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United States sulfur

Vincent Du Vigneaud United States sulfur compounds of biological importance, synthesis of polypeptide hormone... [Pg.409]

We begin our discussion with what is by far the largest volume chemical produced in the United States sulfuric acid. It is normally manufactured at about twice the amount of any other chemical and is a leading economic indicator of the strength of many industrialized nations. Since about 80% of all sulfuric acid is made by the contact process which involves oxidation of sulfur, we will examine this raw material in detail. The average per capita consumption of sulfur in the United States is a staggering 135 Ib/yr. [Pg.28]

In the United States, sulfur is found mainly in Texas and Louisiana, where it is obtained by the Frasch process that can be illustrated as shown in Figure 15.1. This process makes use of three concentric pipes. The deposits are found several hundred feet below the surface and are heated to melting by sending water that has been heated under pressure to 170 °C down the outside pipe. Compressed air is forced down the center pipe, and the molten sulfur is then forced by pressure up the third pipe along with water and air. [Pg.342]

In 1996, the total nameplate capacity for sulfuric acid in Canada was 5,681 kilotons and in the United States it was 36,306 kilotons. In 1993, the total global production of sulfuric acid was close to 135.3 megatons. