Ammonium sulfates

Ammonium phosphate uses are shown in the Table 12.2. Table 12.2. Ammonium Phosphate Uses 

Ammonium sulfate (AS) is produced from many sources. The first commercial synthesis started around the time of World War I. Since then direct synthesis from ammonia and sulfuric acid has become a major production route. Ammonium sulfate is generated from several chemical processes. The nitrogen or sulfur values are recovered either to avoid pollution problems or to obtain a commercial return for these elements241. The basic chemical reaction is  

Some convention is employed in the sources of AS, mainly for the benefit of statisticians, who try to follow developments in the AS business. AS that is obtained from caprolactam or acrylonitrile manufacture is normally referred to as co-product. On the other hand, AS that is produced from coke ovens, flue gas desulphurization, smelter tail gas, sewage treatment, gypsum, waste acid from methyl methacrylate and from other chemical processes is usually termed byproduct241. 

Co-product and by-product AS production depends on the process that is used to make the primary product - as shown in Table 12.3. Small amounts of AS may also be recovered in other processes such as acrylonitrile, acrylamide, formic acid, hydrogen cyanide, hydroquinone and p-aminophenol, and from the neutralization of sulfuric acid used to make clays and catalysts for catalytic cracking242. 

Primary Product By-Production Ratio (tons AS oer ton Primary Product) 

Ammonium sulfate [(NH4)2S04, density 1.769] is a colorless crystalline solid that decomposes above 513°C and is soluble in water but insoluble in alcohol. 

Ammonium sulfate was originally manufactured by using sulfuric acid to scrub by-product ammonia from coke-oven gas, and much is still produced in this manner. Most of the ammonium sulfate produced is now made by reaction between synthetic ammonia and sulfuric acid. 

Where sulfur for sulfuric acid is at a premium, a process based on gypsum and carbon dioxide from combustion can be used  

Water is removed by evaporation, and the product is crystallized to large, white uniform crystals, melting point 513°C, with decomposition. Anhydrite (CaS04) can also be used in this process. 

Large quantities of ammonium sulfate are produced by a variety of industrial neutralization operations required for alleviation of stream pollution by free sulfuric acid (H2S04) as well as in the manufacture of caprolactam. Ammonium sulfate also is a byproduct of coke oven operations where the excess ammonia formed is neutralized with sulfuric acid to form the ammonium sulfate. 

Ammonium sulfate (uh-MOH-ni-um SUL-fate) is an odorless, colorless to white crystalline solid that occurs in nature as the mineral mascagnite. In 2004, 2.6 million metric tons (2.9 million short tons) of the compound were produced in the United States, placing it in 21st place among chemicals made in that year. More than 95 percent of the ammonium sulfate produced is used in the production of fertilizers. 

The primary method of preparation for ammonium sulfate is the direction reaction between ammonia gas (NH3) and sulfuric acid (H2S04). The ammonium sulfate produced in the reaction is recovered as white crystals after evaporation of the water present in the reaction mixture. Other methods of preparation are also used. For example, gypsum (CaS042H20) can be treated with ammonia (NH3) and carbon dioxide (C02) to generate ammonium sulfate. 

Ammonium sulfate. Red atoms are oxygen white atoms are 

Ammonium sulfate is used as a fertilizer because it sup-hydrogen blue atoms are plies nitrogen and sulfur, two nutrients that plants need to 

Gray Stick indicates double grow properly. Lesser quantities of the compound are utilized in water treatment plants where it is used to control the acidity of the water being processed. Among other uses of ammonium sulfate are  

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Organic compounds containing sulfur are very important. Calcium sulfur, ammonium sulfate, carbon disulfide, sulfur dioxide, and hydrogen sulfide are but a few of the many important compounds of sulfur. 

Terminal alkynes are only reduced in the presence of proton donors, e.g. ammonium sulfate, because the acetylide anion does not take up further electrons. If, however, an internal C—C triple bond is to be hydrogenated without any reduction of terminal, it is advisable to add sodium amide to the alkyne solution Hrst. On catalytic hydrogenation the less hindered triple bonds are reduced first (N.A. Dobson, 1955, 1961). 

Ceric sulfate, O.IA Ce(lV) to Ce(lll). Dissolve 63.26 g of cerium(lV) ammonium sulfate dihydrate in 500 mL of 2N sulfuric acid. Dilute the solution to 1 L and standardize against the... 

Iron(II) ammonium sulfate hexahydrate, Q.IN Le(II) to Le(III). Dissolve 39.2139 g of LeS04 2(NH4)2S04 hHjO in 500 mL of IN sulfuric acid and dilute to 1 L. If desired, check against standard dichromate or permanganate solution. 

