Stop mistaking sodium sulfide!

“What a hassle!” A man in antiseptic overalls tugged on his gas mask impatiently, “Hey, brother, this thing is highly poisonous, no matter how troublesome it is, you have to take all of these things with you!” Another The tall man stretched out his rubber gloved hand and patted the man on the shoulder. “But don’t tell me, this thing is selling really well. I ordered another batch of goods yesterday. When I get the money, my brother and I will go have a drink!”

Sodium Sulfide looked at the figures of the two people who were gradually going away, but the impatient expression of the man just now was in his mind, as if he had returned to the time when everyone avoided him a long time ago…

l Disliked sodium sulfide

“What is this! My hand, my hand hurts so much!”

“What is so stinky! Why does it smell like rotten eggs!”

Some people shouted loudly while holding their red and chapped hands, some people covered their noses and pointed, and the scene became a mess

Suddenly someone pointed to a pile of brown-red and khaki-yellow flakes and shouted: “This is it! It’s sodium sulfide!”

The sodium sulfide who was called by his name suddenly trembled, as if someone had poked a key point and dared not move.

When it was with other chemical ores before, it was a different kind of one. It knew that it was poisonous, or highly poisonous. It could only stay with other poisonous companions, and those who could not use it avoided it. , people who can use it will also find it too troublesome.

Sodium Sulfide looked at the crowd coming and going, and wanted to refute that it was really not scary, but once again looked at the “safety matters” posted on the wall.

Sodium sulfide lowered its head, how should it refute? Those people are right, it is indeed a very troublesome guy.

Be careful not to eat it by mistake, or even just the smell it emits, and sometimes you need to wear a gas mask; even a simple touch will cause redness and chapping because of its corrosiveness, so that all people who may come into contact with it Its personnel must wear rubber gloves and even wear anti-corrosion work clothes; in addition, care must be taken to avoid leakage and the treatment of production wastewater. If the dissolved and volatilized gas is not handled properly, the sulfide in the water is easy to hydrolyze, in the form of H2S Released into the air, nausea and vomiting immediately after being absorbed in a large amount by people, and even difficulty in breathing, suffocation, etc., resulting in a strong sense of toxicity. If it reaches 15-30mg/m3 in the air, it will cause inflammation of the eye membrane and damage to the optic nerve. H2S dissipated in the air is inhaled by people for a long time, and it will react with cytochrome, oxidase and disulfide bonds in human proteins and amino acids in the human body, affecting the oxidation process of cells, causing hypoxia in cells, and endangering human health. life. And if the waste water is not treated properly, resulting in long-term drinking of water with high sulfide content, it will cause dull taste, loss of appetite, weight loss, poor hair growth, and failure and death in severe cases.

Sodium Sulfide sighed, it turned out that he was really troublesome.

l Sodium sulfide: It is true that it is poisonous, and it is true that it is useful

“Sodium sulfide again.”

When I heard this sentence, sodium sulfide was relieved. It was about to start working. Compared with staying in a low-temperature and dry warehouse, it preferred to be soaked in water, dissolved, or mixed with other chemicals. The product has a wonderful reaction.

“Hey, kid. You’re pretty good. You have many uses, a wide range of fields, and high efficiency. No wonder there are so many people ordering.”

“Really? Am I really useful?”

Sodium Sulfide raised his head, his eyes were full of expectation, but his body was still shrunk in the corner, not daring to go forward.

“Of course, you see, you can make sulfur dyes in the dye industry, which can be the raw materials for sulfur cyan and sulfur blue; Hair removal; preparation of sodium polysulfide to accelerate dry skin soaking and softening is also indispensable; you are also used as a cooking agent for paper in the paper industry; denitrification and reduction of nitrates in the textile industry are also your role; mordant dyeing for cotton fabric dyeing agent; even in the pharmaceutical industry, it can be used to produce antipyretics such as phenacetin; not only these, you can also use it to make sodium thiosulfate, sodium hydrosulfide, sodium polysulfide, etc. These are all yours It works!”

Sodium sulfide thought about it for a long time that day. It is still useful, not only has shortcomings. Since it is troublesome, it should be used to its full potential. This is the best way and what it should do.

In the metallurgical industry, it can effectively remove impurity ions such as Cu2+, Pb2+, Zn2+, etc. in rare earth solutions. Studies have shown that controlling the pH at about 5 and adding Na2S to the rare earth eluate to remove impurities not only has a good effect of removing impurities, but also does not lose rare earths.

Or deal with mercury-containing wastewater that is extremely harmful to the environment and human health. In the soda making industry, the mercury content in the discharged wastewater is generally high, exceeding the international standard (0.05mg/L). In a weakly subtractive (pH 8-11) solution, mercury ions can form insoluble precipitates with sodium sulfide. It can be seen from the attached table that the solubility product of HgS is very small (Ksp=1.6×10-52). Through the research, it is determined that the treatment effect is the best when the amount of Na2S is constant and the pH value is controlled at 9-10, and the Hg2+ in the wastewater can be reduced to below the national standard (0.05mg/L). In addition, by adding FeSO4 to generate Fe(OH)2 and Fe(OH)3 colloids in water, these colloids can not only adsorb mercury ions, but also trap and coat suspended HgS solid particles, playing a good role in coagulation and precipitation . The sediment is not easy to be polluted twice and is convenient for disposal.

It can also be used to remove arsenic. It should be known that arsenic generally exists in minerals in the form of sulfide. During the pyro-smelting process, most of the arsenic volatilizes into the flue gas and dust, especially the direct emission of low-concentration SO2 will pollute the environment. Therefore, arsenic removal should be performed before flue gas subsequent treatment or emptying. Use Na2S solution to absorb SO2 flue gas, so that As3+ and S2- form As2S3 precipitate (Ksp=2.1×10-22), at a higher pH (pH>8), As2S3 can be dissolved to form As3S3-6 or AsS2-3, compared with At low pH, the solution will generate H2S gas. The research of Yin Aijun et al. [4] shows that when the pH of the solution is controlled in the range of 2.0 to 5.5, the reaction time is 50 minutes, the reaction temperature is 30 to 50°C, and the flocculant is added, the arsenic removal rate can reach 90%. %above. In the production of medicinal white carbon black, in order to reduce the content of impurity arsenic in the concentrated sulfuric acid of the production raw material, sodium sulfide is added to the concentrated sulfuric acid to make As3+ form As2S3 and precipitate and remove it. Production practice shows that sodium sulfide removes arsenic not only with fast reaction speed, but also with complete removal of arsenic. The content of arsenic in sulfuric acid after removing arsenic is less than 0.5×10-6, and the arsenic content of white carbon black produced with this raw material is ≤0.0003%, which fully complies with relevant regulations.

