SULPHUR

SULPHUR = BRIMSTONE

CAS number: 7704-34-9
EC number: 231-722-6
Formula: S

Sulphur (or sulfur in British English) is a chemical element with the symbol S and atomic number 16. 
Sulphur is abundant, multivalent and nonmetallic. 
Elemental Sulphur is a bright yellow, crystalline solid at room temperature.
Sulphur is the tenth most abundant element by mass in the universe and the fifth most on Earth. 

Though sometimes found in pure, native form, Sulphur on Earth usually occurs as sulfide and sulfate minerals. 
Being abundant in native form, Sulphur was known in ancient times, being mentioned for Sulphur's uses in ancient India, ancient Greece, China, and ancient Egypt. 
Historically and in literature Sulphur is also called brimstone, which means "burning stone".
Today, almost all elemental Sulphur is produced as a byproduct of removing Sulphur-containing contaminants from natural gas and petroleum.

The greatest commercial use of the element is the production of sulfuric acid for sulfate and phosphate fertilizers, and other chemical processes. 
Many Sulphur compounds are odoriferous, and the smells of odorized natural gas, skunk scent, grapefruit, and garlic are due to organosulfur compounds. 
Hydrogen sulfide gives the characteristic odor to rotting eggs and other biological processes.
Sulphur is an essential element for all life, but almost always in the form of organosulphur compounds or metal sulfides. 

Amino acids (two proteinogenic: cysteine and methionine, and many other non-coded: cystine, taurine, etc.) and two vitamins (biotin and thiamine) are organosulphur compounds crucial for life. 
Many cofactors also contain sulphur, including glutathione, and iron–Sulphur  proteins. 
Disulfides, S–S bonds, confer mechanical strength and insolubility of the (among others) protein keratin, found in outer skin, hair, and feathers. 

Sulphur is one of the core chemical elements needed for biochemical functioning and is an elemental macronutrient for all living organisms.
All living things need sulphur. 
Sulphur is especially important for humans because Sulphur is part of the amino acid methionine, which is an absolute dietary requirement for us. 
The amino acid cysteine also contains sulphur. 

The average person takes in around 900 mg of sulphur per day, mainly in the form of protein.
Elemental sulphur is not toxic, but many simple sulphur derivates are, such as sulphur dioxide (SO2) and hydrogen sulfide.
Sulphur can be found commonly in nature as sulphides. 
Sulphur can be found in the air in many different forms. 

 
Sulphur is applied in industries widely and emitted to air, due to the limited possibilities of destruction of the Sulphur bonds that are applied.
Sulphur is a multivalent non-metal, abundant, tasteless and and odorless. 
In Sulphur's native form sulphur is a yellow crystalline solid. 

In nature Sulphur occurs as the pure element or as sulfide and sulfate minerals. 
Although sulphur is infamous for Sulphur's smell, frequently compare to rotten eggs, that odor is actually characteristic of hydrogen sulphide (H2S).
The crystallography of sulphur is complex. 
Depending on the specific conditions, sulphur allotropes form several distinct crystal structures.

Sulphur (S), also spelled sulphur, nonmetallic chemical element belonging to the oxygen group (Group 16 [VIa] of the periodic table), one of the most reactive of the elements. 
Pure Sulphur is a tasteless, odourless, brittle solid that is pale yellow in colour, a poor conductor of electricity, and insoluble in water. 
Sulphur reacts with all metals except gold and platinum, forming sulfides.
Sulphur also forms compounds with several nonmetallic elements. 

Millions of tons of Sulphur are produced each year, mostly for the manufacture of sulfuric acid, which is widely used in industry.
In cosmic abundance, Sulphur ranks ninth among the elements, accounting for only one atom of every 20,000–30,000. 
Sulphur occurs in the uncombined state as well as in combination with other elements in rocks and minerals that are widely distributed, although Sulphur is classified among the minor constituents of Earth’s crust, in which Sulphur's proportion is estimated to be between 0.03 and 0.06 percent. 

On the basis of the finding that certain meteorites contain about 12 percent sulphur, it has been suggested that deeper layers of Earth contain a much larger proportion. 
Seawater contains about 0.09 percent Sulphur in the form of sulfate. 
In underground deposits of very pure Sulphur that are present in domelike geologic structures, the Sulphur is believed to have been formed by the action of bacteria upon the mineral anhydrite, in which Sulphur is combined with oxygen and calcium. 

Deposits of Sulphur in volcanic regions probably originated from gaseous hydrogen sulfide generated below the surface of Earth and transformed into Sulphur by reaction with the oxygen in the air.
Insoluble Sulphur is non-blooming rubber vulcanizing agent for tires, produced by the CS2 continuous one-step method, with high thermal stability and good dispersibility.
Sulphur is the fourth exception, and in this case the temperature at which the reference state changes from liquid Sulphur to Sulphur vapor is the problem.

Sulphur naturally consists of four stable isotopes 32S (95%), 33S (0.76%), 34S (4.22%), and 36S (0.014%). 
The atomic number of Sulphur is 16 and its atomic weight is 32.066 g mol−1. 
Sulphur has the most allotropes of any element, the most stable of these being orthorhombic S8. 
Commercial Sulphur melts at ∼119°C and boils at 444.6°C. 

Sulphur's density varies from 1.808 g cm−3 at 115°C to 1.599–1.614 g cm−3 at the boiling point. 
Sulphur is an odorless, tasteless, and brittle solid. 
Sulphur is a poor conductor of heat and electricity. 
Pure solid Sulphur is pale yellow. 
Sulphur is stable to air and water.

Almost all the elements, apart from gold, platinum, and the inert gases, combine with sulphur.
Sulphur is found both in its native form and in metal sulfide ores. 
Sulphur occurs in its native form in the vicinity of volcanoes and hot springs. 
Sulphur is the 10th most abundant element, and it is found in meteorites, in the ocean, in the earth's crust, in the atmosphere, and in practically all plant and animal life. 

