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| Sodium chlorate | |
| Sodium-chlorate-component-ions-2D.png | |
| Are common | |
|---|---|
| Systematic Name |
Sodium chlorate |
| Traditional names | Sodium hypochlorite |
| Chem. formula | NaClO3 |
| Physical properties | |
| State | colorless crystals |
| Molar mass | 106.44 g/mol |
| Density | 2.490; 2.493 g/cm³ |
| Thermal properties | |
| T. float. | 255; 261; 263 °C |
| T. kip. | decomposition 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 are based on standard conditions (25 °C, 100 kPa) unless otherwise stated. | |
Sodium chlorate- an inorganic compound, a salt of sodium metal and perchloric acid with the formula NaClO 3, colorless crystals, highly soluble in water.
Receipt
- Sodium chlorate is prepared by the action of perchloric acid on sodium carbonate:
- or by passing chlorine through a concentrated sodium hydroxide solution while heating:
- Electrolysis of aqueous solutions of sodium chloride:
Physical properties
Sodium chlorate - colorless crystals of cubic system, space group P 2 1 3 , cell parameters a= 0.6568 nm, Z = 4.
At 230-255°C it goes into another phase, at 255-260°C it goes into the monoclinic phase.
Chemical properties
- Disproportions when heated:
- Sodium chlorate is a strong oxidizing agent; in the solid state, when mixed with carbon, sulfur and other reducing agents, it detonates when heated or impacted.
Application
- Sodium chlorate has found use in pyrotechnics.
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Literature
- Chemical Encyclopedia / Editorial Board: Knunyants I.L. and others. - M.: Soviet Encyclopedia, 1992. - T. 3. - 639 p. - ISBN 5-82270-039-8.
- Chemist's Handbook / Editorial Board: Nikolsky B.P. and others. - 2nd ed., rev. - M.-L.: Chemistry, 1966. - T. 1. - 1072 p.
- Chemist's Handbook / Editorial Board: Nikolsky B.P. and others. - 3rd ed., rev. - L.: Chemistry, 1971. - T. 2. - 1168 p.
- Ripan R., Ceteanu I. Inorganic chemistry. Chemistry of metals. - M.: Mir, 1971. - T. 1. - 561 p.
| This is a draft article about inorganic matter. You can help the project by adding to it. |
Excerpt characterizing Sodium Chlorate
It was about 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 up before him like an amphitheater across the rising terrain.Up and to the left along this amphitheater, cutting it, wound the great Smolensk road, passing through a village with a white church, which lay five hundred steps in front of the mound and below it (this was Borodino). The road crossed under the village across a bridge and, through ups and downs, wound higher and higher to the village of Valuev, visible six miles away (Napoleon was now standing there). Beyond Valuev, the road disappeared into a yellowing forest on the horizon. In this birch and spruce forest, to the right of the direction of the road, the distant cross and bell tower of the Kolotsk Monastery glittered in the sun. All along 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’s troops. To the right, along the flow of the Kolocha and Moskva rivers, the area was gorged and mountainous. Between their gorges the villages of Bezzubovo and Zakharyino could be seen in the distance. To the left, the terrain was more level, there were fields with grain, and one smoking, burnt village could be seen - Semenovskaya.
Everything that Pierre saw to the right and to the left was so vague that neither left nor Right side the field did not completely satisfy his idea. Everywhere there was not the battle that he expected to see, but fields, clearings, troops, forests, smoke from fires, villages, mounds, streams; and no matter how much Pierre tried, he could not find a position in this lively area and could not even distinguish your troops from the enemy.
“We need to ask someone who knows,” he thought and turned to the officer, who was looking with curiosity at his huge non-military figure.
“Let me ask,” Pierre turned to the officer, “what village is ahead?”
- Burdino or what? - said the officer, turning to his comrade with a question.
“Borodino,” the other answered, correcting him.
The officer, apparently pleased with the opportunity to talk, moved towards Pierre.
- Are ours there? – asked Pierre.
“Yes, and the French are further away,” said the officer. - There they are, visible.
- Where? Where? – asked Pierre.
- You can see it with the naked eye. Yes, here you go! “The officer pointed to the smoke visible to the left across the river, and his face showed that stern and serious expression that Pierre had seen on many faces he met.
- Oh, these are the French! And there?.. - Pierre pointed to the left at the mound, near which troops could be seen.
- These are ours.
- Oh, ours! And there?.. - Pierre pointed to another distant mound with a large tree, near a village visible in the gorge, where fires were also smoking and something was black.
“It’s him again,” said the officer. (This was the Shevardinsky redoubt.) - Yesterday it 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.” 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 Kolocha. Here, you see, where the rows of mown hay still lie in the low place, here is the bridge. This is our center. Our right flank is here (he pointed sharply to the right, far into the gorge), there is the Moscow River, and there we built three very strong redoubts. Left flank... - and then the officer stopped. - You see, it’s difficult to explain to you... Yesterday our left flank was right there, in Shevardin, you see, where the oak is; and now we have carried the left wing back, now there, there - see the village and the smoke? “This is Semenovskoye, right here,” he pointed to the Raevsky mound. “But it’s unlikely there will be a battle here.” That he transferred troops here is a deception; he will probably go around to the right of Moscow. Well, no matter where it is, many will be missing tomorrow! - said the officer.
The old non-commissioned officer, who approached the officer during his story, silently awaited the end of his superior’s speech; but at this point he, obviously dissatisfied with the officer’s words, interrupted him.
“You have to go for the tours,” he said sternly.
The officer seemed embarrassed, as if he realized that he could think about how many people would be missing tomorrow, but he shouldn’t talk about it.
“Well, yes, send the third company again,” the officer said hastily.
- Who are you, not a doctor?
