Read More: EU disagreements delay regulation of harmful chemicals. There was one technical hurdle that threatened to sink the profits of a new textile pigment industry.
The problem was solved by a comprehensive research program implemented by the large German industry group BASF Badische Anilin und Soda Fabrikation and led by the industrial chemist Rudolf Knietsch to in the s. Under normal circumstances, the combustion products of sulphuric acid, sulphur dioxide SO 2 , does not bind with oxygen in the air. But the German chemist showed that it can be achieved by contact with a suitable catalyst, such as platinum or vanadium oxide V 2 O 5.
BASF and another German manufacturer, Hoechst, established the first industrial plant based using the contact process in the mid s. Sulphuric acid is probably not a common household product. It is probably best known as battery acid, which together with distilled water is used in car batteries. But this does not change the fact that our society depends on it.
Sulphuric acid is an immeasurably important chemical, but it is not a good idea to come too close. We can be glad that we do not live on Venus, where not only is the surface temperature a searing degrees centigrade, but the atmosphere is formed of carbon dioxide and sulphuric acid. Read this article in English on ForskerZonen, part of Videnskab. Helge Kragh. Large volcanic eruptions have cooled the global climate many times in the last 2, years and coincided with devastating famine across Europe, new research shows.
Bacteria within the Greenland ice sheet are adapting to cope with pollutants deposited in the ice. These same bacteria may be key to removing some of this contamination before it enters the local food chain. Ocean temperatures were cooling for almost two millennia but then human industrialisation came along.
The Arctic may be a long way from the industrial world, but harmful chemical substances find their way northward and concentrate in animals there. Researchers have now found a disturbing trend: concentrations of one harmful chemical family are higher in thin Arctic foxes than in their more well-fed brethern.
Read about new methods for managing stress in working life. Two researchers tell the story of how the pandemic completely altered their research topic and how they dealt with it. Photo: Shutterstock. November - BASF pioneered the modern production of sulphuric acid. The first photograph of Venus' sulphuric acid surface and atmosphere, taken on the 22nd October by a Russian space probe.
Photo: Venera-9 lander, Russian Space Agency. This is called fuming sulphuric acid or Oleum or Nordhausen acid. Sulphuric acid has many applications, including in many chemical reactions and production processes. It is the most widely used chemical. Principal uses include fertilizer manufacturing, ore processing, chemical synthesis, wastewater processing and oil refining.
In combination with nitric acid it forms the nitronium ion, which is used in the nitration of compounds. The process of nitration is used to manufacture a great many explosives, including trinitrotoluene, nitroglycerine, and guncotton. It is also the acid used in lead-acid batteries, and so is sometimes known as battery acid. The energy of the hydration reaction with sulphuric acid is highly exothermic, and if water is added to concentrated sulphuric acid it can boil.
Always add the acid to the water rather than the water to the acid. Note that part of this problem is due to the relative densities of the two liquids.
Water is less dense than sulfuric acid and will tend to layer above the acid, and not mix well, if added to the acid.
Because the hydration of sulfuric acid is thermodynamically favourable, sulphuric acid is an excellent dehydration agent, and is used to prepare many dried fruits. They are washed with cooled concentrated acid from the Glover tower ; the nitrogen oxides and unreacted sulfur dioxide dissolve in the acid to form the nitrous vitriol used in the Glover tower.
Remaining waste gases are usually discharged into the atmosphere. History of sulfuric acid Sulfuric acid was known to medieval alchemists under of variety of names including oil of vitriol and spirit of vitriol. These substances were produced by the dry distillation of minerals including ferrous sulfate heptahydrate, FeSO 4 , 7H 2 O, called green vitriol, and cupric sulfate pentahydrate, CuSO 4 , 5H 2 O, called blue vitriol.
When heated, these compounds decompose to ferrous and cupric oxides, respectively, giving off water and sulfur trioxide, which combine to produce a dilute solution of sulfuric acid. Preparations like these have been ascribed to alchemists including the 12th-century Arab Abou Bekr al-Rhases and the 13th-century German Albertus Magnus. This raw material is shown below as fluorapatite , though the exact composition may vary.
The HF is removed as hydrofluoric acid. The overall process can be represented as:. Sulfuric acid is used in large quantities by the iron and steelmaking industry to remove oxidation, rust and scale from rolled sheet and billets prior to sale to the automobile and white-goods industry. These plants combust spent acid with natural gas, refinery gas, fuel oil or other fuel sources.
This combustion process produces gaseous sulfur dioxide SO 2 and sulfur trioxide SO 3 which are then used to manufacture "new" sulfuric acid. SAR plants are common additions to metal smelting plants, oil refineries, and other industries where sulfuric acid is consumed in bulk, as operating a SAR plant is much cheaper than the recurring costs of spent acid disposal and new acid purchases.
Ammonium sulfate , an important nitrogen fertilizer, is most commonly produced as a byproduct from coking plants supplying the iron and steel making plants. Reacting the ammonia produced in the thermal decomposition of coal with waste sulfuric acid allows the ammonia to be crystallized out as a salt often brown because of iron contamination and sold into the agro-chemicals industry.
