Sulfuric acid king of chemicals industrial production using contact process

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Sulfuric acid also known as oil of vitriol, battery acid, and king of chemicals produced using contact process used in the manufacture of fertilizers, explosives, dyes, petroleum products, lead-acid batteries

Text of Sulfuric acid king of chemicals industrial production using contact process

Sulfuric acid king of chemicals - industrial production using contact process

Sulfuric acid king of chemicals - industrial production using contact processPublished by


Sulfuric acidmolecular formula written as H2SO4, with other names includes oil of vitriol, battery acid, and king of chemicals. Sulfuric acid composed of hydrogen, oxygen, and sulfur and available forms include dilute sulfuric acid, concentrated sulfuric acid.Sulfuric acidis formed naturally by the oxidation of sulfide minerals, such as iron sulfide. On earth, sulfuric acid does not exist in a natural form. But on the planet Venus, there are lakes of the sulfuric acid exist. The sulfuric acid from lakes will evaporate to form clouds, leading to sulfuric acid rain on the Venerean surface.

Industrial Production Sulfuric acid is the largest volume industrial chemical produced in the world i.e., 200 million tons per year. 93-98 per cent (concentrated)sulfuric acidis used in the manufacture of fertilizers, explosives, dyes, petroleum products, domestic acidic drain cleaner, lead-acid batteries, mineral processing, fertilizer manufacturing, oil refining, wastewater processing, and chemical synthesis.International commerce ofsulfuric acid, lists sulfuric acid under Table II of the convention as a chemical frequently used in the illicit manufacture of narcotic drugs or psychotropic substances.

Sulfuric acid Lab and industrial MSDsIn laboratories or industries if you spill a drop of sulfuric acid on your hand, it will burn tissue instantly. It also causes skin dehydration. Other severe effects of sulphuric acid are fumes cause blindness, and damage the lungs if inhaled.Even dilute sulfuric acid is dangerous. While handling sulfuric acid following precautionary steps need to be followAlways wear thick glovesWear a lab coat or apronNever handle it on an open benchNever pour it / through out from the bottle

Precautions Cont Never pipette out with mouthAlways use a thick glass pipette with a rubber bulbSulfuric acid is often stored in concentrated formSulfuric acid has following propertiesSulphuric acid is a powerful protonating agent.Sulphuric acid is also a powerful dehydrating agent and is used to remove a molecule of water from many organic compounds.Dilute sulphuric acid is a strong dibasic acid forming two series of salts.Sulfuric acid reacts with most bases to give the corresponding sulfate.It can oxidize non-active tin and copper metals

Sulfuric acid production processThe production of sulfuric acid has come to be accepted throughout the world as a reliable barometer of industrial activity. Its universal use has made it indispensable, in the widest sense of the world, in chemical and process industries. Sulfuric acid is a strong acid i.e. is in aqueous solution its largely changed to hydrogen ions and sulfate ions. Each molecule gives 2 hydrogen ions and thus sulfuric acid is dibasic acid.The preparation by burning sulfur with saltpeter was first described by Valentinus in the fifteenth century. Later its preparation by distilling niter with green vitriol was mentioned by Persian alchemist Abu-Bekr-Ahhases, who died in 940.The weathering of iron pyrites was usually the source of green vitriol. Sulfuric acid has been an important item of commerce for at least 250 years and has been known and used since the Middle Ages.

Sulfuric acid production process Cont n the eighteenth and nineteenth centuries, it was essentially and entirely produced by chamber process, in which oxides of nitrogen (as nitrosyl compounds) were used as homogeneous catalysts for the oxidation of sulfur dioxide. The product made by this process was of rather low concentration not high enough for many commercial uses.In 1746, Roebuck of Birmingham, England produced successfully on commercial scale by burning sulfur and potassium nitrate in ladle suspended in a large glass partially filled with water.

Sulfuric acid production process Cont The contact process was first discovered in 1831 by Phillips, an Englishman whose patent included the essential features of the modern contact process namely the passing of the mixtureSO2over a catalyst followed by absorption of SO3in 98 to 99 per cent H2SO4. Later it was demonstrated that excess of oxygen in the gaseous mixture for contact process was advantageous. The contact process has been improved in all details and at the current scenario is one of the low cost industries and is almost wholly automatic continuous process for the manufacture of sulfuric acid.Primary impetus for the development of the contact process came from a need for high strength acid and oleum to make synthetic dyes and organic chemicals. The contact process employing platinum catalysts began to be used on large scale for this purpose late in the nineteenth century. Its development accelerated during the World War I to provide the concentrated mixtures of sulfuric and nitric acid for the production of explosives.Sulfuric Acid Production Using Contact ProcessContact processThe contact process is the current method of producing sulfuric acid in the high concentrations needed for industrial processes. Platinum was formerly employed as a catalyst for the reaction, but as it is susceptible to poisoning by arsenic impurities in the sulfur feedstock, vanadium oxide (V2O5) is now preferred.The sulfur dioxide is obtained by burning sulfur or by roasting sulphide ores in air. Purification of air andSO2is necessary to avoid catalyst poisoning. The sulfur dioxide, mixed with an excess of air, is purified and dried then passed through a series of converters where the catalyst is stored on shelves in a way which exposes the maximum possible surface area to the reacting gases.

Contact Process Cont .The oxidation is exothermic and operating temperature is maintained without external heating by using heat exchangers.After passing through the converters the gases are cooled and passed into an absorption tower where the sulfur trioxide dissolves in concentrated sulfuric acid. The product leaving the absorption tower is normally 100 per cent sulfuric acid. Some of it is diluted with water, cooled, and reirculated through the absorption tower. By controlling the dilution the contact process can be adapted to produce fuming sulfuric acid.

Reactions involved in contact processS(l) + O2(g) SO2(g)2SO2(g)+ O2(g) 2SO3 (g)SO3(g)+ H2SO4(l) H2S2O7 (l)H2S2O7(l)+ H2O(g) 2H2SO4(l)

Double Contact Double Absorption processAnother significant change in the contact process occurred in 1963, when Bayer AG announced the first large scale use of Double Contact Double Absorption process and granted several patents.In this process the product gasesSO2andSO3are passed through absorption towers twice to achieve further absorption and conversion ofSO2toSO3and production of higher grade sulfuric acid.

Double Contact Double Absorption process Cont ..SO2rich gases enter the catalytic converter, are converted to SO3, achieving the first stage of conversion. The exit gases from this stage contain bothSO2andSO3which are passed through intermediate absorption towers where sulfuric acid is trickled down packed columns andSO3reacts with water increasing the sulfuric acid concentration. Unreactive SO2comes out of the absorption tower.This stream of gas containingSO2, after necessary cooling is passed through the catalytic converter bed column again achieving up to 99.8 per cent conversion ofSO2toSO3and these gases are again passed through the final absorption column thus resulting high conversion ofSO2but also enabling production of higher concentration of sulfuric acid

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