GOST 12257-93
Group L17
INTERSTATE STANDARD
SODIUM CHLORATE TECHNICAL
Specifications
Sodium chlorate for industrial use. Specifications
OKP 21 4722
Date of introduction 1996-01-01
Preface
1 DEVELOPED BY MTK 89
INTRODUCED by Gosstandart of Russia
2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Protocol N 3-93 of 02/17/93)
The following voted for adoption:
State name | Name of the national standardization body |
Republic of Azerbaijan | Azgosstandart |
Republic of Armenia | Armgosstandard |
Republic of Belarus | Belstandart |
The Republic of Moldova | Moldovastandard |
Russian Federation | Gosstandart of Russia |
Turkmenistan | Turkmengosstandard |
The Republic of Uzbekistan | Uzgosstandart |
Ukraine | State Standard of Ukraine |
3 Committee Resolution Russian Federation on standardization, metrology and certification dated December 23, 1994 N 349, the interstate standard GOST 12257-93 “Technical sodium chlorate. Technical conditions” was put into effect directly as a state standard of the Russian Federation on January 1, 1996.
4 INSTEAD 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, highly effective oxidizing agents 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 requirements security
GOST 1770-74 Laboratory glassware. Cylinders, beakers, flasks, test tubes. Specifications
GOST 2517-85 Oil and petroleum products. Sampling methods
GOST 2603-79 Reagents. Acetone. Specifications
GOST 3118-77 Reagents. Hydrochloric acid. Specifications
GOST 4148-78 Reagents. Iron (II) sulfate 7-hydrate. 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 preparing auxiliary reagents and solutions used in 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 technical conditions
GOST 9147-80 Porcelain laboratory utensils and equipment. Specifications
GOST 9557-87 Flat wooden pallet measuring 800x1200 mm. Specifications
GOST 9570-84 Box and rack pallets. General technical conditions
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 sulfate impurities
GOST 10931-74 Reagents. Sodium molybdate acid 2-water. Specifications
GOST 14192-77 * Marking of goods
________________
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 for fastening packaged cargo in transport packages. General requirements
GOST 24104-88 * Laboratory scales general purpose and exemplary. General technical conditions
________________
* GOST R 53228-2008 is in force on the territory of the Russian Federation, hereinafter in the text. - Database manufacturer's note.
GOST 24597-81 Packages of packaged cargo. Main parameters and dimensions
GOST 26663-85 Transport packages. Formation using packaging tools. General technical requirements
GOST 27025-86 Reagents. General test instructions
GOST 29169-91 Laboratory glassware. Single mark pipettes
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. Gravity 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 dichromate
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 manufactured in accordance with the requirements of this standard according to 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.
Sodium chlorate grade A 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
Indicator name | Standard for sodium chlorate |
||
solid | |||
grade A | brand B |
||
1 Mass fraction of sodium chlorate, %, not less | |||
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 chromate (CrO), %, no more | |||
6 Mass fraction of water-insoluble substances, %, no more | |||
7 Mass fraction of iron (Fe), %, no more | |||
Note - Norms of impurities in a liquid product are given in terms of 100% product |
|||
3.5 Marking
3.5.1 Special stencils must be applied to the tank in accordance with the rules for the transportation 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 danger sign corresponding to the classification code 5112 (class 5, subclass 5.1, drawing number 5), UN serial number 1495 for a solid product and 2428 for a liquid product.
3.5.4 Labeling characterizing 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 packaged in liner bags made of polyethylene film with a thickness of at least 0.100 mm, enclosed in: drums according to GOST 5044 made of galvanized steel, version B with a hatch diameter of 300 mm or version B, 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 made of chlorine fabric or fire-resistant textile bags.
Insert bags, bags made of chlorine fabric and fire-resistant textile bags are manufactured according to regulatory 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.
Plastic bags are sealed. Chlorine and fireproof bags are sewn up by machine without gripping the plastic bag.
Product weight in the bag - (50±1) kg.
Solid sodium chlorate is not allowed to get between plastic and fabric bags, as well as on the outer surface of the container.
4 SAFETY AND ENVIRONMENTAL PROTECTION 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 can cause an explosion. Mixtures of the product with flammable substances and mineral acids are explosive and may spontaneously ignite due to increased temperature, impact and friction.
4.4 Production premises must be equipped with supply and exhaust ventilation. Equipment, pipelines, fittings must be sealed. Sampling sites and dust-producing sites must be equipped with local suction. Relevant equipment and pipelines must be protected from static electricity and explosion-proof.
4.5 For personal protection of personnel, special clothing must be used in accordance with standard standards and individual respiratory and eye protection equipment: a gas mask of grade B or BKF, a respirator (when working with solid sodium chlorate), goggles.
4.6 If the product gets on your clothing, you must change it immediately. Sodium chlorate is washed off from the skin and mucous membranes with soap and water or baking soda. If sodium chlorate gets inside, induce vomiting, rinse the stomach and provide medical assistance. Special clothing should be washed 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 into a bucket made of vinyl plastic or titanium and wash the spill or spillage area with water. To remove the product, use a tool made of non-sparking material.
4.8 Cleaning the premises using wet or vacuum cleaning.
4.9 In case of fire, extinguish with water.
4.10 Solid waste must be burned in a special area outside the plant. Liquid waste is sent for neutralization Wastewater and into the sewer system of chemically contaminated wastewater. Gas emissions are diluted with inert gas, cleaned of chlorine and released into the atmosphere.
5 ACCEPTANCE
5.1 Sodium chlorate is taken in batches. A batch is considered to be a quantity of a product that is uniform in 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;
- number of containers in the batch;
- gross and net weight;
- classification code of the group according to GOST 19433;
- results of analyzes performed or confirmation of 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 compliance of the quality of the product with the requirements of this standard, the sample volume of the product is 10% of packaging units, but not less than three units or each tank.
5.4 If unsatisfactory analysis results are obtained for at least one of the indicators, a repeat analysis is carried out on a double sample or a newly selected sample from the tank.
The results of the re-analysis apply to the entire batch.
6 METHODS OF ANALYSIS
6.1 Sampling
6.1.1 Point 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. Sampling with a scoop from the stream is allowed. The mass of a spot 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 stirred. The heating temperature should be from 60 to 80 °C. The volume of a spot sample must be at least 1 dm.