It also plays a big role in electroplating!

First, it acts as a brightener. Sodium sulfide is dissolved in water and ionized into positively charged sodium ions (Na+) and negatively charged sulfide ions (S2-). During the electroplating process, the presence of S2- in the electrolyte can promote cathode polarization. At the same current Under this condition, the cathode reaction speed is accelerated. The deposition speed is also accelerated, the deep plating ability is increased, the coating is refined, and the surface of the plated part becomes brighter correspondingly.

It can also remove impurities in the electrolyte, mainly because during the electroplating production process, more or less impurities in the raw materials will be brought into the plating solution. These impurities react differently under the action of the electrodes, and the impurities with lower potential will be deposited on the surface of the plated part together with Zn2+, affecting the quality of the plated layer. After adding sodium sulfide, S2- in sodium sulfide can form precipitates with metal impurity ions, preventing impurities from participating in electrochemical reactions and making the coating bright.

Or use sodium sulfide solution for flue gas desulfurization. The recovery method of SO2 in flue gas is mainly to convert SO2 into H2SO4, liquid SO2 and elemental sulfur. Elemental sulfur is also an ideal product for recycling due to its ease of handling and transportation. A new process for producing elemental sulfur by using H2S produced from Na2S solution as a reducing agent to reduce SO2. This process is simple and does not need to consume expensive reducing agents such as natural gas and low-sulfur coal like general production technologies. When the pH of the solution drops to 8.5-7.5, absorbing SO2 with Na2S will produce H2S, and H2S and SO2 will undergo wet Claus reaction in the liquid phase.

In addition, sodium sulfide can be used as an inhibitor to help beneficiation. As long as there are two aspects, one is that Na2S is hydrolyzed to produce HS-, and HS- excludes xanthate adsorbed on the surface of sulfide minerals, and at the same time, it is adsorbed on the surface of minerals to increase the hydrophilicity of mineral surfaces; on the other hand, it is believed that Na2S plays an inhibitory role not only It is caused by the adsorption of HS- on the mineral surface, and it should also be related to the S2- generated by the ionization of Na2S in aqueous solution.

Due to the large solubility product of PbS and the small solubility product of PbX2, when Na2S is added, the concentration of S2- increases, and the balance shifts to the left, which makes the xanthate attached to the mineral surface desorb, so that Na2S can inhibit the mineral surface effect. Utilizing the inhibitory effect of Na2S, the flotation of Ni2S3 can be inhibited by adding Na2S, so that the effective separation of Cu2S and Ni2S3 in high nickel matte can be realized. In some lead-zinc beneficiation plants, due to equipment problems and unreasonable production processes, the slag after flotation still contains relatively high lead and zinc. However, due to the adsorption of certain flotation agents on its surface, long-term stacking will cause serious muddying, which will cause great difficulty in the re-separation of lead-zinc middle ore. Utilizing the inhibitory effect of Na2S, Na2S can be used as a reagent to desorb the xanthate that has been adsorbed on the mineral surface, so that the subsequent flotation operation is easy to carry out. The lead-zinc medium ore stockpiled in Shaanxi Xinhe Concentrator was pretreated with sodium sulfide for drug removal, and then flotation was carried out to obtain lead concentrate with a lead content of 63.23% and zinc concentrate with a zinc content of 55.89% (lead and The recovery rate of zinc can reach 60.56% and 85.55% respectively), which makes full use of secondary mineral resources. In the sorting of copper-zinc sulfide ores, due to the dense symbiosis of minerals, sulfur content and high secondary copper, it is difficult to sort. This kind of ore has been activated by Cu2+ during the grinding process, and its floatability It is close to chalcopyrite, so copper and zinc minerals are not easy to separate. When processing this kind of ore, by adding Na2S during ore grinding, the S2- produced by the hydrolysis of Na2S and some heavy metal ions with activation ability, such as Cu2+, form insoluble sulfide precipitates to remove the activation of these heavy metal ions. Then, by adding zinc and sulfur inhibitors, using butyl ammonium black drug to preferentially select copper-copper tailings for zinc selection-zinc tailings for sulfur separation to obtain copper concentrate with 25.10% copper and zinc concentrate with 41.20% zinc ore and sulfur concentrate with a sulfur content of 38.96%.

When sodium sulfide is used as an activator, FeS film can be formed on the surface of limonite. Because at higher pH, FeS film can increase the adsorption of molecular amines, so FeS reagent particles can be used for flotation at high pH. Amine flotation of limonite. In addition, Na2S can be used as a flotation activator for copper oxide minerals. When an appropriate amount of Na2S is added to the flotation solution, the dissociated S2- undergoes a displacement reaction with the lattice anions on the surface of the oxidized mineral to form a sulfide film on the surface of the copper oxide mineral, which is beneficial to the adsorption of xanthate collectors. However, the copper sulfide film formed on the surface of the copper oxide ore is not very firm, and it is easy to fall off when the stirring is strong. When dealing with the Totozui copper mine in Daye, Hubei (copper-containing minerals mainly composed of malachite), the flotation method of adding Na2S in multiple stages and extracting the concentrate at multiple points reduces the circulation of the middle ore, and the copper concentrate grade ratio The production process has been improved by 2.1%, and the copper and gold recovery rates have increased by 25.98% and 10.81% respectively. Na2S can also be used as a flotation activator for pyrite suppressed by peralkali lime in a perkalime system. In the high alkali system, the surface of pyrite is covered with hydrophilic calcium film (Ca(OH)2, CaSO4), which inhibits its flotation. Studies have shown that after adding Na2S, the hydrolyzed HS- ions can squeeze out Ca(OH)2, CaSO4 and Fe(OH)3 covering the surface of pyrite on the one hand, and at the same time, it can be adsorbed on the surface of pyrite. . Because pyrite has the ability to transfer electrons, when the interface potential of pyrite is greater than EHS/S0, HS- loses electrons on the surface of xanthate to generate hydrophobic elemental sulfur. The resulting elemental sulfur coats the surface of the mineral, thereby activating it for easy flotation.