The abundance of Sulphur in the earth's crust is 0.03–0.1%. Sediments (Sulphur concentration ∼4250 μg g−1) have accumulated a large proportion (43%) of the total Sulphur of the earth's crust. 
Metamorphic and magma rocks, which are the other typical materials of the crust, contain less Sulphur (concentration ∼600 μg g−1). 
Pyrite is the most common mineral form of Sulphur in sediments. 
The storage of Sulphur in sediments and ocean crusts (the Sulphur concentration of seawater is ∼900 μg g−1) is balanced by the degassing of volcanic rocks. 

High-purity Sulphur is commercially available in purities of 99.999%+.
Sulphur are usually yellow to yellowish-brown blocky dipyramids, with thick tabular and disphenoidal crystals less common. 
Also found more typically as powdery yellow coatings. 
Most native sulphur is found in sedimentary rocks, where large deposits are formed by reduction of sulfates, often biogenically. 

Sulphur is a common deposition product from volcanic gases associated with realgar, cinnabar and other minerals. 
Sulphur is also found in some vein deposits and as an alteration product of sulphide minerals.
Sulphur (S) is an element that can never be overlooked. 
In the periodic table, Sulphur is found in group 16. 

Sulphur is non-metal and is obtained as a byproduct after the production of natural gas.  
In colour, Sulphur is bright yellow, and it has an extremely bad odour (like rotten eggs). 
Outside the apparent physical characters of sulphur, humans have been consuming this element since a thousand years. 
Sulphur is frequently found near hot springs and volcanoes. 

Sulphur mentions can be found even in the Bible, where Sulphur is entitled brimstone.
Sulphur is an element that is simple to find on the ground and even simpler to discover in the periodic table. 
Sulphur is just below oxygen (O) at the sixteenth position. 
Sulphur, when found naturally, is a yellowish colour and is frequently found as crystal. 

Sulphur is non-reactive at normal temperatures.
Sulphur plays a key role in the body and is necessary for the synthesis of some key proteins. 
Sulphur, for example, is needed for the glutathione synthesis, which acts as a potent antioxidant to protect your cells from damage.
Sulphur is an ingredient approved by the FDA for use in dandruff products of over-the-counter nature. 

Sulphur often comes in combination with salicylic acid. 
Sulphur makes up almost 3 per cent of the Earth’s surface.
Sulphur is also thought to have been a part of the ‘Greek Fire,’ a flamethrower-like device used by the Byzantine Empire.
The Sulphur obtained from molten Sulphur is called monoclinic Sulphur while rhombic Sulphur is called Sulphur obtained from crystallizing a solution. 

Both forms are composed of rings S8. 
The distinction between the forms is how they organize the rings inside a crystal.
There is no smell of pure Sulphur but many of Sulphur's compounds stink! 
Sulphur compounds called mercaptans, for example, give skunks their gruesome smell. 

Rotten eggs (and most stink bombs) get their distinctive hydrogen sulfide, H2S, flavouring.
Sulphur occurs in many allotropes, both crystalline and amorphous. 
The most common form is bright, orthorhombic alpha-sulphur, containing puckered S8 rings.
Sulphur occurs in many allotropes, both crystalline and amorphous. 

Hydrogen sulfide ( H2S) is the best-known sulphur compound. 
Sulphur helps to dry out the skin’s surface and help absorb excess oil (sebum) which can lead and acne breakouts. 
To help unblock your pores Sulphur also dries out dead skin cells. 
Sulphur is recovered from natural gas , coal, crude oil, and other sources such as flue dust and gasses from metal sulfide ores refining. 

Elemental Sulphur is obtained in various forms including Sulphur flowers, fine crystalline powder and roll sulphur.
Sulphur , in the human body, is the third most abundant chemical. 
The factor is also present in a variety of foods, including garlic , onions, eggs and foods high in proteins. 
Sulphur is necessary for the synthesis of the essential cysteine and methionine amino acids.

Sulphur (S) is an important nutrient for grassland production, and is closely associated with nitrogen uptake and efficiency. 
If there is a sulphur deficiency present sulphur deficiency will decrease the nitrogen use efficiency and reduce yield. 
Sulphur is an essential element for life. 
Sulphur is found in amino acids (cysteine and methionine) and proteins. 

Sulphur compounds are why onions make you cry, why asparagus gives urine a weird odor, why garlic has a distinctive aroma, and why rotten eggs smell so horrible.
Although many Sulphur compounds have a strong smell, the pure element is odorless. 
Sulphur compounds also affect your sense of smell. 
For example, hydrogen sulfide (H2S, the culprit behind the rotten egg odor) actually deadens the sense of smell, so the odor is very strong at first and then vanishes. 

Elemental Sulphur is not harmful.
Mankind has known about Sulphur since ancient times. 
The element, also known as brimstone, primarily comes from volcanoes. 
While most chemical elements occur only in compounds, Sulphur is one of relatively few elements that occur in pure form.

At room temperature and pressure, Sulphur is a yellow solid. 
Sulphur is usually seen as a powder, but it forms crystals, too. 
One interesting feature of the crystals is that Sulphur spontaneously change shape according to temperature. 
To observe the transition, melt sulphur, allow Sulphur to cool until Sulphur crystallizes, and observe the crystal shape over time.

While Sulphur is a nonmetal, like metals it won't readily dissolve in water or other solvents (although it will dissolve in carbon disulfide). 
Liquid Sulphur can appear blood-red. 
Volcanoes that spew molten Sulphur display another interesting feature of the element: Sulphur burns with a blue flame from the Sulphur dioxide that is produced. 
Volcanoes with Sulphur appear to run with blue lava.

The International Union of Pure and Applied Chemistry (IUPAC) adopted the Sulphur spelling in 1990, as did the Royal Society of Chemistry in 1992. 
Up to this point, the spelling was sulphur in Britain and in countries using the Roman languages. 
The original spelling was the Latin word sulphur, which was Hellenized to sulphur.
Sulphur has many uses. 

Sulphur is created as part of the alpha process in massive stars. 
Sulphur is the 10th most abundant element in the universe. 
Sulphur is found in meteorites and on Earth mainly near volcanoes and hot springs. 
The abundance of the element is higher in the core than in the Earth's crust. 