6.1.3 Spot samples are combined together, mixed and an average sample of a solid product weighing at least 250 g and a liquid product with a volume of at least 0.5 dm3 is taken. 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 the solid product in a plastic film bag, which is sealed.
A label indicating the name of the product (its brand), batch number (tank), date of sampling and the name of the person who took the sample is affixed to the jar or bag.
6.2 Liquid sample preparation
Before analysis, a sample of the 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 mass of the liquid product sample.
6.3 General instructions for conducting analysis - according to GOST 27025.
It is allowed to use other measuring instruments with metrological characteristics and equipment with technical characteristics no worse, as well as reagents of no lower quality than those indicated.
Rounding of analysis results to the decimal place specified in the technical requirements table.
6.4 Determination of mass fraction of sodium chlorate
6.4.1 Hardware
Laboratory scales of the 2nd accuracy class according to GOST 24104 with the largest weighing limit of 200 g.
Burette according to GOST 29252 with a capacity of 50 cm.
Measuring flask according to GOST 1770 version 1 or 2 with a capacity of 500 cm.
Conical flask type Kn according to GOST 25336, version 1 or 2, capacity 250 cm.
Pipette according to GOST 29228 with a capacity of 10 cm.
Pipette according to GOST 29169 with a capacity of 10 and 25 cm.
Weighing cup according to GOST 25336
6.4.2 Reagents
Distilled water according to GOST 6709.
Iron (II) sulfate, 7-water according to GOST 4148, solution of molar concentration (FeSO 7HO) = 0.1 mol/dm, is prepared as follows: 28 g of iron sulfate is dissolved in 500 cm of water, to which 100 cm of concentrated water is carefully added sulfuric acid. Then dilute with water to 1 dm and, if necessary, filter.
Potassium permanganate according to GOST 20490, solution of molar concentration (KMnO) = 0.1 mol/dm, prepared according to GOST 25794.2.
Phosphoric acid according to GOST 6552.
Sulfuric acid according to GOST 4204.
Sodium molybdate acid according to GOST 10931, solution with mass fraction
6.4.3 Conducting analysis
1.3-1.7 g of solid or 2.5 cm of liquid product prepared according to paragraph 4.2 is weighed, recording the weighing result in grams with four decimal places. A sample of the product is transferred quantitatively 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 cm of the resulting solution is pipetted into a conical flask, then pipetted with 25 cm of ferrous sulfate solution, 6 cm of sulfuric acid, 5 cm of orthophosphoric acid, 3-5 drops of sodium molybdate solution, mix the contents of the flask and titrate with a solution of potassium permanganate until a slightly 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 Processing results
The mass fraction of sodium chlorate,%, is calculated using the formula
where is the volume of a solution of potassium permanganate with a molar concentration of exactly 0.1 mol/dm3, consumed for titration in the control experiment, cm;
- the volume of a solution of potassium permanganate with a molar concentration of exactly 0.1 mol/dm3, consumed for titrating the sample, cm;
0.001774 - mass of sodium chlorate corresponding to 1 cm of potassium permanganate solution with a molar concentration of exactly 0.1 mol/dm, g;
- mass of a 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 permissible discrepancy equal to 0.3% with a confidence probability of 0.95.
The 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 according to GOST 29208.4. When analyzing a liquid product, take 5 cm of a sample prepared by
6.5 Determination of 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 permissible discrepancy equal to 0.08% with a confidence probability of 0.95.
The permissible absolute total error of the analysis result is ±0.08% with a confidence probability 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 10 cm of a sample prepared according to 6.2.
The mass fraction of chlorides in a liquid product in terms of sodium chloride (NaCl), %, is calculated using 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 permissible discrepancy equal to 0.05% with a confidence probability of 0.95.
The permissible absolute total error of the analysis result is ±0.05% with a confidence probability of 0.95.
6.7 Determination of mass fraction of sulfates
6.7.1 Hardware
Laboratory scales of the 3rd accuracy class according to GOST 24104 with the largest weighing limit of 500 g.
Photoelectric colorimeter.
Measuring flasks according to GOST 1770, version 1 or 2, with a capacity of 25 and 500 cm.
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.
Weighing cup 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, solution with a mass fraction of 1%, is prepared according to GOST 4517.
A solution containing sulfates is prepared according to GOST 4212.
A solution is prepared by appropriate dilution mass concentration sulfates 0.01 mg/cm. The diluted solution is used freshly prepared.
6.7.3 Construction of a calibration graph
The calibration curve is constructed according to GOST 10671.5, using volumetric flasks with a capacity of 25 cm.
6.7.4 Conducting analysis
14.5-15.5 g of solid or 3 cm of liquid prepared according to 6.2 are weighed, recording the result in grams to two decimal places. A sample of the product is transferred quantitatively into a 500 cm3 volumetric flask, dissolved in water, the volume of the solution in the flask is adjusted to the mark with water and mixed thoroughly.
10 cm of the resulting solution (for a solid product) or 5 cm of the resulting solution (for a liquid product) is pipetted into a 25 cm volumetric flask, add 1 cm of hydrochloric acid solution, 3 cm of starch solution, 3 cm of barium chloride solution, mix thoroughly. Then stir periodically every 10 minutes. Next, the analysis is carried out according to GOST 10671.
6.7.5 Processing results
The mass fraction of sulfates, %, is calculated using the formulas for the solid product
for liquid product
where is the mass of sulfates found from the calibration curve, mg;
- mass of the product sample, g;
- mass fraction sodium chlorate in the liquid product, determined at 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 0.05% (for a liquid product) with a confidence level of 0.95.
The 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 Hardware
Laboratory scales of the 2nd and 3rd accuracy classes according to GOST 24104 with the largest weighing limit of 200 and 500 g, respectively.
Photoelectric colorimeter.
Measuring flasks according to GOST 1770, version 1 or 2, with a capacity of 25 cm, 100 cm 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.
Weighing cup 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 with 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 cm of acetone. The solution is stored in a dark glass bottle.
Potassium dichromate according to GOST 4220.
Sulfuric acid according to GOST 4204, solution molar concentration (HSO) = 5 mol/dm.