When used as an induced flotation agent for gold and silver minerals, since the collector-free flotation of gold ores makes full use of the electrochemical principle and the electronic difference between the sulfide and gold-silver mineral surfaces, the collector-free flotation has more advantages. High selectivity, simpler pharmaceutical system. In addition, it eliminates the non-selective adsorption that is difficult to control in the flotation of xanthate collectors, and solves the problem of drug removal before cyanide leaching gold and the problem of collector film barrier gold leaching. Therefore, in recent years, the There are many studies on the flotation of gold and silver minerals without recovery agents. Gold and sulfide minerals in gold and silver ores often coexist, especially gold and pyrite are closely dependent. Because the surface of pyrite has semiconductor properties and certain electron transport ability, and, through the comparison of the surface electrostatic potential of pyrite with HS-/S0 to EHS-/S0, when the pH of the ore slurry is in the range of 8-13, pyrite The electrostatic potential of the mine surface is always higher than EHS-/S0. Therefore, the HS- and S2- ionized by Na2S in the pulp will discharge on the pyrite surface to generate elemental sulfur.

In the leather industry, sodium sulfide is more widely used.

Mainly use the ash-alkali combination method to remove the fiber interstitium in the skin, weaken the connection between the hair, epidermis and dermis, modify the elastic fiber, destroy the muscle tissue, and benefit the effect of other materials in the subsequent process on the skin; saponify the oil in the bare skin , to remove part of the oil in the skin and help degreasing; to open the secondary bonds of the collagen part, so that the collagen fibers can be properly loosened and release more collagen active groups; and to remove the coat and epidermis (alkali rotten hair) .

Not to mention the sulfur dyes that have a history of more than one hundred years. The production of dyestuffs is mainly achieved through two production methods: baking method and boiling method.

Sulfur dyes are reduced and dissolved to form a dye solution, and the formed leucosomes are absorbed by the cellulose fibers, and after air oxidation treatment, the cellulose fibers show the desired color.

The matrix of sulfur dyes has no affinity for fibers, and its structure contains sulfur bonds, disulfide bonds or polysulfide bonds, which are reduced to sulfhydryl groups under the action of sodium sulfide reducing agent and become water-soluble leucosome sodium salts. The reason why leucosomes have a good affinity for cellulose fibers is that the molecules of the dyes are relatively large, which in turn produces greater Van der Waals force and hydrogen bonding forces with the fibers.

At this time, sodium sulfide production can also be subdivided into four types: powder vulcanization, water-soluble vulcanization, liquid vulcanization, environment-friendly vulcanization, sulfur reduction and dispersed vulcanization.

1. Powder vulcanization

The general structural formula of the dye is D-S-S-D, and generally needs to be boiled with sodium sulfide and applied after dissolving. This kind of dye is insoluble in water, the dye can be reduced to leuco with alkaline reducing agent, and dissolved in water, the sodium salt of leuco can be absorbed by the fiber

2. Water-soluble vulcanization

The general formula of the dye structure is D-SSO3Na. The characteristic of this kind of dye is that there are water-soluble groups in the molecular structure of the dye, which has good solubility and good level dyeing property. React ordinary sulfur dyes with sodium sulfite or sodium bisulfite to generate dye thiosulfate, which has a solubility of 150g/L at 20°C and is used for continuous dyeing. Water-soluble sulfur dyes dissolve quickly at room temperature, there is no insoluble matter, and the saturated solubility is sufficient to meet all the dissolution requirements of dyeing dosage. Water-soluble sulfur dyes have excellent high temperature resistance. However, the dye does not contain a reducing agent and has no affinity for fibers. It is necessary to add alkali sulfide during dyeing, and convert it into a state that has affinity for cellulose fibers through nucleophilic and reduction reactions. Generally, it is applied to textiles by means of suspension pad dyeing.

3. Liquid vulcanization

The general structural formula of the dye is D-SNa, which contains a certain amount of sodium sulfide reducing agent to pre-reduce the dye to a water-soluble leuco. Reducing common sulfur dyes to water-soluble leuco with reducing agent, adding excess reducing agent as antioxidant, adding penetrating agent, inorganic salt and water softener to make liquid dye, also known as pre-reduced dye. It can be used directly by diluting with water. Such dyes include sulfur-containing dyes, such as Casulfon dyes containing sodium sulfide, and also contain no or very small amounts of sulfur, such as Immedial dyes, and there is no sulfur-containing waste water during dyeing.

4. Environmentally friendly vulcanization

In the production process, it is refined into leucochrome, but the sulfur content and polysulfide content are far lower than ordinary sulfur dyes. The dye has high purity, stable reducibility, and good permeability. At the same time, glucose and sodium hydrosulfite are used as binary reducing agents in the dye bath, which can not only reduce sulfur dyes, but also play an environmental role.

5. Sulfur reduction

Often made into powder, fine, ultrafine powder or liquid dyes, suitable for polyester-cotton blended fabrics and disperse dyes in the same bath dyeing, can be used for reduction of caustic soda, sodium hydrosulfite (or thiourea dioxide), instead of sodium sulfide for reduction and dissolution, such as Hydron Indocarbon dye.

6. Dispersion vulcanization

Disperse sulfur dyes are based on sulfur dyes and sulfur vat dyes, and are produced according to the commercial processing method of disperse dyes. They are mainly used for pad dyeing polyester-viscose or polyester-cotton blended fabrics with disperse dyes in the same bath. There are 16 varieties of Kayaku Homodye produced by Nippon Kayaku.

The specific dyeing process can be divided into four steps

(1) Reduction of dyes It is easier to dissolve sulfur dyes. Sodium sulfide is commonly used as a reducing agent, and it also acts as an alkali agent. In order to prevent the leuco body from being hydrolyzed, soda ash and other substances can be added appropriately, but the alkalinity of the reduction bath should not be too strong, otherwise the dye reduction rate will slow down.

(2) The dye leuco in the dye solution is absorbed by the fiber. The leuco of the sulfur dye exists in the anion state in the dye solution. It has directness to the cellulose fiber and can be adsorbed on the surface of the fiber and diffused into the interior of the fiber. Sulfur dye leuco has low directness to cellulose fiber, generally adopts small bath ratio, and adds appropriate electrolyte at the same time, can increase dyeing rate at higher temperature, and improve level dyeing and penetration.

(3) Oxidation treatment After the sulfur dye leuco is dyed on the fiber, it must be oxidized to show the desired color. Oxidation is an important step after dyeing with sulfur dyes. After dyeing, easily oxidized sulfur dyes can be oxidized by air after washing and ventilating, that is, the air oxidation method is used; for some sulfur dyes that are not easily oxidized, oxidizing agents are used to promote oxidation.