It's estimated there is enough Sulphur on Earth to make two bodies the size of the Moon. 
Common minerals that contain Sulphur include pyrite or fool's gold (iron sulfide), cinnabar (mercury sulfide), galena (lead sulfide), and gypsum (calcium sulfate).
An example are cave bacteria, which produce special stalactites called snottites that drip sulfuric acid. 
Natural dissolution of minerals by the acid carves out new caves.

Although people always knew about sulphur, Sulphur wasn't recognized until later as an element (except by alchemists, who also considered fire and earth elements). 
It was 1777 when Antoine Lavoisier provided convincing evidence that Sulphur was indeed Sulphur's own unique element, worthy of a place on the periodic table. 
The element has oxidation states ranging from -2 to +6, allowing Sulphur to form compounds with all the other elements except the noble gases.
Sulphur-containing compounds are essential elements for pigs. 

The sulphur content of whole grains (wheat, corn) is relatively low, usually close to 1.3g/kg. 
Sulphur content in feedstuffs based on cereals like corn gluten meal can be more than 10g/kg.
Dietary sulphur content is directly linked to sulphur amino acids, sulphate-containing ingredients (e.g. trace minerals) and by-products from the milling industry pre-treated with sulphuric acid to enhance starch extraction. 

A pale yellow chemical element that exists in various physical forms. 
A chemical element. 
Sulphur is a pale yellow substance that produces a strong unpleasant smell when Sulphur burns and is used in medicine and industry.
The spelling Sulphur has been adopted by the International Union of Pure and Applied Chemistry and by the Royal Society of Chemistry in the UK. 

However, sulphur still remains the usual spelling in British, Irish, South African and Indian English. Both spellings are used in Canadian, Australian and New Zealand English.
Sulphur is a yellow chemical which has a strong smell.
an allotropic nonmetallic element, occurring free in volcanic regions and in combined state in gypsum, pyrite, and galena. 

The stable yellow rhombic form converts on heating to monoclinic needles. 
Yellow with a greenish tinge; lemon color.
Sulphur is a by-product produced in various refineries processing high Sulphur crude crude. 
Sulphur is produced from the Sulphur rich fuel gas to reduce the emission level of Sulphur in the atmosphere along with flue gases from the furnaces. 

Sulphur (S) is the fourth macronutrient, but ranks as the third most limiting nutrient on the Prairies. 
Sulphur deficiency in western Canada was first identified in 1927 on Gray Wooded soils in Alberta. 
Canola is more sensitive than cereals to sulphur deficiency and frequently responds to fertilizer sulphur addition. 
Sulphur is an essential nutrient for a wide range of agricultural and horticultural crops and required in considerable amounts. 

Cereals, oilseed rape and multi-cut grass are especially demanding of sulphur. 
Soil sulphur is easily leached making shallow-rooting plants particularly vulnerable to deficiency. 
Availability varies with soil and area and it is possible for any soil to be deficient. Soils of pH less than 5 or more than 8 have particularly limited sulphur availability.
A yellow chemical element that has a strong smell. 

USES and APPLICATIONS of SULPHUR:
-The major derivative of sulphur is sulphuric acid (H2SO4), one of the most important elements used as an industrial raw material.
-Sulphur is also used in batteries, detergents, fungicides, manufacture of fertilizers, gun power, matches and fireworks. 
-Other applications are making corrosion-resistant concrete which has great strength and is forst resistant, for solvents and in a host of other products of the chemical and pharmaceutical industries.

-Sulphur burns with a blue flame and a strong smell and is used in medicine and industry.
-Sulphur (S) is an essential plant nutrient. 
Sulphur contributes to increase crop yield by providing direct nutritive value, as well as indirect nutritive value by enhancing soil productivity and improving use efficiency of other key nutrients (nitrogen and phosphorus).

-Sulphur is naturally present in the environment and was mined for many years, however most of today’s elemental sulphur is produced as a by-product from oil refining and gas processing plants.
-Sulphur is used in matches, insecticides, and fungicides.
-Some organisms are able to use Sulphur compounds as an energy source. 

-Sulfuric acid:
Elemental Sulphur is used mainly as a precursor to other chemicals. 
Approximately 85% (1989) is converted to sulfuric acid (H2SO4):
2 S + 3 O2 + 2 H2O → 2 H2SO4
In 2010, the United States produced more sulfuric acid than any other inorganic industrial chemical.
The principal use for the acid is the extraction of phosphate ores for the production of fertilizer manufacturing. 
Other applications of sulfuric acid include oil refining, wastewater processing, and mineral extraction.

-Other important Sulphur chemistry:
Sulphur reacts directly with methane to give carbon disulfide, which is used to manufacture cellophane and rayon.
One of the uses of elemental Sulphur is in vulcanization of rubber, where polysulfide chains crosslink organic polymers. 
Large quantities of sulfites are used to bleach paper and to preserve dried fruit. 

Many surfactants and detergents (e.g. sodium lauryl sulfate) are sulfate derivatives. 
Calcium sulfate, gypsum, (CaSO4·2H2O) is mined on the scale of 100 million tonnes each year for use in Portland cement and fertilizers.
When silver-based photography was widespread, sodium and ammonium thiosulfate were widely used as "fixing agents". 
Sulphur is a component of gunpowder ("black powder").

-Fertilizer:
Sulphur is increasingly used as a component of fertilizers. 
The most important form of Sulphur for fertilizer is the mineral calcium sulfate. 
Elemental Sulphur is hydrophobic (not soluble in water) and cannot be used directly by plants. 
Over time, soil bacteria can convert Sulphur to soluble derivatives, which can then be used by plants. 

Sulphur improves the efficiency of other essential plant nutrients, particularly nitrogen and phosphorus.
Biologically produced Sulphur particles are naturally hydrophilic due to a biopolymer coating and are easier to disperse over the land in a spray of diluted slurry, resulting in a faster uptake.
The botanical requirement for Sulphur equals or exceeds the requirement for phosphorus. 