A solution containing chromium (VI) is prepared according to GOST 4212. By appropriate dilution, prepare a solution containing 0.001 mg of chromium (VI) per 1 cm. The diluted solution is used freshly prepared
6.8.3 Construction of a calibration graph
Reference solutions are prepared as follows.
Add 2.0 to five volumetric flasks with a capacity of 25 cm; 4.0; 6.0; 8.0; 10.0 cm of a diluted solution of potassium dichromate, which corresponds to 0.002; 0.004; 0.006; 0.008 and 0.010 mg chromium (VI).
Add 1 cm of sulfuric acid solution and 1 cm of diphenylcarbazide solution to each flask, adjust the solution volumes to the mark with water and mix.
At the same time, prepare a control solution that does not contain chromium.
After 2 minutes, measure the optical densities of the reference solutions relative to the control solution on a photoelectrocolorimeter 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 constructed, plotting the introduced mass of chromium in milligrams on the abscissa axis, and the corresponding optical density value on the ordinate axis.
6.8.4 Conducting analysis
6.0-7.0 g of solid product or 3 cm of liquid product of grade A, or 1 cm of liquid product of grade B is weighed, recording the weighing result to two decimal places. Samples of the liquid product must be prepared in accordance with 6.2.
The sample is quantitatively transferred into a volumetric flask with a capacity of 1 dm3 (for solid and liquid product grade B) and a capacity of 100 cm3 (for liquid product grade A). Fill the volume of the solution in the flask with water to the mark and mix.
10 cm of the resulting solution is pipetted into a 25 cm volumetric flask and then the analysis is carried out in the same way as when constructing a calibration graph.
6.8.5 Processing results
The mass fraction of chromates,%, is calculated using 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;
- mass of the product sample, g;
2.23 - conversion factor of Cr to CrO;
- mass fraction of sodium chlorate in the liquid product, determined at 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 0.002% for a solid product, 0.0003% for a liquid product of grade A and 0.01% for a liquid product of grade B with a confidence probability of 0 .95.
The permissible absolute total error of the analysis result is ±0.002% for a solid product, ±0.0003% for a liquid product of grade A and ±0.03% for a liquid product of grade B with a confidence level of 0.95.
6.9 Determination of the mass fraction of water-insoluble substances
The mass fraction of water-insoluble substances is determined according to GOST 29208.1. When analyzing a liquid product, take 40 cm of a sample prepared according to 6.2.
The mass fraction of water-insoluble substances in a liquid product, %, is calculated using the formula
where is the mass of the filter crucible together with the residue, g;
- mass of the filter crucible, g;
- mass of sample for analysis, g;
- mass fraction of sodium chlorate in the liquid product, determined at 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.
The 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 sample of the product is transferred quantitatively into a porcelain cup, 20 cm of water and 20 cm of hydrochloric acid solution are added.
The cup is covered with a watch glass and heated in a water bath until the emission of gas bubbles stops. Then the glass is removed, washed over a 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 cm of water, the solution is transferred to a 100 cm volumetric flask, the volume of the solution in the flask is adjusted to the mark with water and mixed.
20 cm of the resulting solution is pipetted into a 50 cm volumetric flask and then the analysis is carried out according to GOST 10555 using the sulfosalicylic method, without adding hydrochloric acid solution to the analyzed solution
6.10.3 Mass fraction of iron,%, is calculated using formulas for a solid product
for liquid product
where is the mass of iron found from the calibration curve, mg;
- mass of the product sample, g;
- mass fraction of sodium chlorate in the liquid product, determined at 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 0.0015% with a confidence probability 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 TRANSPORTATION AND STORAGE
7.1 Solid sodium chlorate is transported by rail and road in accordance with the rules for the transportation of goods in force for this type of transport and 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 railway- 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 volumetric expansion of the product with a possible temperature difference along the route.
7.2.2 The product must not come into contact with the outer surface of the tank. If a liquid product gets on the surface of the tank, it must be washed off with copious amounts of water.
7.2.3 Tank filling hatches are sealed with rubber gaskets.
7.3 Solid sodium chlorate must be transported in transport packages 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, manufactured in accordance with the requirements of GOST 9078 and regulatory and technical documentation, approved in the prescribed manner, in plastic bags - in aluminum or light alloy box 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 for fastening containerized cargo in a package - in accordance with GOST 21650.
The gross weight of the package should not exceed 1 ton.
The dimensions of the package are according to GOST 24597.
It is allowed, by 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 intended for storing explosive goods weighing no more than 200 tons.
Sodium chlorate must not be stored together with flammable 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 The guaranteed shelf life of solid sodium chlorate is 6 months, liquid - 1 year from the date of manufacture.