(4) Post-processing Post-processing includes cleaning, oiling, anti-brittleness and color fixation, etc. Sulfur dyes must be fully washed after dyeing to reduce the residual sulfur on the fabric and prevent the fabric from being brittle, because the sulfur in the dye and the sulfur in the vulcanized alkali are easily oxidized in the air to form sulfuric acid, which will cause acid hydrolysis to the cellulose fiber and cause damage. Reduce the strength and make the fiber brittle. Therefore, it can be treated with anti-brittle agents, such as: urea, trisodium phosphate, bone glue, sodium acetate, etc. In order to improve the sunlight and soaping fastness of sulfur dyes, it can be fixed after dyeing. There are two methods of color fixing treatment: metal salt treatment (such as potassium dichromate, copper sulfate, copper acetate and mixtures of these salts) and cationic color fixing agent treatment (such as color fixing agent Y). In production, it is better to use color-fixing agent M, which is compounded by cationic color-fixing agent and copper salt, which can reduce chromium pollution.

l Sodium sulfide: Please pay attention to these when using!

“Do you feel sad because you are troublesome?”

Sodium Sulfide nodded but did not speak, but the voice sounded again

“But, that’s fine.”

Sodium sulfide looked at the man, who was wearing anti-corrosion overalls, a gas mask and rubber gloves

“Look, these are very simple and not troublesome at all.”

“No, it’s very troublesome. You have to wear anti-corrosion work clothes, a gas mask, and rubber gloves. Ordinary things are useless. You have a lot of precautions. If you are not careful, you will be injured. You have to deal with them during use. waste gas and waste water.”

“However, I have a solution. I don’t have to be injured, and I can solve it very well.

If I accidentally spill it on my clothes, I just need to take off the contaminated clothes immediately, rinse with plenty of running water for at least 15 minutes and then go to the doctor; if I accidentally touch the eyes, I can immediately lift the eyelids and wash with plenty of running water Or normal saline rinse thoroughly for at least 15 minutes before seeking medical attention; if accidentally inhaled, I will quickly leave the scene and go to a place with fresh air to keep the airway unobstructed. If breathing is difficult, contact oxygen again. If breathing stops, perform artificial respiration immediately and seek medical attention; if accidentally swallowed, I will rinse mouth with water, drink milk or egg white, and then seek medical attention. “

“But I’m still flammable!”

“I know, you are a spontaneous combustion substance in an anhydrous state, and the dust is easy to spontaneously combust in the air. It will decompose when it encounters acid and release flammable gases. It can also form explosive mixtures when it is in powder form, and the aqueous solution is also corrosive and extremely toxic. Strong irritant. At 100°C you start to evaporate, and the steam can attack glass.”

Hearing this, Na Su felt even more sad. The head that had been raised just now had already drooped, not daring to look at the speaker again.

“But it doesn’t matter, as long as water, mist water, and sand can extinguish the fire. If there is a leak, isolate the contaminated area, put on a full-face mask and anti-acid and alkali work clothes and enter the scene from the upper wind. The shovel is collected in a dry, clean, covered container, or rinsed with a large amount of water, diluted and then put into the wastewater system. If it is a large-scale leak, it can only be collected and recycled or transported to a waste disposal site for disposal. But these are all It is the knowledge we have learned in advance, and the employees of our company have undergone professional and systematic learning and training so that no leaks will occur. Don’t worry, let alone feel guilty, it’s not your fault!”

After a while, Sodium Sulfide raised his head and said: “But you must be careful! Even if you have learned this, you also have to be careful, it’s really dangerous for using me.”

l Sodium sulfide: If you want to take me out, please pay attention!

“Pack up and transport the sodium sulfide away today. You know all the precautions. You know the specifications and packaging!”

“Yeah!”

For a while, the factory began to get busy.

Sodium sulfide is tightly sealed in 0.5 mm thick steel drums, and the net weight of each drum does not exceed 100 kg. After packing, it was loaded on the gondola.

Railway security inspectors assemble dangerous goods in accordance with the dangerous goods assembly table in the Ministry of Railways’ “Dangerous Goods Transport Rules”. At the time of shipment, the staff strictly checked the integrity and safety of the packaging, and also ensured that it was not mixed with oxidants, acids, food chemicals, etc. In addition, the vehicle is also equipped with corresponding types and quantities of fire-fighting equipment and leakage emergency treatment equipment.

While in the car, Na S could not help but think of what someone said to him before departure

He said, “You may think that you are highly poisonous and corrosive, but you have to know that you have many uses, and we will also tell the person who picks you up what he should pay attention to. All you need to do is to be careful. Play your role, let our care be worthwhile, let us see your strength, this is enough.”

When Sodium Sulfide stays in the low-temperature and dry warehouse again, it will still yearn to be soaked in water, but it no longer feels bored, but can’t wait to help its new owner finish the work!

Do you really know about sodium sulfide?

As we all know, sodium sulfide is highly toxic and corrosive, but it is widely used in many fields, so do you really understand the relevant information about sodium sulfide?

l Overview of sodium sulfide

Pure sodium sulfide is a colorless crystalline powder with strong hygroscopicity and is easily soluble in water. The aqueous solution has a strong alkaline reaction and will cause burns when it touches the skin and hair, so sodium sulfide is also called alkali sulfide. Sodium sulfide aqueous solution will slowly oxidize into sodium thiosulfate, sodium sulfite, sodium sulfate and sodium polysulfide in air. The color of industrial sodium sulfide is pink, brownish red, and khaki due to impurities. Yellow flaky sodium sulfide with hydrogen sulfide odor and hygroscopicity. It turns yellow to brown-black when exposed to light and in the air, and gradually produces hydrogen sulfide, which can be decomposed when encountering acid or even carbonic acid. It is easily soluble in water, slightly soluble in ethanol, and insoluble in ether. The aqueous solution is alkaline, and the solution will gradually become sodium thiosulfate and sodium hydroxide when placed in the air.

The development of sodium sulfide in my country has a long history and rich experience. The production of sodium sulfide originated in the 1830s, and a small-scale production was first started by a chemical factory in Dalian, Liaoning. From the 1980s to the mid-1990s, with the vigorous development of the international chemical industry, the domestic sodium sulfide industry has undergone fundamental changes. The number of manufacturers and scale has increased dramatically, and the development is rapid. The sodium sulfide production area centered in Yuncheng, Shanxi has rapidly expanded to more than 10 provinces and regions including Yunnan, Xinjiang, Inner Mongolia, Gansu, Qinghai, Ningxia, and Shaanxi. The national annual production capacity soared from 420,000 tons in the late 1980s to 640,000 tons in the mid-1990s. Its output develops fastest in Inner Mongolia, Gansu, and Xinjiang in Northwest China. The production capacity of Inner Mongolia has reached 200,000 tons, and it has become the largest production base of sodium sulfide products in China.