Sulphur is an essential nutrient for plant growth, root nodule formation of legumes, and immunity and defense systems. 
Sulphur deficiency has become widespread in many countries in Europe.
Because atmospheric inputs of Sulphur continue to decrease, the deficit in the Sulphur input/output is likely to increase unless Sulphur fertilizers are used. 
Atmospheric inputs of Sulphur decrease because of actions taken to limit acid rains.

-Fungicide and pesticide:
Elemental Sulphur is one of the oldest fungicides and pesticides. 
"Dusting sulphur", elemental Sulphur in powdered form, is a common fungicide for grapes, strawberry, many vegetables and several other crops. 
Sulphur has a good efficacy against a wide range of powdery mildew diseases as well as black spot. 
In organic production, Sulphur is the most important fungicide. 

Sulphur is the only fungicide used in organically farmed apple production against the main disease apple scab under colder conditions. 
Biosulfur (biologically produced elemental Sulphur with hydrophilic characteristics) can also be used for these applications.
Standard-formulation dusting Sulphur is applied to crops with a Sulphur duster or from a dusting plane. 
Wettable Sulphur is the commercial name for dusting Sulphur formulated with additional ingredients to make it water miscible. 

Sulphur has similar applications and is used as a fungicide against mildew and other mold-related problems with plants and soil.
Elemental Sulphur powder is used as an "organic" (i.e., "green") insecticide (actually an acaricide) against ticks and mites. 
A common method of application is dusting the clothing or limbs with Sulphur powder.
A diluted solution of lime Sulphur (made by combining calcium hydroxide with elemental Sulphur in water) is used as a dip for pets to destroy ringworm (fungus), mange, and other dermatoses and parasites.

-Pharmaceuticals:
Sulphur (specifically octasulphur, S8) is used in pharmaceutical skin preparations for the treatment of acne and other conditions. 
Sulphur acts as a keratolytic agent and also kills bacteria, fungi, scabies mites, and other parasites.
Precipitated Sulphur and colloidal Sulphur are used, in form of lotions, creams, powders, soaps, and bath additives, for the treatment of acne vulgaris, acne rosacea, and seborrhoeic dermatitis.

Many drugs contain sulphur; early examples being antibacterial sulfonamides, known as sulfa drugs. 
Sulphur is a part of many bacterial defense molecules. 
Most β-lactam antibiotics, including the penicillins, cephalosporins and monobactams contain sulphur.

-Osteoarthritis is often treated with the use of Sulphur supplements.
-The principal industrial use of Sulphur in the manufacture of sulfuric acid ( H2SO4) is as a reactant. 
-Sulfuric acid is the number one bulk chemical in the developed world which is needed for automotive use in large quantities in lead-acid batteries.
-Some products contain Sulphur along with other ingredients used to fight acne, such as resorcinol.

-Sulphur is used as a fungicide and in black gunpowder for the vulcanisation of natural rubber. 
-Most Sulphur is used in sulfuric acid manufacturing, which is probably the most important chemical produced by Western civilisations.
-Sulphur is used for making car batteries, fertilizer, oil refining, water processing, and mineral extraction. 
-Other applications for sulphur-based chemicals include rubber vulcanization, bleaching paper, and product making such as cement, detergents, pesticides. 

-Sulphur is an important constituent in the major amino acids, cysteine and methionine and plays a critical role in protein synthesis and photosynthesis.
-Higher yielding crops require greater levels of Sulphur nutrition to maintain optimum yield, protein content and high nitrogen use efficiency.
-Sulphur is a component of gunpowder and is believed to have been used in the ancient flamethrower weapon called Greek Fire. 
-Sulphur is a key component of sulfuric acid, which is used in labs and in making other chemicals. 

-Sulphur is found in the antibiotic penicillin and is used for fumigation.
-Sulphur is a component of fertilizers and also pharmaceuticals.
-Industrial use,Professional use
-Manufacture of substance

-Distribution of substance
-Use as an intermediate
-Formulation & (re)packing of substances and mixtures
-Used as a fuel

-Sulphur is used for making medicines and explosives.
-Sulphur is the main source for sulphuric acid production, the world’s most used chemical. 
-In the fertilizer industry, sulphuric acid is mainly used to produce phosphates but also nitrogen, potassium and sulphate fertilizers. 
-In the metals industry Sulphur is used for mineral ore leaching to produce essentially Copper, Nickel and Zinc.
-Sulphur is used in the production of sulphuric acid, in the vulcanization of rubber, and in fungicides. 

PRODUCTION of SULPHUR:
Sulphur may be found by itself and historically was usually obtained in this form; pyrite has also been a source of sulphur.
In volcanic regions in Sicily, in ancient times, Sulphur was found on the surface of the Earth, and the "Sicilian process" was used: Sulphur deposits were piled and stacked in brick kilns built on sloping hillsides, with airspaces between them. 
Then, some Sulphur was pulverized, spread over the stacked ore and ignited, causing the free Sulphur to melt down the hills. 

Eventually the surface-borne deposits played out, and miners excavated veins that ultimately dotted the Sicilian landscape with labyrinthine mines. 
Mining was unmechanized and labor-intensive, with pickmen freeing the ore from the rock, and mine-boys or carusi carrying baskets of ore to the surface, often through a mile or more of tunnels. 
Once the ore was at the surface, Sulphur was reduced and extracted in smelting ovens. 

Elemental Sulphur was extracted from salt domes (in which it sometimes occurs in nearly pure form) until the late 20th century. 
Sulphur is now produced as a side product of other industrial processes such as in oil refining, in which Sulphur is undesired. 
As a mineral, native Sulphur under salt domes is thought to be a fossil mineral resource, produced by the action of anaerobic bacteria on sulfate deposits. 
Sulphur was removed from such salt-dome mines mainly by the Frasch process.

In this method, superheated water was pumped into a native Sulphur deposit to melt the sulphur, and then compressed air returned the 99.5% pure melted product to the surface. 
Throughout the 20th century this procedure produced elemental Sulphur that required no further purification. 
Due to a limited number of such Sulphur deposits and the high cost of working them, this process for mining Sulphur has not been employed in a major way anywhere in the world since 2002.