Electronic document text
prepared by Kodeks JSC and verified against:
official publication
M.: Standards Publishing House, 1995
Also registered in: USA
Basic information:
| Broad spectrum, systemic that moves to all parts of the weed. Phytoxic to all businesses. |
| White powder |
Release:
sodium chlorate: behavior in the environment
| Index | Meaning | Explanation | ||
| Solubility in water at 20 o C (mg/l) | 650000 A5 High||||
| Solubility in organic solvents at 20 o C (mg/l) | Insoluble A5 - Most organic Solvents -||||
| Melting point (o C) | 255 A5 -||||
| Boiling point (o C) | Decomposes to boiling point A4 -||||
| Decomposition temperature (o C) | 260 A3 -||||
| Flash point (o C) | Flammability is not high A5 -||||
| Partition coefficient in the octanol/water system at pH 7, 20 o C | P: 1.26 X 10 -03 Calculated -||||
| Specific Gravity (g/ml) / Specific Gravity | 2.499 L3 -||||
| Dissociation constant (pKa) at 25 o C | -2 A4 -||||
| Note: Very Strong Acid | ||||
| Vapor pressure at 25 o C (MPa) | 5.2 X 10 -06 A2 Intermediate state||||
| Henry's law constant at 25 o C (Pa*m 3 /mol) | 5.2 X 10 -09 A3 - Not volatile||||
| Henry's law constant at 20 o C (dimensionless) | 3.50 X 10 -16 Calculated Not volatile||||
| Decay period in soil (days) | DT50 (typical) 200 F3 Stable||||
| According to laboratory studies of the European Union, DT50 is 46.7-314.6 days | ||||
| Aqueous photolysis DT50 (days) at pH 7 | Value: Stable A5 Stable||||
| - | ||||
| Aqueous hydrolysis DT50 (days) at 20 o C and pH 7 | Value: Stable A5 Very stable||||
| Not sensitive to pH | ||||
| Water deposition DT50 (days) | - - -||||
| Only aqueous phase DT50 (days) | - - -||||
| Potential leaching index GUS | 6.90 Calculated High leachability||||
| Concentration growth index in groundwater SCI (µg/l) at an application dose of 1 kg/ha (l/ha) | Value: 4.51 X 10 +01 Calculated -||||
| - | ||||
| Potential for particle bound transport index | - Average is calculated||||
| Koc - organic carbon distribution coefficient (ml/g) | 10 F3 Very mobile||||
| pH stability: | ||||
| Note: | ||||
| Freundlich adsorption isotherm | Kf: -- | -|||
| - | ||||
| Maximum UV absorption (l/(mol*cm)) | - - -||||
sodium chlorate: ecotoxicity
| Index | Meaning | Source / Qualitative indicators / Other information | Explanation | |
| Bioconcentration factor | BCF: -- | -|||
| Bioaccumulation potential | - Calculated Low||||
| LD50 (mg/kg) | > 5000 A5 Rat Low||||
| Mammals - Short-term food NOEL | (mg/kg): -- | -|||
| Birds - Acute LD50 (mg/kg) | 2510 A5 Mallard Duck Low||||
| Birds - Acute toxicity (CK50/LD50) | - - -||||
| Fish - Acute 96 hour CK50 (mg/l) | 10000 G2 Unknown species Low||||
| Fish - Chronic 21 day NOEC (mg/l) | 500 A5 Danio rerio -||||
| Aquatic invertebrates - Acute 48 hour EC50 (mg/l) | 919.3 A5 Short||||
| Aquatic Invertebrates - Chronic 21 day NOEC (mg/l) | 500 A5 Daphnia magna (Daphnia major, Large water flea) -||||
| Aquatic crustaceans - Acute 96 hour CK50 (mg/l) | - - -||||
| Bottom microorganisms - Acute 96 hour CK50 (mg/l) | - - -||||
| NOEC , static, Water (mg/l) | - - -||||
| Benthic microorganisms - Chronic 28 day NOEC, Sediment (mg/kg) | - - -||||
| aquatic plants- Acute 7 day EC50, biomass (mg/l) | 134 A5 Lesser duckweed Short||||
| Algae - Acute 72 hour EC50, growth (mg/l) | 1595 A5 Green algae (Scenedesmus subspicatus) Short||||
| Algae - Chronic 96 hour NOEC, growth (mg/l) | - - -||||
| Bees - Acute 48 hour LD50 (µg/individual) | > 75 A5 Oral Moderate||||
| Soil worms - Acute 14-day CK50 (mg/kg) | > 750 A5 Moderate||||
| Soil worms - Chronic 14-day maximum non-active concentration of the substance, reproduction (mg/kg) | - - -||||
| Other Arthropods (1) | LR50 (g/ha): 84.4 A5 Predatory mite Moderately hazardous at 1 kg/ha||||
| Other Arthropods (2) | LR50 (g/ha): 250.6 A5 Rider Moderately hazardous at 1 kg/ha||||
| Soil microorganisms | Nitrogen mineralization: -47Action (%)||||
| Available data on the mesoworld (mesocosm) | NOEAEC mg/l: - - -||||
sodium chlorate: human health
Basic indicators:
| Index | Meaning | Source / Qualitative indicators / Other information | Explanation | |
| Mammals - Acute oral LD50 (mg/kg) | > 5000 A5 Rat Low||||
| Mammals - Dermal LD50 (mg/kg body weight) | > 2000 A5 Rat -||||
| Mammals - Inhalation CK50 (mg/l) | > 3.9 A5 Rat -||||
| ADI - permissible daily dose (mg/kg body weight per day) | Not defined A5 -||||
| ARfD - average daily intake (mg/kg body weight per day) | Not defined A5 -||||
| AOEL - permissible systemic operator exposure level | 0.35 A5 Rat, SF=200 -||||
| Skin absorption (%) | - - -||||
| Dangerous Substances Directive 76/464/EC | - - -||||
| Types of restrictions | - - -||||
| by category | Are common:||||
| , | ||||
| Examples of European | ||||
The invention relates to the production of sodium chlorate, widely used in various areas industry. Electrolysis of a sodium chloride solution is carried out first in chlorine diaphragm electrolyzers. The resulting chloride-alkaline solutions and electrolytic chlorine gas are mixed to produce 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 partially removed to produce hydrochloric acid from chlorine gas for acidification of chlorate electrolysis and the use of chloride alkaline solutions for irrigation of sanitary columns. The technical result is a reduction in energy consumption and the possibility of organizing autonomous production. 1 salary.