Since our company started to contact sodium sulfide products, we have reached cooperation with many companies and have received extremely high evaluations. We can guarantee product quality and transportation and other matters, “quality service”, “product first” and “customer first” It is the principle we have always adhered to!

l Application of sodium sulfide:

1. The dye industry is used to produce sulfur dyes, and is the raw material for sulfur blue and sulfur blue.

2. In the printing and dyeing industry, it is used as a dyeing aid for dissolving sulfur dyes.

3. In the paper industry, it is used as a cooking agent for paper.

4. In the textile industry, it is used in the denitrification of man-made fibers and the reduction of nitrates, and as a mordant for cotton fabric dyeing.

5. In the tanning industry, it is used for hydrolysis to depilate raw hides, and it is also used to prepare sodium polysulfide to accelerate the soaking of dry hides and soften them.

6. The electroplating industry is used for the treatment of the conductive layer in direct electroplating, through the reaction of sodium sulfide and palladium to form colloidal palladium sulfide to achieve the purpose of forming a good conductive layer on the non-metallic surface.

7. The pharmaceutical industry is used to produce antipyretics such as phenacetin.

8. There are also certain uses in the military industry.

9. In mineral flotation, sodium sulfide is the inhibitor of most sulfide ores, the sulfide agent of non-ferrous metal oxide ores, and the deagent of mixed concentrates of sulfide ores.

10. In water treatment, it is mainly used to treat electroplating or other wastewater containing metal ions, and use sulfur ions to precipitate metal ions to remove metal ions, such as germanium, tin, lead, silver, cadmium, copper, mercury, zinc, manganese wait. The sodium sulfide precipitation method can recover valuable metal elements in heavy metal wastewater.

11. Adding an appropriate amount of sodium sulfide to the alkaline etching solution of aluminum and alloys can significantly improve the quality of the etched surface, and it can also be used to remove alkali-soluble heavy metal impurities such as zinc in the alkaline etching solution.

12. It is the raw material of sodium thiosulfate, sodium polysulfide, sulfur dyes, etc.

13. Analyze water hardness in nitrogen fertilizer production.

Details:

Metallurgical Industry:

1) Removal of impurities in rare earth leachate When dealing with weathering crust elution-type rare earth ores, after leaching and leaching with a strong electrolyte solution, the rare earth leachate obtained often contains a large amount of impurity ions, such as Al3+, Fe3+, Ca2+, Mg2+, Cu2+, etc. When the oxalic acid precipitation process is used, these impurities will inevitably form oxalate precipitation and transfer to rare earth products, affecting the purity of the product. Moreover, in order to avoid emulsification in the subsequent extraction process, the impurity ions in the feed liquid must be removed first. The solubility product constants of several metal sulfide precipitates are shown in the attached table. When Na2S is added to the rare earth eluate, heavy metal ions Cu2+, Pb2+, Zn2+, etc. in the solution can be effectively removed. Studies have shown that controlling the pH at about 5 and adding Na2S to the rare earth eluate to remove impurities not only has a good effect of removing impurities, but also does not lose rare earths.

2) Use Na2S to remove arsenic. Arsenic generally exists in minerals in the form of sulfide. During the pyrometallurgy process, most of the arsenic volatilizes into flue gas and dust, especially the direct emission of low-concentration SO2 will pollute the environment. Therefore, arsenic removal should be performed before flue gas subsequent treatment or emptying. Use Na2S solution to absorb SO2 flue gas, so that As3+ and S2- form As2S3 precipitate (Ksp=2.1×10-22), at a higher pH (pH>8), As2S3 can be dissolved to form As3S3-6 or AsS2-3, compared with At low pH, the solution will generate H2S gas. The research of Yin Aijun et al. [4] shows that when the pH of the solution is controlled in the range of 2.0 to 5.5, the reaction time is 50 minutes, the reaction temperature is 30 to 50°C, and the flocculant is added, the arsenic removal rate can reach 90%. %above. In the production of medicinal white carbon black, in order to reduce the content of impurity arsenic in the concentrated sulfuric acid of the production raw material, sodium sulfide is added to the concentrated sulfuric acid to make As3+ form As2S3 and precipitate and remove it. Production practice shows that sodium sulfide removes arsenic not only with fast reaction speed, but also with complete removal of arsenic. The content of arsenic in sulfuric acid after removing arsenic is less than 0.5×10-6, and the arsenic content of white carbon black produced with this raw material is ≤0.0003%, which fully complies with the regulations of the United States Pharmacopoeia.

Water treatment:

It is mainly to deal with mercury-containing wastewater that is extremely harmful to the environment and human health. In the soda making industry, the mercury content in the discharged wastewater is generally high, exceeding the international standard (0.05mg/L). In a weakly subtractive (pH 8-11) solution, mercury ions can form insoluble precipitates with sodium sulfide. It can be seen from the attached table that the solubility product of HgS is very small (Ksp=1.6×10-52). Through the research, it is determined that the treatment effect is the best when the amount of Na2S is constant and the pH value is controlled at 9-10, and the Hg2+ in the wastewater can be reduced to below the national standard (0.05mg/L). In addition, by adding FeSO4 to generate Fe(OH)2 and Fe(OH)3 colloids in water, these colloids can not only adsorb mercury ions, but also trap and coat suspended HgS solid particles, playing a good role in coagulation and precipitation . The sediment is not easy to be polluted twice and is convenient for disposal.

Electroplating industry:

1) Na2S is used as a brightener in electroplating:

Sodium sulfide is dissolved in water and ionized into positively charged sodium ions (Na+) and negatively charged sulfide ions (S2-). During the electroplating process, the presence of S2- in the electrolyte can promote cathode polarization. At the same current Under this condition, the cathode reaction speed is accelerated. The deposition speed is also accelerated, the deep plating ability is increased, the coating is refined, and the surface of the plated part becomes brighter correspondingly.

2) Sodium sulfide removes impurities in the electrolyte:

During the electroplating production process, more or less impurities in the raw materials will be brought into the plating solution. These impurities react differently under the action of the electrodes, and the impurities with lower potential will be deposited on the surface of the plated part together with Zn2+, affecting the quality of the plated layer. After adding sodium sulfide, S2- in sodium sulfide can form precipitates with metal impurity ions, preventing impurities from participating in electrochemical reactions and making the coating bright.