Today, Sulphur is produced from petroleum, natural gas, and related fossil resources, from which Sulphur is obtained mainly as hydrogen sulfide.
Organosulfur compounds, undesirable impurities in petroleum, may be upgraded by subjecting them to hydrodesulfurization, which cleaves the C–S bonds:
R-S-R + 2 H2 → 2 RH + H2S
The resulting hydrogen sulfide from this process, and also as Sulphur occurs in natural gas, is converted into elemental Sulphur by the Claus process. 

This process entails oxidation of some hydrogen sulfide to dioxide and then the comproportionation of the two:
3 O2 + 2 H2S → 2 SO2 + 2 H2O
SO2 + 2 H2S → 3 S + 2 H2O
Owing to the high Sulphur content of the Athabasca Oil Sands, stockpiles of elemental Sulphur from this process now exist throughout Alberta, Canada.
Another way of storing Sulphur is as a binder for concrete, the resulting product having many desirable properties (see Sulphur concrete).

Sulphur is still mined from surface deposits in poorer nations with volcanoes, such as Indonesia, and worker conditions have not improved much since Booker T. Washington's days.
The world production of Sulphur in 2011 amounted to 69 million tonnes (Mt), with more than 15 countries contributing more than 1 Mt each. Countries producing more than 5 Mt are China (9.6), US (8.8), Canada (7.1) and Russia (7.1).
Production has been slowly increasing from 1900 to 2010; the price was unstable in the 1980s and around 2010.

PHYSICAL PROPERTIES of SULPHUR:
Sulphur forms several polyatomic molecules. 
The best-known allotrope is octasulfur, cyclo-S8. 
The point group of cyclo-S8 is D4d and its dipole moment is 0 D.

Octasulfur is a soft, bright-yellow solid that is odorless, but impure samples have an odor similar to that of matches.
Sulphur melts at 115.21 °C (239.38 °F), boils at 444.6 °C (832.3 °F) and sublimates easily.
At 95.2 °C (203.4 °F), below Sulphur's melting temperature, cyclo-octasulfur changes from α-octasulfur to the β-polymorph.
The structure of the S8 ring is virtually unchanged by this phase change, which affects the intermolecular interactions. 
Between Sulphur's melting and boiling temperatures, octasulfur changes Sulphur's allotrope again, turning from β-octasulfur to γ-sulfur, again accompanied by a lower density but increased viscosity due to the formation of polymers.

At higher temperatures, the viscosity decreases as depolymerization occurs. 
Molten Sulphur assumes a dark red color above 200 °C (392 °F). 
The density of Sulphur is about 2 g/cm3, depending on the allotrope; all of the stable allotropes are excellent electrical insulators.
Sulphur is insoluble in water but soluble in carbon disulfide and, to a lesser extent, in other nonpolar organic solvents, such as benzene and toluene.

CHEMICAL PROPERTIES of SULPHUR:
Sulphur doesn't react with water.
At normal conditions, Sulphur reacts with especially active substances (fluorine).
For reactions with nonmetals having oxidative properties in relation to Sulphur (except fluorine) and with majority of metals as well, initial or constant inflow of heat is needed.

Sulphur burns in air with a blue flame with formation of Sulphur dioxide, which has a suffocating and irritating odor.
Sulphur reacts with concentrated strong acids and melted alkalies at constant heating.
The second, fourth and sixth ionization energies of Sulphur are 2252 kJ/mol–1, 4556 kJ/mol–1 and 8495.8 kJ/mol–1,respectively. 
A composition of products of Sulphur's reactions with oxidants (and Sulphur's oxidation state) depends on that whether releasing out of a reaction energy overcomes these thresholds. 

Applying catalysts and / or supply of outer energy may vary Sulphur 's oxidation state and a composition of reaction products. 
While reaction between Sulphur and oxygen at normal conditions gives Sulphur dioxide (oxidation state +4), formation of Sulphur trioxide (oxidation state +6) requires temperature 400 – 600°C and presence of a catalyst.
Sulphur forms nitrides, oxides, fluorides, chlorides, bromides (all of different composition), and Sulphur iodide (oxidation state +2).

In reactions with elements electronegativity of which less than Sulphur 's, Sulphur comes as an oxidant, and forms sulfides with oxidation state –2.
Sulphur reacts with nearly all other elements with the exception of the noble gases, even with the notoriously unreactive metal iridium (yielding iridium disulfide).
Some of those reactions need elevated temperatures.

ISOTOPES of SULPHUR:
When sulfide minerals are precipitated, isotopic equilibration among solids and liquid may cause small differences in the δ34S values of co-genetic minerals. 
The differences between minerals can be used to estimate the temperature of equilibration. 
The δ13C and δ34S of coexisting carbonate minerals and sulfides can be used to determine the pH and oxygen fugacity of the ore-bearing fluid during ore formation.
In most forest ecosystems, sulfate is derived mostly from the atmosphere; weathering of ore minerals and evaporites contribute some Sulphur.

Sulphur with a distinctive isotopic composition has been used to identify pollution sources, and enriched Sulphur has been added as a tracer in hydrologic studies. 
Differences in the natural abundances can be used in systems where there is sufficient variation in the 34S of ecosystem components. 
Rocky Mountain lakes thought to be dominated by atmospheric sources of sulfate have been found to have characteristic 34S values from lakes believed to be dominated by watershed sources of sulfate.

NATURAL OCCURENCE of SULPHUR:
32S is created inside massive stars, at a depth where the temperature exceeds 2.5×109 K, by the fusion of one nucleus of silicon plus one nucleus of helium.
As this nuclear reaction is part of the alpha process that produces elements in abundance, Sulphur is the 10th most common element in the universe.
Sulphur , usually as sulfide, is present in many types of meteorites. 
Ordinary chondrites contain on average 2.1% Sulphur, and carbonaceous chondrites may contain as much as 6.6%. 

Sulphur is normally present as troilite (FeS), but there are exceptions, with carbonaceous chondrites containing free Sulphur, sulfates and other Sulphur compounds.
The distinctive colors of Jupiter's volcanic moon Io are attributed to various forms of molten, solid, and gaseous Sulphur .
Sulphur is the fifth most common element by mass in the Earth. 
Elemental Sulphur can be found near hot springs and volcanic regions in many parts of the world, especially along the Pacific Ring of Fire; such volcanic deposits are currently mined in Indonesia, Chile, and Japan. 