Ammonium sulfate, (NH4)2S04—0.5N 33 g per liter saturated dissolve 780 g of (NH4)2S04 in water and make up to a liter. 

Foiin s mixture (for uric acid) dissolve 500 g of ammonium sulfate, 5 g of uranium acetate, and 6 mL of glacial acetic acid, in 650 mL of water. The volume is about a liter. 

Another reducing titrant is ferrous ammonium sulfate, Fe(NH4)2(S04)2 6H2O, in which iron is present in the +2 oxidation state. Solutions of Fe + are normally very susceptible to air oxidation, but when prepared in 0.5 M 1T2S04 the solution may remain stable for as long as a month. Periodic restandardization with K2Cr20y is advisable. The titrant can be used in either a direct titration in which the Fe + is oxidized to Fe +, or an excess of the solution can be added and the quantity of Fe + produced determined by a back titration using a standard solution of Ce + or... 

The purity of ferrous ammonium sulfate is determined by a redox titration with K2Gt207, using the weight of the reagents as the signal in place of volume. 

ALCOHOLS,HIGHERALIPHATIC - SURVEYANDNATURAL ALCOHOLSMANUFACTURE] (Vol4) -ammonium sulfate from [AMMONIUM COMPOUNDS] (Vol 2)... 

Acetonitrile also is used as a catalyst and as an ingredient in transition-metal complex catalysts (35,36). There are many uses for it in the photographic industry and for the extraction and refining of copper and by-product ammonium sulfate (37—39). It also is used for dyeing textiles and in coating compositions (40,41). It is an effective stabilizer for chlorinated solvents, particularly in the presence of aluminum, and it has some appflcation in... 

Mixed with additives, urea is used in soHd fertilizers of various formulations, eg, urea—ammonium phosphate (UAP), urea—ammonium sulfate (UAS), and urea—phosphate (urea + phosphoric acid). Concentrated solutions of urea and ammonium nitrate (UAN) solutions (80—85 wt%) have a high nitrogen content but low crystallization point, suitable for easy transportation, pipeline distribution, and direct spray appHcation. 

The ratio of reactants had to be controlled very closely to suppress these impurities. Recovery of the acrylamide product from the acid process was the most expensive and difficult part of the process. Large scale production depended on two different methods. If soHd crystalline monomer was desired, the acrylamide sulfate was neutralized with ammonia to yield ammonium sulfate. The acrylamide crystallized on cooling, leaving ammonium sulfate, which had to be disposed of in some way. The second method of purification involved ion exclusion (68), which utilized a sulfonic acid ion-exchange resin and produced a dilute solution of acrylamide in water. A dilute sulfuric acid waste stream was again produced, and, in either case, the waste stream represented a... 

Important side reactions are the formation of ether and addition of alcohol to the acrylate to give 3-alkoxypropionates. In addition to high raw material costs, this route is unattractive because of large amounts of sulfuric acid—ammonium sulfate wastes. 

When coal is coked at a temperature of approximately 1000°C, about 70—75% of the product is coke. Nearly 20% of the product is a light gas, mostiy methane and hydrogen, that typically is used as fuel to heat the ovens. Coal tars amount to about 4% of the product and light oil or naphtha is about 1%. Ammonia is recovered in an amount equal to about 0.3% of the feed coal. The ammonia is usually converted to ammonium sulfate and sold as a fertilizer. Littie or no ammonia [7664-41-7] is produced inlow temperature carbonization (3). 

Ammonium Sulfate. Historically ammonium sulfate was important as a fertilizer. However, since the introduction of ammonium nitrate and urea, the relative importance of ammonium sulfate worldwide has steadily decreased. In the year ended June 30, 1990, ammonium sulfate furnished only about 4% of the fertilizer nitrogen used in the United States (Fig. 3) and worldwide (Fig. 6). 

Essentially all the ammonium sulfate fertilizer used in the United States is by-product material. By-product from the acid scmbbing of coke oven gas is one source. A larger source is as by-product ammonium sulfate solution from the production of caprolactam (qv) and acrylonitrile, (qv) which are synthetic fiber intermediates. A third but lesser source is from the ammoniation of spent sulfuric acid from other processes. In the recovery of by-product crystals from each of these sources, the crystallization usually is carried out in steam-heated sa turator—crystallizers. Characteristically, crystallizer product is of a particle size about 90% finer than 16 mesh (ca 1 mm dia), which is too small for satisfactory dry blending with granular fertilizer materials. Crystals of this size are suitable, however, as a feed material to mixed fertilizer granulation plants, and this is the main fertilizer outlet for by-product ammonium sulfate. 

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