3) Using Na2S solution for flue gas desulfurization

At present, the recovery method of SO2 in flue gas is mainly to convert SO2 into H2SO4, liquid SO2 and elemental sulfur. Elemental sulfur is also an ideal product for recycling due to its ease of handling and transportation. A new process for producing elemental sulfur by using H2S produced from Na2S solution as a reducing agent to reduce SO2. This process is simple and does not need to consume expensive reducing agents such as natural gas and low-sulfur coal like general production technologies. When the pH of the solution drops to 8.5-7.5, absorbing SO2 with Na2S will produce H2S, and H2S and SO2 will undergo wet Claus reaction in the liquid phase.

Mineral processing industry:

1) Sodium sulfide as inhibitor:

The inhibitory effect of sodium sulfide on sulfide ore is generally believed to be mainly due to two aspects. One is that Na2S hydrolyzes to produce HS-, HS- excludes xanthate adsorbed on the surface of sulfide minerals, and at the same time, it is adsorbed on the mineral surface to increase the hydrophilicity of the mineral surface; the other is On the one hand, it is considered that the inhibitory effect of Na2S is not only caused by the adsorption of HS- on the mineral surface, but also related to the S2- formed by the ionization of Na2S in aqueous solution.

2) Sodium sulfide as activator:

The flotation studies of smithsonite-limonite system showed that in limonite amine flotation, only at lower pH, amine could be adsorbed on the mineral surface by electrostatic force. However, after adding Na2S, a FeS film is formed on the surface of the limonite. Since the FeS film can increase the adsorption of molecular amines at a higher pH, the FeS reagent particles can be used for flotation, and the limonite can be depleted at a high pH. Amine flotation was performed. In addition, Na2S can be used as a flotation activator for copper oxide minerals. When an appropriate amount of Na2S is added to the flotation solution, the dissociated S2- undergoes a displacement reaction with the lattice anions on the surface of the oxidized mineral to form a sulfide film on the surface of the copper oxide mineral, which is beneficial to the adsorption of xanthate collectors. However, the copper sulfide film formed on the surface of the copper oxide ore is not very firm, and it is easy to fall off when the stirring is strong. When dealing with the Totozui copper mine in Daye, Hubei (copper-containing minerals mainly composed of malachite), the flotation method of adding Na2S in multiple stages and extracting the concentrate at multiple points reduces the circulation of the middle ore, and the copper concentrate grade ratio The production process has been improved by 2.1%, and the copper and gold recovery rates have increased by 25.98% and 10.81% respectively. Na2S can also be used as a flotation activator for pyrite suppressed by peralkali lime in a perkalime system. In the high alkali system, the surface of pyrite is covered with hydrophilic calcium film (Ca(OH)2, CaSO4), which inhibits its flotation. Studies have shown that after adding Na2S, the hydrolyzed HS- ions can squeeze out Ca(OH)2, CaSO4 and Fe(OH)3 covering the surface of pyrite on the one hand, and at the same time, it can be adsorbed on the surface of pyrite. . Because pyrite has the ability to transfer electrons, when the interface potential of pyrite is greater than EHS/S0, HS- loses electrons on the surface of xanthate to generate hydrophobic elemental sulfur. The resulting elemental sulfur coats the surface of the mineral, thereby activating it for easy flotation.

3) Sodium sulfide is used as an induced flotation agent for gold and silver minerals:

Since the collector-free flotation of gold ore makes full use of the electrochemical principle and the electron difference on the surface of sulfide and gold-silver minerals, the collector-free flotation has higher selectivity and simpler reagent system. In addition, it eliminates the non-selective adsorption that is difficult to control in the flotation of xanthate collectors, and solves the problem of drug removal before cyanide leaching gold and the problem of collector film barrier gold leaching. Therefore, in recent years, the There are many studies on the flotation of gold and silver minerals without recovery agents. Gold and sulfide minerals in gold and silver ores often coexist, especially gold and pyrite are closely dependent. Because the surface of pyrite has semiconductor properties and certain electron transport ability, and, through the comparison of the surface electrostatic potential of pyrite with HS-/S0 to EHS-/S0, when the pH of the ore slurry is in the range of 8-13, pyrite The electrostatic potential of the mine surface is always higher than EHS-/S0. Therefore, the HS- and S2- ionized by Na2S in the pulp will discharge on the pyrite surface to generate elemental sulfur.

Leather industry:

Using the gray-alkali combination method:

(1) Pure lime alkali method: combination of sodium sulfide and lime;

(2) Alkali-alkali method: a combination of sodium sulfide, caustic soda, and slaked lime (mostly used for liming of buffalo leather and pigskin). Due to the strong alkalinity of caustic soda, the current tanning production is basically not only for the production of pig leather, but also for liming. Use less caustic soda;

(3) Lime-alkali-salt method: on the basis of pure ash-alkali method, add neutral salts, such as calcium chloride, sodium chloride, sodium sulfate, etc.;

(4) Enzymatic liming.

To:

1. Remove the interdermal fibrous matrix, weaken the connection between hair, epidermis and dermis, modify elastic fibers, destroy muscle tissue, and benefit the effect of other materials on the skin in the subsequent process;

2. Saponify the oil in the bare skin, remove part of the oil in the skin, and play a certain role in degreasing;

3. Open the secondary bonds of the collagen part, so that the collagen fibers are properly loosened and more collagen active groups are released;

4. Remove the coat and cuticle (alkali rotten hair).

Dye industry:

Sulfur dyes have a history of more than 100 years since their birth. The first sulfur dyes were produced by Croissant and Bretonniere in 1873. They combined materials containing organic fibers, such as wood chips, humus, bran, waste cotton and waste Paper, etc. are obtained by heating with alkali sulfide and polysulfide. This dark, foul-smelling hygroscopic dye has an unstable composition and is easily soluble in water. When dyeing cotton with an alkaline bath and an alkali sulfide bath, a green dye is obtained. Cotton can turn brown when exposed to air or chemically oxidized with a dichromate solution to fix the color. Because these dyes have excellent dyeing performance and low price, they can be used in the cotton dyeing industry.

In 1893, R.Vikal melted p-aminophenol with sodium sulfide and sulfur to make black sulfur dyes. He also found that some benzene and naphthalene derivatives could be melted with sulfur and sodium sulfide to produce a variety of black sulfur dyes. dye. Since then, people have developed blue, red and green sulfur dyes on this basis. At the same time, the preparation method and dyeing process have also been greatly improved. Water-soluble sulfur dyes, liquid sulfur dyes and environmentally friendly sulfur dyes have appeared one after another, making sulfur dyes get flourishing.

