Sodium hydroxide world production

Sodium Hydroxide. Before World War 1, nearly all sodium hydroxide [1310-93-2], NaOH, was produced by the reaction of soda ash and lime. The subsequent rapid development of electrolytic production processes, resulting from growing demand for chlorine, effectively shut down the old lime—soda plants except in Eastern Europe, the USSR, India, and China. Recent changes in chlorine consumption have reduced demand, putting pressure on the price and availabiHty of caustic soda (NaOH). Because this trend is expected to continue, there is renewed interest in the lime—soda production process. EMC operates a 50,000 t/yr caustic soda plant that uses this technology at Green River it came onstream in mid-1990. Other U.S. soda ash producers have aimounced plans to constmct similar plants (1,5). 

Sir Humphry Davy first isolated metallic sodium ia 1807 by the electrolytic decomposition of sodium hydroxide. Later, the metal was produced experimentally by thermal reduction of the hydroxide with iron. In 1855, commercial production was started usiag the DeviUe process, ia which sodium carbonate was reduced with carbon at 1100°C. In 1886 a process for the thermal reduction of sodium hydroxide with carbon was developed. Later sodium was made on a commercial scale by the electrolysis of sodium hydroxide (1,2). The process for the electrolytic decomposition of fused sodium chloride, patented ia 1924 (2,3), has been the preferred process siace iastallation of the first electrolysis cells at Niagara Falls ia 1925. Sodium chloride decomposition is widely used throughout the world (see Sodium compounds). 

The Dow Chemical Company in the mid-1920s developed two processes which consumed large quantities of chlorobenzene. In one process, chlorobenzene was hydrolyzed with ammonium hydroxide in the presence of a copper catalyst to produce aniline [62-53-3J. This process was used for more than 30 years. The other process hydrolyzed chlorobenzene with sodium hydroxide under high temperature and pressure conditions (4,5) to product phenol [108-95-2]. The LG. Earbenwerke in Germany independentiy developed an equivalent process and plants were built in several European countries after World War II. The ICI plant in England operated until its dosing in 1965. 

At present about 77% of the industrial hydrogen produced is from petrochemicals, 18% from coal, 4% by electrolysis of aqueous solutions and at most 1% from other sources. Thus, hydrogen is produced as a byproduct of the brine electrolysis process for the manufacture of chlorine and sodium hydroxide (p. 798). The ratio of H2 Cl2 NaOH is, of course, fixed by stoichiometry and this is an economic determinant since bulk transport of the byproduct hydrogen is expensive. To illustrate the scde of the problem the total world chlorine production capacity is about 38 million tonnes per year which corresponds to 105000 toimes of hydrogen (1.3 x I0 m ). Plants designed specifically for the electrolytic manufacture of hydrogen as the main product, use steel cells and aqueous potassium hydroxide as electrolyte. The cells may be operated at atmospheric pressure (Knowles cells) or at 30 atm (Lonza cells). 

The simultaneous reaction of sulfur dioxide and chlorine with paraffins, named sulfochlorination, was discovered by Reed and Horn in the 1930s [9]. The primary products of this reaction are the alkanesulfochlorides [10], which can be saponified to alkanesulfonates by sodium hydroxide solution or treated with substituted phenolates to give plasticisers. In a short time the process was industrially realized to secure detergent production during World War II in Germany [11]. 

Chemists are not the only ones who make use of acid-base chemistry. In fact, most of the chemical manufacturing that goes on in the world is related to the production of four simple, but very useful, products—sulfuric acid, phosphoric acid, sodium hydroxide, and sodium chloride. 

This term was originally intended to denote all kinds of man-made textile fibres, but is now applied only to cellulose types. Viscose rayon (regenerated from a solution of cellulose xanthate in sodium hydroxide) accounts for the greater part of world rayon production. Acetate rayon and cuprammonium rayon are relatively unimportant. 

