Carbon Disulfide

Sulphide is a sulphur inorganic anion with the chemical formula S^-2, as well as a compound having one or more S^-2 ions. Sulphide salt solutions are corrosive. Large families of inorganic and organic substances, such as lead sulphide and dimethyl sulphide, are classified as sulphides. The conjugate acids of sulphide are hydrogen sulphide (H₂S) and bisulfide (SH).

Carbon disulfide was first prepared by a German chemist named Wilhelm August Lampadius in 1796. When pyrite was heated with moist charcoal carbon disulfide was formed, which he first called “Liquid Sulphur”. Then the composition was later found out by several other chemists.

What is Carbon Disulfide?

Carbon disulfide is a neurotoxic and colourless organic compound that is volatile in nature. Small amounts of carbon disulfide are released into the atmosphere during volcanic eruptions and marshes. It can also be manufactured by combining carbon and sulfur at high temperatures. The reaction would be:

C + 2S →CS₂

Formula of Carbon Disulphide

CS₂ is the formula for carbon disulfide. It can also be called Dithio Methane, Carbon bisulfide, Carbon sulphide, Sulfo Carbonic anhydride and Dithiocarbamic anhydride. This compound is frequently used in the field of organic chemistry and industries.

For the production of rayon fibre, about 13% of carbon disulfide is consumed in India. Carbon disulfide is used as a solvent for the production of selenium, bromine, iodine, rubber, fats, resins, and phosphorus. It is also used in the purification process of single tubed carbon nanotubes.

More concepts of carbon disulfide formula are discussed in this article.

Properties of Carbon Disulfide

Physical Properties:

• The chemical formula for carbon disulfide is CS₂ where the molecular weight is said to be 76.14 g mol^-1.

• Pure and impure carbon disulfide occurs in the form of a colourless liquid and yellowish respectively. It is not easily soluble in water.

• Carbon disulfide is highly flammable and can evaporate rapidly at room temperature.

• Pure carbon disulfide odour is similar to the sweet and pleasant smell of chloroform. Whereas the commercial grades of CS₂ give a foul odour that smells like rotten eggs.

• Carbon disulfide structure is linear in nature.

Chemical Properties:

• The vapour pressure of carbon disulfide at 25^oC is 352.6 mm Hg.

• The boiling point of CS₂ is 46.24 celsius.

• The melting point of CS₂ is -111.61^oC.

• The density of CS₂ is 1.539 g cm^-3.

• It can be soluble in alcohol, benzene, ether, and oil.

Concepts of Carbon Disulfide Formula

Carbon disulfide can react with other elements and it is highly flammable:

• Since it is flammable it can undergo the process of combustion and form sulphur dioxide.

CS₂ + 3O₂ CO₂ + 2SO₂

• Reaction with nucleophiles: CS₂ is a weaker electrophile when compared to isoelectronic carbon dioxide. When nucleophiles are reacted with CO₂ the reactions are said to be highly reversible and the produced products can be isolated with strong nucleophiles. Where reactions with CS₂ are more favoured where the products are formed with less reactive nucleophiles.

Reaction with amines produces dithiocarbamates.

2R₂NH + CS₂ → [R₂NH₂⁺][R₂NCS₂^-]

Reaction with alkoxides forms xanthates.

RONa + CS₂ → [Na⁺][ROCS₂^-]

Reaction with sodium sulphide produces trithiocarbonate.

Na₂S + CS₂ → [Na⁺]2[CS3^2-]

• Reduction: When carbon disulfide undergoes a reduction process with sodium it produces sodium 1,3-dithiole-2-thione-4,5-dithiolate and sodium trithiocarbonate.

4Na + 4CS₂ → Na₂C₃S₅ + Na₂CS₃

• Chlorination: The chlorination of CS₂ provides carbon tetrachloride.

CS₂ + 3Cl₂ → CCl₄ + S₂Cl₂

Carbon Disulfide Uses

Due to the properties of carbon disulfide, it can be found used in a few applications.

• The industrial uses are the manufacture of viscose rayon and cellophane film.

• It is used as an intermediate in the chemical synthesis of carbon tetrachloride.

• It is used in the production of organosulfur compounds like xanthates and dithiocarbamates. These are widely used in extractive metallurgy and rubber chemistry.

• Preparing soil disinfectants.

• Used as a solvent for fats, resins, sulphur, bromine, iodine, phosphorus, etc.

• In the manufacture of electronic vacuum tubes.

Health Hazards

Acute Effects

• Acute inhalation exposure of humans caused changes in breathing and some chest pains during an accidental release of carbon disulfide.

• Nausea, vomiting, dizziness, fatigue, headache, mood changes, lethargy, blurred vision, delirium, and convulsions have also been reported in humans acutely exposed by inhalation.

• convulsions have also been reported in humans acutely exposed by inhalation.

• Brain chemistry changes and sensory and motor nerve conduction alterations were observed in rats acutely exposed to carbon disulfide by inhalation.

• Animal studies show transitory effects associated with the target organ toxicity (central nervous system (CNS), blood, liver, eyes) seen from chronic exposure.

• Tests involving acute exposure of rats, mice, and rabbits have shown carbon disulfide to have low acute toxicity from inhalation and moderate acute toxicity by ingestion.

Reproductive/Developmental Effects

• Reproductive effects, such as decreased sperm count and decreased libido in men and menstrual disturbances in women, have been reported from occupational settings involving inhalation exposure to carbon disulfide.

• Developmental effects, including skeletal and visceral malformations, embryotoxicity, and functional and behavioural disturbances, have been observed in several animal studies across a wide exposure range.

• Pharmacokinetic studies indicate that carbon disulfide and its metabolites cross the placenta and localise in the target organs of the foetus (brain, blood, liver, and eyes).

Cancer Risk

• In a study of workers exposed by inhalation to carbon disulfide and other solvents, an increased incidence of lymphatic leukaemia was reported. However, there were many confounding factors in this study, making it difficult to interpret the results.

• EPA has not classified carbon disulfide for human carcinogenicity.

Conclusion

In this article, we learnt about liquid sulphur. It has both advantages and disadvantages. Where the advantages include its applications in several industries. Whereas its disadvantages include health hazards, it’s few chemical properties that are dangerous to the living organisms.