period of storage of solid sodium chlorate - 6 months, liquid - 1 year from the date of manufacture.



Electronic text of the document
prepared by CJSC "Kodeks" and checked against:
official publication
M.: Publishing house of standards, 1995

Sodium, calcium and magnesium chlorates are still used as non-selective herbicides - for cleaning railway tracks, industrial sites, etc.; as defoliants in cotton harvesting. Acid decomposition of chlorates is used in the production of chlorine dioxide "in place" (on-site) for bleaching high-strength pulp.

K2 Unfortunately, a serious disadvantage of this method is the low quality of household disinfectants and bleaches. After softening the "mandatory standardization" policy, manufacturers of "whiteness" products began to use their own specifications, lowering the hypochlorite content in the product from the standard 5% wt. up to 3% or less. Now, to get the same amount of chlorate in a good yield would require not only using up a lot more "whiteness" but also removing most of the water from the solution. Perhaps the most convenient may be to pre-concentrate the "whiteness" by partial freezing.

Professional liquid neutralizers for marine effluents contain up to 40% sodium hypochlorite.

K3 The disproportionation of hypochlorite to chloride and chlorate proceeds at a high rate at pH
K4 Indeed, a high-efficiency power supply of significant power for electrolysis is half the success of the case and a topic for special discussion.

Here I would like to remind you of the need to follow the rules of electrical safety.

Works involving electrolysis on a significant scale are considered to be particularly dangerous with regard to electric shock. This is due to the fact that contact of the experimenter's skin with the conductive electrolyte is almost inevitable. Gassing at the electrodes causes the formation of corrosive electrolyte aerosols that can deposit on electrical equipment components, especially when forced air cooling is used. The consequences can be very sad - from corrosion of metal parts and failure of the power supply to insulation breakdown with mains voltage on the cell and all the consequences for the experimenter.

Under no circumstances should high-voltage parts of the plant be installed in the immediate vicinity of the electrolytic cell. All components of the power source should be located at a sufficient distance from the cell and in such a way as to completely exclude both the ingress of electrolyte on them in the event of an accident of the cell, and the deposition of conductive aerosols. In this case, high-current wires from the source to the electrolyzer must have a sufficient cross section corresponding to the process current. All conductors (and their connections) directly connected to the mains must be hermetically sealed with moisture-resistant insulation.

Mandatory galvanic isolation of the cell from the mains. A conventional transformer provides adequate insulation, but it is strictly forbidden to power the electrolyser directly from autotransformers such as LATR, etc., since in this case the electrolyzer may be directly connected to the phase wire of the network. However, LATR (or household autotransformer) can be used to regulate the voltage on the primary winding of the main transformer. You just need to make sure that the power of the LATR is not less than the power of the main transformer.

For long-term operation of the installation, protection of electronic components from overheating and short circuits would be useful. To begin with, it is quite possible to limit yourself to installing a fuse in the primary winding of the transformer for a current corresponding to its rated power. It is also reasonable to supply power to the cell through an appropriate fuse (better - an adjustable electromagnetic release), bearing in mind that a short circuit in the cell is quite possible.

The question of the need to ground the installation in this case is not so simple. The fact is that in many residential premises, grounding is initially absent and it is not easy to arrange it on your own. In some cases, instead of grounding, cunning electricians organize "zeroing", connecting the ground bus and the network neutral directly at the consumer. In this case, the "grounded" device is directly connected to the current-carrying circuit of the network. Under our conditions, it can be recommended to give priority to the high-quality isolation of the electrolyzer from the network and the experimenter from the entire installation.

Safety rules should not be neglected for the reason that a long experiment in an amateur laboratory always attracts the attention of other people whose skills and behavior the experimenter cannot control. Be aware of those around you and work safely.