These deposits are polycrystalline, with the largest documented single crystal measuring 22×16×11 cm.
Historically, Sicily was a major source of Sulphur in the Industrial Revolution.
Lakes of molten Sulphur up to ~200 m in diameter have been found on the sea floor, associated with submarine volcanoes, at depths where the boiling point of water is higher than the melting point of Sulphur.
Native Sulphur is synthesised by anaerobic bacteria acting on sulfate minerals such as gypsum in salt domes.

Significant deposits in salt domes occur along the coast of the Gulf of Mexico, and in evaporites in eastern Europe and western Asia. 
Native Sulphur may be produced by geological processes alone. 
Fossil-based Sulphur deposits from salt domes were once the basis for commercial production in the United States, Russia, Turkmenistan, and Ukraine.
Currently, commercial production is still carried out in the Osiek mine in Poland. 
Such sources are now of secondary commercial importance, and most are no longer worked.

Common naturally occurring Sulphur compounds include the sulfide minerals, such as pyrite (iron sulfide), cinnabar (mercury sulfide), galena (lead sulfide), sphalerite (zinc sulfide), and stibnite (antimony sulfide); and the sulfate minerals, such as gypsum (calcium sulfate), alunite (potassium aluminium sulfate), and barite (barium sulfate). 
On Earth, just as upon Jupiter's moon Io, elemental Sulphur occurs naturally in volcanic emissions, including emissions from hydrothermal vents.
The main industrial source of Sulphur is now petroleum and natural gas.

Life on Earth may have been possible because of sulphur. 
Conditions in the early seas were such that simple chemical reactions could have generate the range of amino acids that are the building blocks of life.
Sulphur occurs naturally near volcanoes. 
Native sulphur occurs naturally as massive deposits in Texas and Louisiana in the USA. 

Many sulphide minerals are known: pyrite and marcaiste are iron sulphide ; stibnite is antimony sulphide; galena is lead sulphide; cinnabar is mercury sulphide and sphalerite is zinc sulphide. 
Other, more important, sulphide ores are chalcopyrite, bornite, penlandite, millerite and molybdenite.
The chief source of sulphur for industry is the hydrogen sulphide of natural gas.

COMPOUNDS of SULPHUR:
Common oxidation states of Sulphur range from −2 to +6. 
Sulphur forms stable compounds with all elements except the noble gases.

-Allotropes:
Sulphur forms over 30 solid allotropes, more than any other element.
Besides S8, several other rings are known.
Removing one atom from the crown gives S7, which is more of a deep yellow than the S8. 
HPLC analysis of "elemental Sulphur" reveals an equilibrium mixture of mainly S8, but with S7 and small amounts of S6.

Larger rings have been prepared, including S12 and S18.
Amorphous or "plastic" Sulphur is produced by rapid cooling of molten sulphur—for example, by pouring it into cold water. 
X-ray crystallography studies show that the amorphous form may have a helical structure with eight atoms per turn. 
The long coiled polymeric molecules make the brownish substance elastic, and in bulk this form has the feel of crude rubber. 
This form is metastable at room temperature and gradually reverts to crystalline molecular allotrope, which is no longer elastic. 
This process happens within a matter of hours to days, but can be rapidly catalyzed.

-Polycations and polyanions:
Sulphur polycations, S82+, S42+ and S162+ are produced when Sulphur is reacted with mild oxidising agents in a strongly acidic solution.
The colored solutions produced by dissolving Sulphur in oleum were first reported as early as 1804 by C.F. Bucholz, but the cause of the color and the structure of the polycations involved was only determined in the late 1960s. S82+ is deep blue, S42+ is yellow and S162+ is red.
The radical anion S3− gives the blue color of the mineral lapis lazuli.

-Sulfides:
Treatment of Sulphur with hydrogen gives hydrogen sulfide. When dissolved in water, hydrogen sulfide is mildly acidic:
H2S ⇌ HS− + H+
Hydrogen sulfide gas and the hydrosulfide anion are extremely toxic to mammals, due to their inhibition of the oxygen-carrying capacity of hemoglobin and certain cytochromes in a manner analogous to cyanide and azide.
Reduction of elemental Sulphur gives polysulfides, which consist of chains of Sulphur atoms terminated with S− centers:
2 Na + S8 → Na2S8

This reaction highlights a distinctive property of Sulphur: Sulphur's ability to catenate (bind to itself by formation of chains). Protonation of these polysulfide anions produces the polysulfanes, H2Sx where x= 2, 3, and 4.
Ultimately, reduction of Sulphur produces sulfide salts:
16 Na + S8 → 8 Na2S
The interconversion of these species is exploited in the sodium–Sulphur battery.

-Oxides, oxoacids, and oxoanions:
The principal Sulphur oxides are obtained by burning Sulphur:
S + O2 → SO2 (Sulphur dioxide)
2 SO2 + O2 → 2 SO3 (Sulphur  trioxide)
Multiple Sulphur oxides are known; the Sulphur-rich oxides include Sulphur monoxide, disulphur monoxide, disulphur dioxides, and higher oxides containing peroxo groups.
Sulphur forms Sulphur oxoacids, some of which cannot be isolated and are only known through the salts. 
Sulphur dioxide and sulfites (SO2−3) are related to the unstable sulfurous acid (H2SO3). 

Sulphur trioxide and sulfates (SO2−4) are related to sulfuric acid (H2SO4). 
Sulfuric acid and SO3 combine to give oleum, a solution of pyrosulfuric acid (H2S2O7) in sulfuric acid.
Thiosulfate salts (S2O2−3), sometimes referred as "hyposulfites", used in photographic fixing (hypo) and as reducing agents, feature Sulphur in two oxidation states. 
Sodium dithionite (Na2S2O4), contains the more highly reducing dithionite anion (S2O2−4).