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 (Berthollet 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. There is a known method for producing sodium chlorate by a chemical method, in which solutions of sodium hydroxide are subjected to chlorination to produce sodium chlorate. According to its technical and economic indicators chemical method does not withstand competition with electrochemical, therefore at present it is practically not used (L.M. Yakimenko “Production of chlorine, caustic soda and inorganic chlorine products”, Moscow, from “Chemistry”, 1974, p. 366). There is a known method for producing sodium chlorate by electrolysis of a sodium chloride solution in a cascade of diaphragm-less electrolyzers to produce 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 inorganic compounds, Moscow, publishing house "Chemistry", 1984, pp. 35-70). This method is closest to the proposed invention. The main technological stage, diaphragm-less electrolysis of sodium chloride solutions, proceeds with a current efficiency of 85-87%. The process is carried out on ruthenium oxide anodes at a temperature of 70-80 o C, pH 7 with constant acidification of the electrolyte with a 10% solution of hydrochloric acid. Before entering the solid product separation stage, the electrolyte is alkalized to an excess of alkali of 1 g/l with the addition of a reducing agent to destroy the corrosive sodium hypochlorite, which is always present in electrolysis products. A side anodic process during the electrolysis of chloride solutions is the release of Cl 2 , which not only reduces the current output, but also requires 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: for 1 ton of sodium chlorate, ~120 kg of 31% hydrochloric acid and 44 kg of 100% NaOH are consumed. For the same reason, chlorate production is organized where there is chlorine electrolysis, supplying 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 disadvantages: high energy costs (not very high current output) and the impossibility of organizing autonomous production. The objective of the present 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 liquors with a composition of 120-140 g/l NaOH and 160-180 g/l NaCl, which are then fully or partially subjected to interaction between itself to obtain a chloride-chlorate solution of 50-60 g/l NaClO 3 and 250-270 g/l NaCl, sent for non-diaphragm electrolysis. The process of chlorate non-diaphragm electrolysis is carried out with 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 reaction products of alkali and chlorine from diaphragm electrolysis, is sent to non-diaphragm chlorate electrolysis. Before entering the solid product separation stage, the electrolyte is alkalized to an excess of alkali of 1 g/l with the addition of a reducing agent to destroy sodium hypochlorite. In the partial removal 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 when cleaning electrolysis gases. With this scheme, 30-35 g of sodium chloride out of 300-310 g contained in each liter of the original solution is processed under chlorine electrolysis conditions. This scheme causes a reduction in energy costs, because The current output of chlorine electrolysis is higher, and the voltage on the electrolyzers is lower than in chlorate electrolysis, and when partially electrochemical oxidation of sodium chloride into chlorate is carried out under the conditions of chlorine electrolysis, the performance of the entire process as a whole is improved. In addition, when using the described scheme, the cost of cooling the electrolysis is reduced, since chlorine electrolyzers do not require cooling. Note that a deeper activation of chloride under chlorine electrolysis conditions 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 feeding solutions with an increased NaClO 3 concentration to chlorate electrolysis, obtained from alkali solutions that are more concentrated in NaOH than diaphragm liquors, for the chlorination of which chlorine containing inerts can be utilized. The electrolyte of chlorine electrolysis can be mixed with chlorine gas not completely, but partially. In this case, part of the electrolytic lyes of diaphragm electrolysis, not intended for chlorination, is allocated for use in sanitary columns, and an equivalent part of the electrolytic chlorine can be used for the synthesis of hydrochloric acid. Directing electrolytes 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 electrolysers 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 diaphragm-less electrolysis, or whether the electrolytes of chlorine electrolyzers will be used only for alkalization, and electrolytic chlorine - for the synthesis of perchloric acid for acidification in the chlorate electrolysis scheme, or part of the products will be used in one direction, and part in the other. The advantages of the proposed method are:
1) reduction in energy costs due to the initial stage of electrolysis with a higher current output and at a lower voltage than in conventional chlorate electrolysis: current output is 92-94% and a voltage of 3.2 V in chlorine electrolysis versus 85-90% and 3 .4 V and higher, respectively, in chlorate;
2) the possibility of obtaining, simultaneously with the main product - sodium chlorate - alkaline solutions required according to the technological scheme for alkalization and irrigation of sanitary columns;
3) the possibility of using chlorine produced in chlorine electrolyzers to produce hydrochloric acid on site for acidification of chlorate electrolysis. Example
In an experimental electrolyzer, 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 contain 140 g/l NaOH and 175 g/l NaCl , mixed with anode chlorine gas and a chloride-chlorate solution of 270 g/l NaCl and 50 g/l NaClO 3 is obtained. This solution is further fed to diaphragmless chlorate electrolysis, carried out in a cascade of 4 electrolysers 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 NaClO3. Thus, from one 1 liter of initial chloride solution, taking into account a 10% reduction in the volume of the solution due to the entrainment of water vapor with electrolysis gases and 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 electrolyzer was 3.3 V with a current efficiency of 93%. The average voltage across the chlorate electrolyzer was 3.4 V with a current efficiency of 85%. Specific energy consumption W (kWh/t. Thus, the reduction in energy costs was 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 the electrolysis of the sodium chloride solution is first carried out in chlorine diaphragm electrolyzers to produce alkali-chloride solutions and electrolytic chlorine gas, which are mixed to produce a chloride-chlorate solution and sent, after mixing with the mother liquor of the crystallization stage, to diaphragm-free electrolysis. 2. The method according to claim 1, characterized in that the products of diaphragm electrolysis are partially withdrawn to produce hydrochloric acid from chlorine gas for acidification of chlorate electrolysis and the use of chloride-alkaline solutions for irrigation of sanitary columns.Chlorates are salts of one of the oxygen acids of chlorine, chloric acid - HCl3. When heated, perchloric acid and its salts easily decompose with the release of oxygen, turning into salts of perchloric acid - perchlorates. All chlorates are more or less soluble in water. The solubility of sodium chlorate in water is 50.2% at 20° and 69.7% at 100°. In aqueous solutions, chlorates are extremely stable even in the presence of many oxidizing substances.[...]
Sodium chlorate can change the organoleptic qualities of water, giving it a bitter-salty taste. To establish the threshold concentrations of the test salt in water based on taste, several series of experiments were carried out using standard methods with aqueous solutions of sodium chlorate at temperatures of 20 and 60°. The experimental results are presented in table. 1.[ ...]
Sodium chlorate is a white or yellowish crystalline powder that ho-. Absorbs water well and disintegrates when heated to 300°C.[...]
Sodium chlorate is low-toxic for warm-blooded animals, LD50 for rats is 1.2 g per 1 kg, however, cases of fatal poisoning of people when using sodium chlorate to control weeds have been reported abroad. Acts on the blood, causes the breakdown of red blood cells and converts hemoglobin into methemoglobin. Clinic of poisoning: jaundice, vomiting bile, gastrointestinal disorders, skin rashes, fever.[...]