Sulfur dyes are currently one of the most widely used dyes. According to reports, the output of sulfur dyes in the world reaches more than 100,000 tons, and the most important species is sulfur black dyes. At present, the output of sulfur black accounts for 75%~85% of the total output of sulfur dyes. Because of its simple synthesis, low cost, good fastness and no carcinogenicity, it is favored by printing and dyeing manufacturers. It is widely used in the dyeing of cotton and other cellulose fibers, and black and blue series are the most widely used.

There are two methods of industrial production of sulfur dyes:

1) Baking method, baking amines, phenols or nitro compounds of raw aromatic hydrocarbons with sulfur or sodium polysulfide at high temperature to prepare yellow, orange and brown sulfur dyes.

2) Boiling method, heat and boil the amines, phenols or nitro compounds of raw aromatic hydrocarbons and sodium polysulfide in water or organic solvents to prepare black, blue and green sulfur dyes.

Classification

1) Powder vulcanization

2) Water-soluble vulcanization

3) Liquid vulcanization

4) Environmentally friendly vulcanization

5) Sulfur reduction

6) Dispersion vulcanization

Structural Dyeing Mechanism

Sulfur dyes are a kind of sulfur-containing dyes. The molecule contains sulfur bonds composed of two or more sulfur atoms. When applied, it is reduced to a leuco body, so that it can be dissolved in water and dye the fiber. The characteristics of sulfur dyeing vary with the type of dye. Sulfur dyes have high washing fastness and strong applicability. Although the rubbing fastness and vividness are not as good as reactive dyes, their staining fastness and light fastness are better than reactive dyes, and sulfur dyes use less salt and consume less water when dyeing. few. Sulfur dyes are organic compounds containing nitro and amino groups, most of which are formed by reacting with sulfur and sodium sulfide at high temperature. Many sulfur dyes do not have a definite chemical formula. The dyeing principle of sulfur dyes is similar to that of vat dyes. They form water-soluble leucosomes that have affinity with fibers to dye fibers through chemical reduction reactions, and then bind tightly to fibers through oxidation.

Sulfur dyes are insoluble in water, and sodium sulfide or other reducing agents are required to reduce the dyes to soluble leucosomes during dyeing. It has an affinity to the fiber and dyes the fiber, and then restores its insoluble state after oxidation and color development and fixes on the fiber. So sulfur dye is also a kind of vat dye. Sulfur dyes can be used for dyeing cotton, linen, viscose and other fibers. The manufacturing process is relatively simple, the cost is low, and it can dye single color or mixed colors. It has good light fastness and poor wear fastness. There is a lack of red and purple in the color spectrum, and the color is darker, suitable for dyeing thick colors.

Dyeing mechanism

Process:

The dyeing process can be divided into the following four steps:

1) Reduction of dyes It is relatively easy to dissolve sulfur dyes. Sodium sulfide is commonly used as a reducing agent, and it also acts as an alkali agent. In order to prevent the leuco body from being hydrolyzed, soda ash and other substances can be added appropriately, but the alkalinity of the reduction bath should not be too strong, otherwise the dye reduction rate will slow down.

2) The dye leuco in the dyeing solution is absorbed by the fiber. The leuco of the sulfur dye exists in the anion state in the dyeing solution. It has directness to the cellulose fiber and can be adsorbed on the surface of the fiber and diffused into the interior of the fiber. Sulfur dye leuco has low directness to cellulose fiber, generally adopts small bath ratio, and adds appropriate electrolyte at the same time, can increase dyeing rate at higher temperature, and improve level dyeing and penetration.

3) Oxidation treatment After the sulfur dye leuco is dyed on the fiber, it must be oxidized to show the desired color. Oxidation is an important step after dyeing with sulfur dyes. After dyeing, easily oxidized sulfur dyes can be oxidized by air after washing and ventilating, that is, the air oxidation method is used; for some sulfur dyes that are not easily oxidized, oxidizing agents are used to promote oxidation.

4) Post-processing Post-processing includes cleaning, oiling, anti-brittleness and color fixation, etc. Sulfur dyes must be fully washed after dyeing to reduce the residual sulfur on the fabric and prevent the fabric from being brittle, because the sulfur in the dye and the sulfur in the vulcanized alkali are easily oxidized in the air to form sulfuric acid, which will cause acid hydrolysis to the cellulose fiber and cause damage. Reduce the strength and make the fiber brittle. Therefore, it can be treated with anti-brittle agents, such as: urea, trisodium phosphate, bone glue, sodium acetate, etc. In order to improve the sunlight and soaping fastness of sulfur dyes, it can be fixed after dyeing. There are two methods of color fixing treatment: metal salt treatment (such as potassium dichromate, copper sulfate, copper acetate and mixtures of these salts) and cationic color fixing agent treatment (such as color fixing agent Y). In production, it is better to use color-fixing agent M, which is compounded by cationic color-fixing agent and copper salt, which can reduce chromium pollution.

Problems:

The production process of sulfur dyes is short, the price is low, and the fastness is good, but because it still has many shortcomings and problems in actual production and application, it still cannot be widely used in various fabrics.

Sodium sulfide is used in the application of sulfur dyes, and it is excessive. Part of the sodium sulfide is used for the reduction of dyes, but the excess part will produce sulfur-containing wastewater. The dyeing wastewater has a high sulfur content. The waste water cannot be fully treated, and the discharge water quality is difficult to meet the requirements. If it is discharged directly, hydrogen sulfide will be released, which will cause harm to organisms, and will also corrode the sewage system and release odor, which will damage people’s health (the dye itself is harmful to the human body. There is no harm to the health of the user and it is considered a non-toxic dye).

In order to solve the wastewater problem, the factory needs to invest a lot of money, which not only greatly increases the production cost, but also easily produces toxic hydrogen sulfide gas during the dyeing process. When it reaches a certain level in the air, it can cause dizziness, heart palpitations, nausea, etc. Certainly dangerous.