-Halides and oxyhalides:
Several Sulphur halides are important to modern industry. 
Sulphur hexafluoride is a dense gas used as an insulator gas in high voltage transformers; Sulphur is also a nonreactive and nontoxic propellant for pressurized containers. 
Sulphur tetrafluoride is a rarely-used organic reagent that is highly toxic.
Sulphur dichloride and disulfur dichloride are important industrial chemicals. 
Sulfuryl chloride and chlorosulfuric acid are derivatives of sulfuric acid; thionyl chloride (SOCl2) is a common reagent in organic synthesis.

-Pnictides:
An important S–N compound is the cage tetrasulphur tetranitride (S4N4). 
Heating this compound gives polymeric Sulphur nitride (SN
x), which has metallic properties even though it does not contain any metal atoms. 
Thiocyanates contain the SCN− group. 
Oxidation of thiocyanate gives thiocyanogen, (SCN)2 with the connectivity NCS−SCN. 
Phosphorus sulfides are numerous, the most important commercially being the cages P4S10 and P4S3.

-Metal sulfides:
The principal ores of copper, zinc, nickel, cobalt, molybdenum, and other metals are sulfides. 
These materials tend to be dark-colored semiconductors that are not readily attacked by water or even many acids. 
They are formed, both geochemically and in the laboratory, by the reaction of hydrogen sulfide with metal salts. 
The mineral galena (PbS) was the first demonstrated semiconductor and was used as a signal rectifier in the cat's whiskers of early crystal radios. 
The iron sulfide called pyrite, the so-called "fool's gold", has the formula FeS2.
Processing these ores, usually by roasting, is costly and environmentally hazardous. 
Sulphur corrodes many metals through tarnishing.

-Organic compounds:
Some of the main classes of sulphur-containing organic compounds include the following:
*Thiols or mercaptans (so called because they capture mercury as chelators) are the Sulphur analogs of alcohols; treatment of thiols with base gives thiolate ions.
*Thioethers are the Sulphur analogs of ethers. 
*Sulfonium ions have three groups attached to a cationic Sulphur center. 
Dimethylsulfoniopropionate (DMSP) is one such compound, important in the marine organic Sulphur cycle.
*Sulfoxides and sulfones are thioethers with one and two oxygen atoms attached to the Sulphur atom, respectively. 
The simplest sulfoxide, dimethyl sulfoxide, is a common solvent; a common sulfone is sulfolane.
*Sulfonic acids are used in many detergents.

Compounds with carbon–Sulphur multiple bonds are uncommon, an exception being carbon disulfide, a volatile colorless liquid that is structurally similar to carbon dioxide. 
Sulphur is used as a reagent to make the polymer rayon and many organoSulphur compounds. 
Unlike carbon monoxide, carbon monosulfide is stable only as an extremely dilute gas, found between solar systems.
Organosulphur compounds are responsible for some of the unpleasant odors of decaying organic matter. 
They are widely known as the odorant in domestic natural gas, garlic odor, and skunk spray. 
Not all organic Sulphur compounds smell unpleasant at all concentrations: the sulphur-containing monoterpenoid (grapefruit mercaptan) in small concentrations is the characteristic scent of grapefruit, but has a generic thiol odor at larger concentrations. 

Sulphur–sulphur bonds are a structural component used to stiffen rubber, similar to the disulfide bridges that rigidify proteins (see biological below). 
In the most common type of industrial "curing" or hardening and strengthening of natural rubber, elemental Sulphur is heated with the rubber to the point that chemical reactions form disulfide bridges between isoprene units of the polymer. 
This process, patented in 1843, made rubber a major industrial product, especially in automobile tires. 
Because of the heat and sulphur, the process was named vulcanization, after the Roman god of the forge and volcanism.

BIOLOGICAL ROLE of SULPHUR:
Sulphur is an essential component of all living cells. 
Sulphur is the eighth most abundant element in the human body by weight, about equal in abundance to potassium, and slightly greater than sodium and chlorine.
A 70 kg (150 lb) human body contains about 140 grams of sulphur.
Sulphur is vital for the production of insulin, keratin and collagen.

-Transferring Sulphur between inorganic and biomolecules:
In the 1880s, while studying Beggiatoa (a bacterium living in a Sulphur rich environment), Sergei Winogradsky found that it oxidized hydrogen sulfide (H2S) as an energy source, forming intracellular Sulphur droplets. 
Winogradsky referred to this form of metabolism as inorgoxidation (oxidation of inorganic compounds).

Another contributor, who continued to study it was Selman Waksman.
Primitive bacteria that live around deep ocean volcanic vents oxidize hydrogen sulfide for their nutrition, as discovered by Robert Ballard.
Sulphur oxidizers can use as energy sources reduced Sulphur compounds, including hydrogen sulfide, elemental sulphur, sulfite, thiosulfate, and various polythionates (e.g., tetrathionate).
Sulphur oxidizers depend on enzymes such as Sulphur oxygenase and sulfite oxidase to oxidize Sulphur to sulfate. 

Some lithotrophs can even use the energy contained in Sulphur compounds to produce sugars, a process known as chemosynthesis. 
Some bacteria and archaea use hydrogen sulfide in place of water as the electron donor in chemosynthesis, a process similar to photosynthesis that produces sugars and utilizes oxygen as the electron acceptor. 
Sulphur-based chemosynthesis may be simplifiedly compared with photosynthesis:
H2S +CO2 → sugars + S
H2O + CO2 → sugars + O2

There are bacteria combining these two ways of nutrition: 
*green Sulphur bacteria 
*purple Sulphur bacteria.
Also sulph-oxidizing bacteria can go into symbiosis with larger organisms, enabling the later to use hydrogen sulfide as food to be oxidized. 
There are sulfate-reducing bacteria, that, by contrast, "breathe sulfate" instead of oxygen. 

They use organic compounds or molecular hydrogen as the energy source. 
They use Sulphur as the electron acceptor, and reduce various oxidized Sulphur compounds back into sulfide, often into hydrogen sulfide. 
They can grow on other partially oxidized Sulphur compounds (e.g. thiosulfates, thionates, polysulfides, sulfites). 
A common myth exists, that hydrogen sulfide produced by these bacteria is responsible for some of the smell of intestinal gases (flatus) and decomposition products. 