Sodium chlorate - crystalline substance white, Ty 248° C, density 7.49 g/cm3, decomposition begins at 265° C, highly soluble in water, ammonia, alcohol, glycerin, acetone, poorly soluble in hexane and toluene. [...]
MPC of sodium chlorate in the air of the working area is 5 mg/m3.[...]
Our studies of sodium chlorate included acute and subacute toxicological experiments, as well as a chronic sanitary toxicological experiment.[...]
To study the effect of sodium chlorate on the course of mineralization of organic pollution, several series of experiments were carried out to determine the dynamics of BOD under the influence of sodium chlorate concentrations of 20 and 100 mg/l. Experiments were carried out with both 5-day and 20-day duck incubations. The experimental results are presented in table. 2.[...]
In animals receiving sodium chlorate at a dose of 500 mg/kg, no changes were found in the morphological composition of the blood (number of erythrocytes, leukocytes, reticulocytes) that could be associated with the effects of sodium chlorate, and no changes were noted in the hemoglobin content , in the ratio of protein fractions of blood serum. The weight gain of the animals was the same as the weight gain of the control group.[...]
There is also a combination preparation containing sodium chlorate, borax and TCA.[...]
Acute experiments to study the effect of sodium chlorate on the body of warm-blooded animals with a single oral administration were carried out on white mice, white rats and guinea pigs. The experiments used 50 mice, 24 rats and 30 guinea pigs. The substance was administered to animals in an aqueous solution on an empty stomach. The clinical picture of poisoning was characterized by severe shortness of breath, cyanosis of the tip of the nose and paws, and tonic convulsions during the period of agony. These phenomena were especially pronounced in white mice, less pronounced in rats and very little in guinea pigs. Animals receiving lower doses died due to the same phenomena, but at a later date. Data from acute experiments were subjected to statistical processing using the Miller and Tainterag method. The lowest value of the mean lethal dose ■ was observed in white mice (3600±705 mg/kg). In white rats and guinea pigs it was approximately at the same level (6500±±417 mg/kg and 6100±383 mg/kg, respectively).[...]
The product must consist primarily of sodium chlorate and be in the form of white or slightly colored crystals, free from foreign impurities or added modifying agents.[...]
The results of acute experiments allow us to classify sodium chlorate as a moderately toxic substance and confirm the literature data that chlorate poisoning causes methemoglobinemia. It turned out that the most high level methemoglobinemia reaches 4-6 hours after poisoning.[...]
Defoliants containing sodium chlorate are common in the United States. To reduce the flammability of sodium chlorate, sodium polyborates or sodium metaborates are added to preparations. The most widely used is sodium chlorate pentaborate, containing 40% sodium chlorate and 60% sodium pentaborate.[...]
The determination is based on the reaction of sodium chlorate with benzidine chloride in a sulfuric acid medium and subsequent photometric measurement of the optical density of the dye colored in yellow reaction product at 430 nm.[...]
Hydrazine is obtained by reacting ammonia with sodium chlorate.[...]
In the USA, the most widely used compounds are sodium chlorate and borates in a ratio of 1: 4.[...]
The method is selective. Substances accompanying the preparation of sodium chlorite (sodium chlorate, etc.) do not interfere with the determination.[...]
The absence of death of animals during the experiment allows us to classify sodium chlorate as a non-cumulative substance.[...]
Summarizing the results of subacute experience, we can conclude that sodium chlorate, when administered systematically, can cause an increase in the level of methemoglobinemia, but this increase is insignificant, although there are individual fluctuations. An increase in the level of methemoglobinemia under the influence of high doses (at the level of ’/3 0bbo) is not accompanied by a red blood cell reaction or hemolysis. There was no effect of chlorate on the general condition of the body or its growth.[...]
The ability to move through plant tissues has been established in sodium chlorate and ammonium sulfamate, although these drugs are toxic even when introduced into the soil.[...]
The study of conditioned reflex activity of rats under the influence of sodium chlorate was carried out using the method of developing temporary connections against the background of the action of chlorate in a Kotlyarevsky chamber with a Losev integrator. To select groups that are equivalent in their characteristics nervous activity, before priming, all rats developed a conditioned reflex to a positive sound signal (bell). In this case, the rate of emergence and strengthening of the conditioned reaction, the value of the latent period, the value of the conditioned and unconditioned reaction and the percentage of loss of the reflex were taken into account.[...]
Example 3. The oxidative delignification of aspen wood with sodium chlorate was studied in laboratory conditions. Wood in the form of chips was subjected to sequential oxidative treatment with a solution of sodium chlorate in the presence of hydrochloric acid and alkaline extraction with a solution of sodium hydroxide. Independent variables: X1 - concentration of sodium chlorate in solution, g/l (X!° = 50; = 6); X2 is the concentration of hydrochloric acid in the solution, g/l (X2° = 85; Ar = 15); Хз – temperature of oxidative treatment, °С (Хз°=70, Az=5); X4 - duration of oxidative treatment, min (X4°= 180; A4 = 30); X5 is the consumption of NaOH for extraction as a percentage of the original wood (X5° = 2.5; A5 = 0.5); Xa - extraction temperature, °C (X6° = 92; R6 = 8; X7 - extraction duration, min (X7° = 30; = 10). The output parameter in the example is the yield of solid residue as a percentage of the original wood. Variables X-, varied in accordance with the plan DFE ti-ia 27 3 (/a replica of PFE) with generating ratios: x5 = x, x3x4; x6 = x1x2x3; x7 = x.1x2x3x4. [...]
Experimental substantiation of the maximum permissible concentration of sodium chlorate in water bodies. V. T. Myzaev Experimental toxicological materials for the study of the complex action of chemical agents that simultaneously pollute water and air. S. M. Pavlenko Comparative assessment of the bromsulfalein test and other functional tests for the liver in conditions of subacute experimental hepatopathy. V. E. Miklashevsky, V. N. Tugarinova, I. A. Akundinova, A. N. Novikova, G. A. Savonicheva, G. G. Skobtsova.[...]
