Process Solvay

Early demand for chlorine centered on textile bleaching, and chlorine generated through the electrolytic decomposition of salt (NaCl) sufficed. Sodium hydroxide was produced by the lime—soda reaction, using sodium carbonate readily available from the Solvay process. Increased demand for chlorine for PVC manufacture led to the production of chlorine and sodium hydroxide as coproducts. Solution mining of salt and the avadabiHty of asbestos resulted in the dominance of the diaphragm process in North America, whereas soHd salt and mercury avadabiHty led to the dominance of the mercury process in Europe. Japan imported its salt in soHd form and, until the development of the membrane process, also favored the mercury ceU for production. 

These disadvantages prompted Ernest Solvay (1838—1922) to develop and commercialize a procedure using ammonia to produce soda ash from salt and limestone. The first plant using the Solvay process was built in 1863 this process or variations are in use in much of the world in the 1990s. 

The basic Solvay process remains the dominant production route for soda ash. Its continued success is based on the raw matedals, salt and limestone, being more readily available than natural alkaU. AH soda ash processes are based on the manipulation of saline phase chemistry (6,7) an understanding of which is important both to improving current processes and to the economic development of new alkaU resources. 

The ammonium chloride process, developed by Asahi Glass, is a variation of the basic Solvay process (9—11). It requires the use of soHd sodium chloride but obtains higher sodium conversions (+90%) than does the Solvay process. This is especially important ia Japan, where salt is imported as a soHd. The major difference from the Solvay process is that here the ammonium chloride produced is crystallized by cooling and through the addition of soHd sodium chloride. The resulting mother Hquor is then recycled to dissolve additional sodium chloride. The ammonium chloride is removed for use as rice paddy fertilizer. Ammonia makeup is generally suppHed by an associated synthesis plant. 

Akzo Process. Akzo Zout Chemie has developed a route to vinyl chloride and soda ash from salt usiag an amine—solvent system catalyzed by a copper—iodide mixture (13). This procedure theoretically requires half the energy of the conventional Solvay processes. 

Sodium bicarbonate may be prepared by the ammonia-salt (Solvay) process. Carbon dioxide is passed through a solution of sodium chloride in ammonia water. Sodium bicarbonate is precipitated and the ammonium chloride remains in solution. The ammonium chloride is heated with lime to regenerate ammonia (see Alkali AND CHLORINE PRODUCTS). 

The amount of soda ash, Na2C02, produced by the Solvay process has decreased, and most soda ash now comes from the Trona, Wyoming deposits (trona, Na2C02 NaHCO 2H20). Caustic soda, NaOH, solutions may be used ia wet batchiag processes as a source of soda (see Alkali and... 

Alkalies. In the 1960s, 3.2-34 x 10 t /yr of lime was captively produced by the U.S. alkaH industry for manufacturing soda ash and sodium bicarbonate via the Solvay process. Electrolytic process caustic soda and natural soda ash (trona) from Wyoming have largely replaced the Solvay process. Three of the trona producers in Wyoming now purchase quicklime for producing caustic soda. 

A.mmonia-Soda Process. Ammonium chloride is made as a by-product of the classic Solvay process, used to manufacture sodium carbonate (12,13) (see Alkali and chlorine products, sodium carbonate). The method iuvolves reaction of ammonia, carbon dioxide, and sodium chloride ia water... 

Other Applications. Among other industrial uses of lime are causticizing agent in kraft (sulfate) paper (qv) plants recovery of ammonia (qv) from NH4CI (Solvay process) recovery of magnesium (qv) from seawater and brines via precipitation of Mg(OH)2 production of pesticides such as... 

A former commercially important source of calcium chloride was as a by-product of the Solvay process used to produce soda ash (28). Because of environmental concerns and high energy costs, the Solvay process has been discontinued ia the United States though it is stiU used extensively elsewhere ia the world (see Calcium compounds). 

In 1976, over 3,000,000 tons of soda ash were produced in the United States using the Solvay process. This process has been discontinued in the United States because of pollution problems and high processing costs. It is stUl an important process in other countries. 

Ammonia is a cyclic reagent that is recovered by the end of the Solvay process for sodium carbonate from hme and salt. Although there is nothing obscure about the intermediate reactions, ammonia definitely participates in a catalytic sequence. 

