An introduction to sulfur

Historically, the chain of sulfur products has been used by people for a long time. But the growth of its consumption is related to the 13th century AD. During that period, the Chinese discovered a black powder containing sulfur. With the development of chemical knowledge in the 11th century AD and its transformation into an industry in the 11th century AD, sulfur became known as a source of sulfuric acid production. An acid that plays an important role in today’s life. In the past, volcanic lava, especially in Sicily, Italy, was considered the most important source of sulfur supply. But later, with the discovery of the possibility of extracting this product from underground mines, its supply sources changed. Today, Canada, Holland, Spain, China and America have the largest amount of sulfur reserves in the world. It should be noted that most of Iran’s sulfur deposits are combined with sour gases and oil sources, which are produced and exported in large quantities today. Among the most important metamorphic sulfur deposits in Iran, in order of their reserves, are Bastane deposit in the west of Bandar Lange, Khemer deposit in the northwest of Khemer port, Dastkede deposit in the western end of Qeshm Island, Al-Tidan deposit in the west of Bandar Abbas, West Bandar Abbas deposit and Dalzian deposit in the south. Shargh Semnan pointed out. Sulfur is directly and indirectly used in various industries such as agricultural fertilizers, paints, paper, leather, fibers, explosives, pharmaceuticals, rubber, cleaners, batteries, etc., and currently more than 54% of sulfur produced in the world comes from Oil and gas are obtained. Isfahan Oil Refining Company, as one of the largest producers of petroleum products in the country, produces a significant amount of sulfur as a by-product during the process of refining petroleum and producing petroleum products. The purpose of these studies is to obtain a set of sulfur products that have What can be seen in this report is the market, technical, financial, and economic evaluation of the selected products of the project, which were selected in the course of the studies. The reports of each of the selected units are presented separately in the attachments. Sulfur production capacity in the northern refinery In the developed capacity, it is equal to 134 tons per day (equivalent to 444.03 tons per year) for 334 production days per year. The production of selected products should be used in this section. The selected products in the hydrogen sulfide sector are: • Sodium sulfide (Na2S) • Wet sulfuric acid (WSA) • Ammonium sulfate (AS) • Potassium sulfate (SOP) Sulfur production capacity in the South Refinery is currently equal to 154 tons per day. It is equivalent to 544,09 tons per year for 334 production days per year. This capacity will increase to 014 tons per day in the next 3 years (equivalent to 151,044 tons per year). be spent on the production of the following selected products: • Bentonite sulfur (SB) (Mic S), micronized sulfur • It was also decided that in the second phase, the rest of the sulfur produced (equivalent to 334 tons per day) will be spent on the production of the following products: • Sulphonic acid (LABSA) • Sulfuric acid • Sulfur covered urea (SCU) • Simple superphosphate (SSP)

Appearance characteristics of sulfur

The appearance of this nonmetal is pale yellow, which is very light and soft. This element has a specific smell when combined with hydrogen, which is similar to the smell of rotten eggs. [9] Sulfur burns with a blue flame and emits a strange smell (see the picture). Sulfur does not dissolve in water, but it dissolves in carbon disulfide (two carbon sulfur). [5] The usual oxidation states of this element are 2-, 2+, 4+, and 6+, which reduce 2- and 4+, and tend to reach 6+, which is more stable. and the 4+ and 6+ states do not follow the rule of eight. [10] Sulfur has multiple forms in all liquid, solid and gas states, the relationship between which is still not fully understood. Crystalline sulfur is shown as sulfur ring S8.
Polymeric sulfur nitride has metallic properties, even though it does not contain any metal atoms (it is quasi-metal).[5] This element also has unusual optical and electrical properties. Amorphous or plastic sulfur is obtained by rapid cooling of sulfur crystals. X-ray studies show that the amorphous, disordered species may have 8 atoms per star-like twist structure.
Sulfur can be obtained in two crystal states, orthorhombic (octahedron sulfur) or monoclinic crystal, the first of which is more stable at normal temperatures.[10]