Another important use for sulfuric acid is for the manufacture of aluminium sulfate , also known as paper maker's alum. This can react with small amounts of soap on paper pulp fibers to give gelatinous aluminium carboxylates , which help to coagulate the pulp fibers into a hard paper surface.
It is also used for making aluminium hydroxide , which is used at water treatment plants to filter out impurities, as well as to improve the taste of the water. Aluminum sulfate is made by reacting bauxite with sulfuric acid:. Sulfuric acid is used for a variety of other purposes in the chemical industry.
For example, it is the usual acid catalyst for the conversion of cyclohexanoneoxime to caprolactam , used for making nylon. It is used for making hydrochloric acid from salt via the Mannheim process. Much H 2 SO 4 is used in petroleum refining, for example as a catalyst for the reaction of isobutane with isobutylene to give isooctane , a compound that raises the octane rating of gasoline petrol.
Sulfuric acid is also important in the manufacture of dyestuffs , pigments such as titanium dioxide , solutions, and is the "acid" in lead-acid car batteries.
Sulfuric acid is also used as a general dehydrating agent in its concentrated form see Reaction with water. The sulfur-iodine cycle is a series of thermo-chemical processes used to obtain hydrogen. It consists of three chemical reactions whose net reactant is water and whose net products are hydrogen and oxygen. The sulfur and iodine compounds are recovered and reused, hence the consideration of the process as a cycle. This process is endothermic and must occur at high temperatures, so energy in the form of heat has to be supplied.
The sulfur-iodine cycle has been proposed as a way to supply hydrogen for a hydrogen-based economy. It does not require hydrocarbons like current methods of steam reforming. The sulfur-iodine cycle is currently being researched as a feasible method of obtaining hydrogen, but the concentrated, corrosive acid at high temperatures poses currently insurmountable safety hazards if the process were built on large-scale.
The discovery of sulfuric acid is credited to the 8th century Arabian chemist and alchemist , Jabir ibn Hayyan Geber. When heated, these compounds decompose to iron II oxide and copper II oxide , respectively, giving off water and sulfur trioxide , which combine to produce a dilute solution of sulfuric acid.
This method was popularized in Europe through translations of Arabic and Persian treatises, as well as books by European alchemists, such as the 13th-century German Albertus Magnus. Sulfuric acid was known to medieval European alchemists as oil of vitriol , spirit of vitriol , or simply vitriol , among other names. The word vitriol derives from the Latin vitreus, 'glass', referring to the glassy appearance of the sulfate salts, which also carried the name vitriol.
Salts called by this name included copper II sulfate blue vitriol, or rarely Roman vitriol , zinc sulfate white vitriol , iron II sulfate green vitriol , iron III sulfate vitriol of Mars , and cobalt II sulfate red vitriol. Vitriol was widely considered the most important alchemical substance, intended to be used as a philosopher's stone.
Highly purified vitriol was used as a medium for reacting other substances. This was largely because the acid does not react with gold , production of which was often the final goal of alchemical processes. The importance of vitriol to alchemy is highlighted in the alchemical motto, Visita Interiora Terrae Rectificando Invenies Occultum Lapidem which is a backronym meaning 'Visit the interior of the earth and rectifying i.
In the 17th century, the German-Dutch chemist Johann Glauber prepared sulfuric acid by burning sulfur together with saltpeter potassium nitrate , KNO 3 , in the presence of steam. As saltpeter decomposes, it oxidizes the sulfur to SO 3 , which combines with water to produce sulfuric acid.
In , Joshua Ward, a London pharmacist, used this method to begin the first large-scale production of sulfuric acid. In in Birmingham , John Roebuck adapted this method to produce sulfuric acid in lead -lined chambers, which were stronger, less expensive, and could be made larger than the previously used glass containers. This lead chamber process allowed the effective industrialization of sulfuric acid production.
After several refinements, this method remained the standard for sulfuric acid production for almost two centuries. However, the manufacture of some dyes and other chemical processes require a more concentrated product. Throughout the 18th century, this could only be made by dry distilling minerals in a technique similar to the original alchemical processes.
However, the expense of this process prevented the large-scale use of concentrated sulfuric acid. In , British vinegar merchant Peregrine Phillips patented the contact process , which was a far more economical process for producing sulfur trioxide and concentrated sulfuric acid.
Today, nearly all of the world's sulfuric acid is produced using this method. The corrosive properties of sulfuric acid are accentuated by its highly exothermic reaction with water. Hence burns from sulfuric acid are potentially more serious than those of comparable strong acids e. The danger is obviously greater with more concentrated preparations of sulfuric acid, but it should be remembered that even the normal laboratory "dilute" grade approx.
Solutions equal to or stronger than 1. Fuming sulfuric acid oleum is not recommended for use in schools due to it being quite hazardous. The standard first aid treatment for acid spills on the skin is, as for other corrosive agents, irrigation with large quantities of water. However, the acid should be neutralised first by rinsing with a base e.
0コメント