Startup flow to the expander is designed to be supplied from the discharge of the compressor through a throttle valve and cooler. A careful study of the characteristics of the compressor blow-off valve and the expander startup valve was performed by Solvay process engineers. Based on these calculations, the startup cooler and valve were sized to supply the minimum required flow to tlie expander wheel. 

Sodium bicarbonate is made by the carbonation of salt and ammonia in carbonation tower (Solvay process) ... 

Residual catalyst (expressed as ash content). The actual residues depend on the manufacturing process used and on the characteristics of the polymer. The so-called new generation HD-PE processes such as the Solvay process use superactive catalysts which produce polymers with a low ash content and, hence, low or negligible odor. Some narrow MWD (Molecular Weight Distribution) resins also have lower catalyst residues than their wide MWD counterparts. 

About 95% of the sodium carbonate used in the U.S. is mined, primarily in Wyoming. The ore is known as trona and needs only to be heated to produce commercial soda ash. Elsewhere in the world it is made by the Solvay process, which uses limestone and salt as raw materials. Calcium chloride is a byproduct of the Solvay process. 

C04-0106. The Solvay process is a commercial method for producing sodium carbonate. In one step of this... 

This method of making soda ash is called the Solvay process. Discovered in 1861 by Belgian businessman Ernest Solvay (1838-1922), the Solvay process was used in the commercial production of soda ash in the 1870s, and it is still in use today. Soda ash is used in the manufacture of glass and soap. It is also used in the bleaching process for paper and cloth. 

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... 

Although the Solvay process is still in use in some parts of the world, the chief source of sodium carbonate is the mineral trona, Na2C03 NaHC03 2H20. 

Another indispensable carbonate is sodium carbonate, which is also known as soda ash. Centuries ago, impure sodium carbonate was obtained from the places where brine solutions had evaporated and from dry lake beds. The major source of soda ash today is once again from a natural source, but prior to 1985, it was synthesized in large quantities. The synthetic process most often used was the Solvay process, represented by the equations... 

Ammonia-soda Also called the Solvay process. A process for making sodium carbonate. The basic process was invented and partially developed in the first half of the 19th century by several workers, but the key invention was made by E. Solvay in Belgium in 1861. The first plant was built at Couillet, Belgium, in 1864 and thereafter the process became accepted worldwide, displacing the Leblanc process. The raw materials are limestone and salt calcium chloride is a waste product. The overall reaction is ... 

Chance Also called Chance-Claus. A process for recovering sulfur from the calcium sulfide residues from the Leblanc process. Treatment of a suspension of the residues with carbon dioxide generates hydrogen sulfide, which is converted to sulfur dioxide by the Claus proces. The sulfur dioxide is converted to sulfuric acid. Developed by A. M. and J. F. Chance 1882 to 1887 and widely used until the Leblanc process was superseded by the Solvay process. 

Fresnel A predecessor of the Solvay process, proposed by A. J. Fresnel in France in 1811. 

The sodium nitrate was used as a fertilizer. The evolution of the process was complex the book referenced below lists 63 patents relating to it. It was installed by the Solvay Process Company at Hopewell, VA in the 1930s it was in operation there, subsequently under the management of the Allied Chemical Corporation until the 1950s. 

Schloesing-Rolland An early variant of the ammonia-soda process for making sodium carbonate. Operated near Paris in 1857 and then in Middlesbrough, England, for approximately 20 years until supplanted by the Solvay process. 

Solvation properties, of supercritical solvents, 14 80-81 Solvatochromic materials, 22 708t Solvatochromic probes, 26 853—855 Solvatochromic spectral shifts, 23 96 Solvatochromy, 20 517 Solvay, 7 641 Solvay process, 15 63... 

Sodium carbonate (Na CO ) is the eleventh most used industrial chemical in the United States. It is commonly used as a bleaching agent and is manufactured in a two-step process. First, ammonia is combined with carbon dioxide to form sodium chloride and water, which reacts to form sodium bicarbonate and ammonium chloride (NH + CO + NaCl + H O —> NaHCOj + NH Cl). Sodium bicarbonate, commonly known as baking soda, is used as a leavening agent in baking, as an antacid to relieve stomach acid, and as a component for fire extinguishers. The second step is known as the Solvay process, wherein the sodium bicarbonate is heated and converted into sodium carbonate (NaHCO A— Na CO + H O + CO ). 

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