Often flatus smells otherwise than hydrogen sulfide (which has rotten eggs smell, and still is present in human intestine), but the presence of these bacteria leads to a side effect out of the use of iron supplement, blackening of teeth and feces, that is caused by iron sulfide produced by those bacteria.
There are studies pointing that many deposits of native Sulphur in places that were the bottom of the ancient oceans have biological origin.
These studies indicate that this native Sulphur have been obtained through biological activity, but what is responsible for that (sulphur-oxidizing bacteria or sulfate-reducing bacteria) is still unknown for sure.

Sulphur is absorbed by plants roots from soil as sulfate and transported as a phosphate ester. 
Sulfate is reduced to sulfide via sulfite before Sulphur is incorporated into cysteine and other organosulphur compounds.
SO42− → SO32− → H2S → cysteine → methionine
While the plants' role in transferring Sulphur to animals by food chains is more or less understood, the role of Sulphur bacteria is just getting investigated.

-Protein and organic cofactors:
In all forms of life, most of the Sulphur is contained in two proteinogenic amino acids (cysteine and methionine), thus the element is present in all proteins that contain these amino acids, as well as in respective peptides.
Some of the Sulphur is comprised in certain metabolites, many of which are cofactors.
Proteins, to execute their biological function, need to have specific space geometry. 

Formation of this geometry is performed in a process called protein folding, and is provided by intra- and inter-molecular bonds. 
The process has several stages. 
While at premier stages a polypeptide chain folds due to hydrogen bonds, at later stages folding is provided (apart from hydrogen bonds) by covalent bonds between two Sulphur atoms of two cysteine residues (so called disulfide bridges) at different places of a chain (tertriary protein structure) as well as between two cysteine residues in two separated protein subunits (quaternary protein structure). 
Both structures easily may be seen in insulin. 

As the bond energy of a covalent disulfide bridge is higher than the energy of a coordinate bond or hydrophylic either hydrophobic interaction, the higher disulfide bridges content leads the higher energy needed for protein denaturation. 
There is an opinion, that disulfide bonds are necessary in proteins functioning outside cellular space, and they don't change proteins' conformation (geometry), but serve as its stabilizers. 
Within cytoplasm cysteine residues of proteins are saved in reduced state (i.e. in -SH form) by thioredoxins.
This property manifests in following examples. 

Lysozyme is stable enough to be applied as a drug.
Feathers and hair have relative strength, and consisting in them keratin is considered indigestible by most organisms. 
However, there are fungi and bacteria containing keratinase, and are able to destruct keratin.
Many important cellular enzymes use prosthetic groups ending with -SH moieties to handle reactions involving acyl-containing biochemicals: two common examples from basic metabolism are coenzyme A and alpha-lipoic acid.

Cysteine-related metabolites homocysteine and taurine are other sulphur-containing amino acids that are similar in structure, but not coded by DNA, and are not part of the primary structure of proteins, take part in various locations of mammalian physiology.
Two of the 13 classical vitamins, biotin, and thiamine, contain sulphur.
In intracellular chemistry, Sulphur operates as a carrier of reducing hydrogen and its electrons for cellular repair of oxidation. 
Reduced glutathione, a sulphur-containing tripeptide, is a reducing agent through its sulfhydryl (-SH) moiety derived from cysteine.

Methanogenesis, the route to most of the world's methane, is a multistep biochemical transformation of carbon dioxide. 
This conversion requires several organosulphur cofactors. 
These include coenzyme M, CH3SCH2CH2SO3−, the immediate precursor to methane.

-Metalloproteins and inorganic cofactors:
Metalloproteins in which the active site is a transition metal complex bound to Sulphur atoms are essential components of enzymes involved in electron transfer processes. 
Examples include blue copper proteins and nitrous oxide reductase. 
The function of these enzymes is dependent on the fact that the transition metal ion can undergo redox reactions. 

Other examples include iron–sulphur clusters as well as many copper, nickel, and iron proteins. 
Most pervasive are the ferrodoxins, which serve as electron shuttles in cells. 
In bacteria, the important nitrogenase enzymes contains an Fe–Mo–S cluster and is a catalyst that performs the important function of nitrogen fixation, converting atmospheric nitrogen to ammonia that can be used by microorganisms and plants to make proteins, DNA, RNA, alkaloids, and the other organic nitrogen compounds necessary for life.

HISTORY of SULPHUR:
-Antiquity:
Being abundantly available in native form, Sulphur was known in ancient times and is referred to in the Torah (Genesis). 
English translations of the Christian Bible commonly referred to burning Sulphur as "brimstone", giving rise to the term "fire-and-brimstone" sermons, in which listeners are reminded of the fate of eternal damnation that await the unbelieving and unrepentant. 
Sulphur is from this part of the Bible that Hell is implied to "smell of Sulphur" (likely due to Sulphur's association with volcanic activity). 
According to the Ebers Papyrus, a Sulphur ointment was used in ancient Egypt to treat granular eyelids. 

Sulphur was used for fumigation in preclassical Greece; this is mentioned in the Odyssey.
Pliny the Elder discusses Sulphur in book 35 of his Natural History, saying that its best-known source is the island of Melos. 
He mentions Sulphur's use for fumigation, medicine, and bleaching cloth.
A natural form of Sulphur known as shiliuhuang was known in China since the 6th century BC and found in Hanzhong.
By the 3rd century, the Chinese had discovered that Sulphur could be extracted from pyrite.
Chinese Daoists were interested in sulphur's flammability and its reactivity with certain metals, yet its earliest practical uses were found in traditional Chinese medicine.

A Song dynasty military treatise of 1044 AD described various formulas for Chinese black powder, which is a mixture of potassium nitrate (KNO3), charcoal, and sulphur. 
Sulphur remains an ingredient of black gunpowder.
Indian alchemists, practitioners of the "science of chemicals" (Sanskrit: रसशास्त्र, romanized: rasaśāstra), wrote extensively about the use of Sulphur in alchemical operations with mercury, from the eighth century AD onwards.
In the rasaśāstra tradition, Sulphur is called "the smelly" (गन्धक, gandhaka).