Summarizing the results of sanitary-toxicological studies, we can say that sodium chlorate is a substance characterized by relatively low toxicity and does not have cumulative properties. Systematic administration of it in high doses (up to 73 OB50) does not cause death of animals, but is manifested only by a slight increase in the amount of methemoglobin. Moreover, one day after the next administration of the substance, the amount of methemoglobin returns to normal. The latter fact indicates that in this case the body copes with the neutralization of the substance by the physiological mechanism of demethemoglobinization (K. S. Kosyakov, 1939).[...]
The difference in the obtained values practical significance does not have, and the concentration of Sodium chlorate 20 mg/l can be considered a threshold for the effect on the organoleptic properties of water.[...]
Forms of application. Borax is used both in pure form and in mixtures, especially with sodium chlorate, reducing the risk of ignition of the latter (for example, 9 parts of borax plus 1 part of chlorate for soil sterilization) (Grigsby V. H. et al, Mich.[... ]
The data obtained indicate that an aftertaste with an intensity of 1 point is imparted to water by sodium chlorate at a concentration of 21.9 mg/l at a temperature of 20° and at a concentration of 19 mg/l at a temperature of 60°. [...]
Salts of perchloric acid, in particular sodium chlorate, can be used as a general exterminator herbicide. It is used in doses of 300-500 kg per 1 ha with a water consumption of 1500-2000 liters per 1 ha. However, the use of this herbicide is limited due to its toxicity to humans and animals, as well as its explosiveness and ability to cause corrosion of metals. Sodium chlorate itself is safe for plants, but in plant tissues it turns into toxic compounds - chlorites and hypochlorites. To avoid the threat of explosion, use calcium chlorate and magnesium chlorate - non-explosives.[...]
Of some interest is the formation of chlorine dioxide during the reduction of sodium chlorate (NaC103) obtained by electrolysis with hydrochloric acid table salt at a temperature of 60°C.[...]
For the experiment, 20 white rats were taken (10 experimental, 10 control). The seeding was carried out at the rate of 73 Sbbo (2200 mg/kg) sodium chlorate daily for 30 days. Subsequently, the methemoglobin content was determined 4.6 hours and 1 day after the first inoculation, then on the 10th, 20th and 30th days of the experiment. Determination of methemoglobin one day after the start of the experiment was carried out before the administration of the next dose of sodium chlorate, subsequent determinations - 4-5 hours after the next administration of salt. [...]
When conducting a subacute toxicological experiment, we set the task, firstly, to study the ability of sodium chlorate to accumulate in the body, and secondly, to find out the characteristics of the influence of this substance when systematically introduced into the body in comparison with acute poisoning and, on the basis of this, select tests that were It would be advisable to test under conditions of a chronic sanitary-toxicological experiment.[...]
Initially, chemical weed control was used inorganic substances: copper sulfate, ferrous sulfate, sodium arsenite, sodium chlorate, sulfuric acid, etc. [...]
Figure 5 shows a technological scheme for producing CO2 using the Matheson method. Concentrated sulfuric acid and sodium chlorate solution are fed into the primary reactor. A mixture of 80g with air is pumped into the lower part of the reactor. The contents of the reactor are cooled to a temperature of 40 °C using a water jacket. Chlorine dioxide is purged from the solution with air and sent to an absorber, where it is absorbed by cooled water. The resulting chlorine dioxide solution is collected at the bottom of the absorber. Liquid from the primary reactor flows into the secondary reactor, where unreacted chlorate reacts with 80g. The spent liquid from the secondary reactor is purged with clean air to separate the remaining dissolved CO2 and pumped into a container for acidic reactor residue.[...]
Forms of application. To kill weeds, some specifications require a content of 98% NaCl3, but formulations are commercially available in which sodium chlorate is mixed with other salts, such as sodium chloride, to reduce flammability. [...]
This method eliminates the formation of chlorine as a by-product and significantly reduces the amount of sodium sulfate formed compared to other methods based on the use of sodium chlorate.[...]
Tests of desiccants in wheat crops carried out in the Primorsky Territory, Western Urals and other regions of the country showed that magnesium and calcium chlorates are the most effective. Of the large number of desiccants tested in Japan, sodium chlorate turned out to be the most acceptable. In many countries, reglon, which is a fast-acting effective drug, is being tested for this purpose, but in some cases small remnants of reglon (0.05-0.07 mg/kg) were found in grain. The drug was not detected in flour and bran.[...]
The liver, kidney and spleen of experimental animals were examined pathomorphologically. Moreover, only in some animals primed with sodium chlorate at a dose of 500 mg/kg, accumulations of macrophages filled with pigment granules were found in the spleen, giving positive reaction for iron using Pearls stain (hemosiderin). In animals receiving sodium chlorate at doses of 1 and 10 mg/kg, as well as in control animals, macrophages containing hemosiderin are not found in single units in all fields of view. In other organs, no morphological changes that could be attributed to the influence of sodium chlorate were noted. The data presented allow us to conclude that sodium chlorate, with chronic exposure at a dose of 500 mg/kg, can cause moderate hemolysis.[...]
The production of chlorine dioxide using the Holst method, first mastered in our country at the Bratsk Forestry Plant, occurs in one reactor, into which a solution of sulfuric acid and sodium chlorate from a diluent are periodically fed. The use of chlorate does not exceed 88-89%.[...]
It is easier to produce electrochemical whitewash using baths with diaphragms. In such baths, a solution of lead salt is obtained in the anode space, and a solution of caustic soda in the cathode space. In a special apparatus, anolyte and catholyte are mixed by passing carbon dioxide. In this case, lead white is deposited and sodium chlorate is regenerated.[...]
Warehouses are divided into categories according to the fire hazard of the materials they contain. Thus, category A includes: warehouses for flammable liquids, turpentine, sulfane odorant, varnish solvents, alcohol varnishes and nitro varnishes. Warehouses of liquid sodium chlorate and oxygen belong to category B. Warehouses of wood chips, reeds, straw, waste paper, rags and other flammable materials belong to category B, and warehouses of non-combustible materials - to category D.