Sodium chloride is found in salt beds, salt brines, and sea water throughout the world, and it is also mined is some locations. Consequently, sodium chloride is the source of numerous other sodium compounds. A large portion of the sodium chloride utilized is consumed in the production of sodium hydroxide (Eq. (11.23)). The production of sodium metal involves the electrolysis of the molten chloride, usually in the form of a eutectic mixture with calcium chloride. Sodium carbonate is an important material that is used in many ways such as making glass. It was formerly produced from NaCl by means of the Solvay process, in which the overall reaction is... 

Meanwhile the use of electricity as a means of bringing about chemical change continued to play a central role in the development of chemistry. HUMPHREY Davey prepared the first elemental sodium by electrolysis of a sodium hydroxide melt. It was left to Davey s former assistant, MICHAEL FARADAY, to show that there is a direct relation between the amount of electric charge passed through the solution and the quantity of electrolysis products. JAMES CLERK Maxwell immediately saw this as evidence for the molecule of electricity , but the world would not be receptive to the concept of the electron until the end of the century. 

Chlor-alkali production — With a 63% production volume of the total world chlorine capacity of about 43.4 million tons (in 1998), the chlor-alkali (or chlorine-caustic) industry is one of the largest electrochemical technologies in the world. Chlorine, Cl2, with its main co-product sodium hydroxide, NaOH, has been produced on industrial scale for more than a century by -> electrolysis of brine, a saturated solution of sodium chloride (-> alkali chloride electrolysis). Today, they are among the top ten chemicals produced in the world. Sodium chlorate (NaC103) and sodium hypochlorite (NaOCl, bleach ) are important side products of the... 

Chlorine and caustic soda (sodium hydroxide) are among the top ten commodity chemicals produced in the world. In 2004, North America produced about 29 million tons of chlorine and caustic soda.18 Figure 26.5 shows the global production of chlorine by region in 2004. 

Sodium chloride is used more often than any other material in the manufacture of inorganic chemicals. World consumption of this substance is about 150 million tons per year. The major use of sodium chloride is in the production of other essential inorganic chemicals such as chlorine gas, sodium hydroxide, sodium metal, hydrogen gas, and sodium carbonate. It is also used to melt ice and snow on highways and roads. However, since sodium chloride is harmful to plant life and promotes corrosion of cars, its use for this purpose is of considerable environmental concern. 

In 1865 just prior to Kekule s synthesis of phenol, Joseph Lister (1827-1912) was experimenting with carbolic acid as an aid to antiseptic surgery which he had pioneered. A mixture of crystallised carbolic acid and shellac (lac plaster) was employed in the finally adopted mode of application. The requirement of phenol for the manufacture of picric acid during the Boer war and other uses resulted in a demand which soon outstripped the resources of phenol/cresols available from coal distillation. Synthetic phenol thus became a potentially important intermediate. The lengthy processing involved in the separation of phenol and the isomeric cresols led to the desirability for specific syntheses. In 1978 of the world production of phenol only 3% came from coal sources by extraction of the mixed phenols (about 1.5% in coal tar) with 10% sodium hydroxide, acidification with carbon dbxide and separation. Phenolic compounds are also formed during catalytic cracking processes in the petroleum industry. There are historically six industriai processes for the production of synthetic phenol, variously from benzene and toluene, some of which are also applicable to the cresols and the dihydric phenols. 

Commercial alumina is produced chiefly from bauxite, the total world production being millions of tons per year. The bauxite ore contains, besides oxides of aluminium, silica and ferric oxide, which are removed by the Bayer method as follows. First the ore is ground fine, and it is then treated with sodium hydroxide solution in an iron autoclave under a pressure of 4 atm and at 160°—170°C. The alumina dissolves, forming sodium aluminate ... 

The chlor-alkali industry is one of the largest electrochemical operations in the world, the main products being chlorine and sodium hydroxide generated simultaneously by the electrolysis of sodium chloride solutions. The chlor-alkali industry serves the commodity chemical business, chlorine and sodium hydroxide (also called caustic soda) being indispensable intermediates in the chemical industry [1-10]. 

Chlorine and sodium hydroxide (or caustic soda) are among the top 10 chemicals produced in the world, and are involved in the manufacturing of a myriad of products that are used in day-to-day life. These products include pharmaceuticals, detergents, deodorants, disinfectants, herbicides, pesticides, and plastics. 

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