Sulfur: Obtaining, Properties, Uses, Features And Characteristics

Origin of the word Sulfur

Etymologically it comes from the Latin sulphurium , this in turn from the Sanskrit ?ulb?ri , a term that means " copper loses its value when joining sulfur." It was also called "flammable stone".

Sulfur history

Sulfur has been known since ancient times. In the Greek and Roman cultures medicinal properties were attributed to him and it was used in the whitening of fabrics; the Egyptians used it for the purification of the temples.

It played a leading role in the doctrines of the ancient alchemists, who considered this element as the missing component in the philosopher's stone to be able to make artificial gold .

Sulfur has been known since time immemorial, but as an element it was discovered by Henning Brand. An amateur merchant and alchemist from Hamburg (who also discovered phosphorus (P)). However, it was the French chemist Antoine Lavoisier who through a series of experiments conducted in 1777 discovered that sulfur is an element rather than a compound and was the first to classify it as a chemical element.

Where is sulfur found?

Free sulfur is found in volcanic deposits, hot springs , and also in underground deposits, mainly in the USA (Texas, Louisiana), Russia, Japan , Canada, France , Mexico , Poland and Sicily.

In the combined state it appears in the form of sulfides (pyrite and galena) and sulfates (gypsum) , in numerous minerals. It is also found in a wide variety of organic compounds such as animal proteins and some vegetables .

How is sulfur obtained?

Obtaining sulfur is carried out mainly through the Frash Process , a method to extract the element from the depths of the earth, melting the sulfur contained in underground deposits (it is a system similar to that of oil exploration).

Sulfur is also obtained from the separation of natural gas that contains hydrogen sulfide (H ₂ S), through the oxidation process. It is also extracted from oil , from the smelting of rocks that contain it, and from manual collection in deposits of pure sulfur combined with volcanic ash.

Sulfur characteristics

• As a non-metal , it is characterized by having no shine or luster.
• It does not reflect light and, in its natural state, it comes in a lemon yellow color.
• Its consistency is solid but soft and brittle.
• It is a poor conductor of heat and insulator of electricity .
• Its melting point is relatively low.
• It has four natural isotopes: ³² S (95.02%), ³³ S (0.75%), ³⁴ S (4.21%) and ³⁶ S (0.02%); twenty unstable with a half-life that ranges from 21 milliseconds, in addition to ³⁵ S (whose half-life is 87.32 days).

Structural forms of sulfur

• Solid sulfur is made up of a molecular structure of eight- atom misshapen rings and takes one of two crystalline forms: the orthorhombic octahedron (S?) and the monoclinic prism (S?). The arrangement of the molecules determines the forms listed, whose transition temperature from one to another is 96 ° C. At room temperature the transition of the form is slower.
• By raising the temperature , it turns into a transparent yellow and fluid liquid , which exhibits changes in its properties and structure. The color turns brown and thick and becomes clear again when it reaches the boiling point, turning into a red and viscous liquid. These changes in shape occur when the sulfur rings separate and break as a result of combustion. Cooling the viscous liquid produces a gummy mass called plastic sulfur. Once it cools, it crystallizes, adopting the rhombic structure.
• In the gas phase at 780 ° C it takes on a balanced form of mixing with diatomic molecules. Above 1800 ° C the molecular separation is complete and sulfur atoms are found.

Atomic Properties of Sulfur

• Average radius: 100 pm
• Electronegativity: 2.58 (Pauling scale)
• Atomic Radius (calc): 88 pm (Bohr Radius)
• Covalent Radius: 102 pm
• Van der Waals radius: 180 pm
• Oxidation state (s): ± 2, 4.6 (strong acid)
• 1st ionization energy: 999.6 kJ / mol
• 2nd ionization energy: 2252 kJ / mol
• 3rd Ionization energy: 3357 kJ / mol
• 4th Ionization energy: 4556 kJ / mol
• 5th Ionization energy: 7004.3 kJ / mol
• 6th Ionization energy: 8495.8 kJ / mol

Sulfur physical properties

• Ordinary state: Solid
• Density: 1960 kg / m ³
• Melting point: 388.36 K (115 ° C)
• Boiling point: 717.87 K (445 ° C)
• Enthalpy of vaporization: 5 kJ / mol
• Enthalpy of fusion: 1.7175 kJ / mol
• Vapor pressure: 2.65 × 10 ^-20 Pa at 388 K
• Critical point: 1314 K (1041 ° C) (20.7 MPa)

Uses of sulfur

Nutritional properties of sulfur

• Vegetables . Broccoli, cabbages, turnip; garlic and onion; cucumber, pepper, aubergines; soybeans, lentils, beans; mango, grapefruit, orange, plum, pear, banana, apple; sunflower seeds, oats.
• Carnes . Fish and shellfish

Sulfur Cycle

• From the soil , air or water to the vegetables by absorption.
• From vegetables to animals by ingestion.
• It reaches the atmosphere in the form of gases emitted by decomposition of organic matter (hydrogen sulfide - H ₂ S and sulfur dioxide - SO ₂ ) or volcanoes .
• It returns to the soil and water by depositions, rain or decomposition of living beings and by penetration of the atmosphere by gases.
• Acid rain : the SO ₂ accumulated in the atmosphere can combine with another oxygen atom to form sulfur trioxide (SO ₃ ) which, in contact with atmospheric humidity, becomes sulfuric acid (H ₂ SO ₄ ), which is harmful to life . It precipitates to the surface in the form of “acid rain”. To combat acid rain, it is necessary to reduce polluting gas emissions, save energy and reduce the consumption of fossil fuels that contain sulfur.

World production and sulfur reserves

Negative effects of sulfur on health

• Neurological and cardiac damage
• Behavioral changes
• Impaired circulation and respiration
• Impairment of the senses: sight and hearing
• Impairment of the reproductive and immune system and hormonal metabolism
• Stomach and gastrointestinal disorders
• Damage to liver and kidney functions
• Skin irritation on contact
• Irritation of lungs and mucous membranes by inhalation

Sulfur toxicity

Abubakr Conner

Abubakr Conner brings a diverse skill set to our team, and covers everything from analysis to the culture of food and drink. He Believes: "Education is the most powerful weapon that exists to change the world." .