Sulfur has many applications in free form and in combination, but its most use is for making chemical compounds and intermediate products in the industrial cycle. The most sulfur consumption in previous years was in agricultural industries and preparation of phosphatic fertilizers.
Sulfur is one of the components of gunpowder. Sulfur is also used for welding rubber. [3] Sulfur is used as a fungicide as well as disinfectant and fertilizer. Sulfur is also used to prepare sulfuric acid. [50][51] Sulfur is also used to make several The type of paper is used as a bleaching material and as an electrical insulator.
Sulfur compounds are highly toxic, for example, a small amount of hydrogen sulfide can alter the body’s metabolism, but larger amounts can quickly cause death by respiratory paralysis. Hydrogen sulfide quickly destroys the sense of smell. Sulfur dioxide is an important air pollutant. [52][53] This element is produced for industrial uses such as the production of sulfuric acid (H2SO4) for batteries, gunpowder production, and rubber heating. Sulfur acts as an antifungal agent in the production process of phosphate fertilizers. Sulfates are also used in washing and drying papers. Sulfur is also used in making matches and fireworks. Ammonium or sodium thiosulfate is used as a fixing agent in photography. Magnesium sulfate can be used as an anti-drying and laxative agent, which is a herbal magnesium supplement

Application of sulfur in agriculture
The highest consumption of sulfur in previous years was related to agricultural industries and preparation of phosphatic fertilizers. Sulfur is considered as the most important mineral needed for plant growth, and its deficiency has a bad effect on agricultural products. In this industry, sulfur is used to make chemical fertilizers healthy and nutritious, as well as to supply nutrients needed by plants from other sources.

Application of sulfur in medicine
From the use of sulfur in medicine, we can mention the production of antioxidants, anti-allergic substances and some drugs used to treat cough or bronchitis.
Application of sulfur in steel industry
Sulfur is used in the production and manufacture of stainless steel. Like production:
• 304 steel rebar
• 316 steel rebar
• 321 steel rebar
• 410 steel rebar
• 420 steel rebar
• 430 steel rebar
• 4057 steel rebar
• 309 stainless steel rebar
• 310 stainless steel rebar
• 304 steel pipe
• 316 steel pipe
• 321 steel pipe
• 309 fireproof steel pipe
• 310 stainless steel pipe
• 309 steel sheet
• 304 steel sheet
• 310 steel sheet
• 316 steel sheet
• 410 steel sheet
• 420 steel sheet
• 430 steel sheet
Other uses of sulfur:
• Fungal killer as well as disinfectant and fertilizer
• Production of gunpowder
• Its application in rubber welding
• Production of sulfuric acid
• It is used to make several types of paper, a bleaching agent and as an electrical insulator
• Production of sulfuric acid (H2SO4) for batteries
• Making matches and fireworks
• Ammonium or sodium thiosulfate as a fixing agent in photography
• Magnesium sulfate as an anti-drying and laxative agent, which is a herbal magnesium supplement
• Beauty and cosmetics

Sulfur metabolism and sulfur cycle

The sulfur cycle was the first biogeochemical cycle to be discovered. In the 1880s, while studying Begiotoa (a bacterium that lives in sulfur-rich environments), Sergei Vinogradsky discovered that this bacterium oxidizes hydrogen sulfide (H2S) as an energy source and replenishes intracellular sulfur droplets. Vingradsky named this form of oxidation metabolism of mineral compounds (inorgoxidation) and worked on it with Salman Waxman until the 1950s.

Sulfur oxidizers can be used as an energy source. These include hydrogen sulfide, pure sulfur, sulfite, thiosulfate, and several polythionates (such as tetrathionate). [29] They rely on enzymes such as sulfur deoxygenase and sulfite oxidase to oxidize sulfur to sulfate. Some bacteria and archaea use hydrogen sulfide in water as an electron donor to perform chemical synthesis. A process similar to photosynthesis and the result will be sugar and they use oxygen as an acceptor atom. Photosynthesizing green sulfur bacteria and purple sulfur bacteria use pure oxygen to carry out such oxidation to make sulfur from hydrogen sulfide. Primitive bacteria that live in the deep oceans next to hydrothermal vents oxidize hydrogen sulfide. The giant ringworm is an example of a large organism that uses hydrogen sulfide as food.

Sulfate-reducing bacteria “breathe” sulfate instead of oxygen. They use inorganic compounds or molecular hydrogen as an energy source and use sulfur as an electron acceptor and reduce sulfur oxides to sulfide (typically hydrogen sulfide). They can grow on other oxidized sulfur groups such as thiosulfate, thionate, polysulfides, and sulfites. The hydrogen sulfide produced by these bacteria causes flatulence.

Sulfur absorbed by plants that absorb it in the form of sulfate through the roots from the soil. Sulfate is reduced to sulfide and then incorporated into cysteine and other organic sulfur compounds.

SO42– → SO32– → H2S → Cysteine → Methionine