This is one of the important reasons for the gradual decline of sulfur dyes. Because sulfur dyes are insoluble in water, dyed fabrics are not resistant to rubbing and are not resistant to chlorine bleaching. And because a large amount of sulfide used for dyeing remains in the dyed object, the finished product is brittle due to the oxidation of air to produce sulfate radicals during storage. The dyed matter of the most used black sulfur dye is brittle during storage. Due to the poor workability of sulfur dye dissolution, liquid products have been developed in recent years, but they are only pre-reduced sulfur dyes that have been dissolved. Ordinary sulfur dyes are dangerous substances with strong alkalinity and odor, poor storage stability, easy to stain and difficult to wash off due to their affinity to objects. Sulfur dyes need to be reduced and dissolved before dyeing fibers, and the post-treatment process steps are cumbersome, and the entire dyeing process is relatively complicated. Dyeing fabrics is usually limited to cellulose fibers like cotton. The shade of sulfur dyes is relatively dim, black is its most important color spectrum, followed by blue, olive and brown, it is difficult to meet the needs of people in modern society for rich and colorful colors.

Solution:

As some countries ban certain carcinogenic azo dyes. The development of new sulfur dyes, especially water-soluble sulfur dyes, will also have broad prospects for protein fibers.

At present, 90% of the world’s sulfur dyes are still using sodium sulfide, and it is excessive. Part of the sodium sulfide is used for the reduction of dyes, but the excess will produce sulfur-containing wastewater. Discharging it directly will pollute the environment. Further development of sulfur dyes will replace the currently used reducing agent sodium sulfide. In this regard, the cost increase must be similar to the current cost of treating sulfur-containing wastewater by chlorination. As people’s requirements for the environment are getting higher and higher, environmental protection is becoming more and more important. It is necessary to carry out ecological selection of reducing agents and oxidizing agents for sulfur dyeing. At the same time, the use of sulfur dyes that do not contain sulfur or contain very little sulfur can make the application of sulfur dyes an environmentally friendly process. Therefore, it is of great significance to increase the dyeing rate and dye utilization rate of sulfur dyes, thereby reducing the residual amount of dyes in wastewater.

The meaning of dyeing rate includes two aspects:

1) The adsorption rate of the dye in the dye liquor by the surface of the fiber;

2) The diffusion rate of the dye in the dye liquor from the surface of the fiber to the interior of the fiber.

Sulfur dyes are insoluble in water and must be fully reduced and dissolved with a reducing agent before dyeing. For a small number of sulfur dyes with large particles and poor solubility, they must be stirred or even boiled after adding sodium sulfide to help the dyes fully dissolve. On the other hand, the cellulose fiber is modified to increase the number of groups combined with the dye, thereby improving the utilization rate of the dye.

l Precautions for sodium sulfide

Dangerous

a) Health hazard: This product can decompose hydrogen sulfide in the gastrointestinal tract, and can cause hydrogen sulfide poisoning after oral administration. Corrosive to skin and eyes.

b) Environmental Hazard: Hazardous to the environment.

c) Explosion hazard: This product is flammable, highly corrosive and irritating, and can cause burns to the human body.

First-aid

a) Skin contact: Immediately take off contaminated clothing and rinse with plenty of running water for at least 15 minutes. Seek medical attention.

b) Eye contact: Immediately lift the eyelids and rinse thoroughly with plenty of running water or normal saline for at least 15 minutes. Seek medical attention.

c) Inhalation: Get away from the scene quickly to fresh air. Keep airway open. If breathing is difficult, give oxygen. If not breathing, give artificial respiration immediately. Seek medical attention.

d) Ingestion: Rinse mouth with water, give milk or egg whites. Seek medical attention.

Fire-fighting measures

a) Hazardous characteristics: the anhydrous substance is spontaneously combustible, and its dust is easy to spontaneously combust in the air. It decomposes in case of acid and emits highly toxic and flammable gas. Powder and air can form explosive mixtures. Its aqueous solution is corrosive and strongly irritating. It begins to evaporate at 100°C, and the vapor can corrode glass.

b) Hazardous combustion products: hydrogen sulfide, sulfur oxides.

c) Fire extinguishing method: Use water, spray water, sand to extinguish fire.

Spill handling

a) Emergency treatment: isolate the leaked contaminated area and restrict access. It is recommended that emergency personnel wear dust masks (full face masks) and anti-acid and alkali work clothes. Enter the site from upwind.

b) Small amount of leakage: avoid raising dust, collect with a clean shovel in a dry, clean container with a cover. It can also be washed with a large amount of water, and the washed water is diluted and put into the waste water system.

c) Large amount of spillage: collect and recycle or transport to waste disposal site for disposal.

disposal storage

a) Handling Precautions: Closed operation. Operators must undergo special training and strictly abide by the operating procedures. It is recommended that operators wear self-priming filter dust masks, chemical safety protective glasses, rubber acid and alkali resistant clothing, and rubber acid and alkali resistant gloves. Keep away from fire and heat sources, and smoking is strictly prohibited in the workplace. Use explosion-proof ventilation systems and equipment. Avoid generating dust. Avoid contact with oxidizing agents and acids. When handling, load and unload lightly to prevent damage to packaging and containers. Equipped with corresponding types and quantities of fire-fighting equipment and leakage emergency treatment equipment. Empty containers may be harmful residues.

b) Precautions for storage: Store in a cool, ventilated warehouse. Keep away from fire and heat sources. The humidity in the library is preferably not greater than 85%. The package is sealed. It should be stored separately from oxidants and acids, and should not be stored together. It should not be stored for a long time to avoid deterioration. Equipped with the appropriate variety and quantity of fire equipment. Storage areas should be equipped with suitable materials to contain spills.

l Precautions for packaging and transportation

1. Packing method: Put it into 0.5 mm thick steel drums and seal tightly, and the net weight of each drum should not exceed 100 kg; screw-top glass bottles, iron cap crimped glass bottles, plastic bottles or ordinary wooden boxes outside metal drums (cans); Screw-top glass bottle, plastic bottle or tin-plated thin steel drum (can) covered with floor grate box, fiberboard box or plywood box; tin-plated thin steel drum (can), metal drum (can), plastic bottle or metal hose Outer corrugated box.

2. Transportation precautions: When transported by rail, steel drums can be transported by open car. When transporting by rail, it should be assembled in strict accordance with the dangerous goods assembly table in the “Rules for the Transport of Dangerous Goods” issued by the Ministry of Railways. The packaging should be complete and the loading should be secure at the time of shipment. During transportation, it is necessary to ensure that the container does not leak, collapse, fall or be damaged. It is strictly forbidden to mix and transport with oxidants, acids, food chemicals, etc. When transporting, the transport vehicle should be equipped with corresponding types and quantities of fire-fighting equipment and leakage emergency treatment equipment.

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Post time: Mar-21-2023

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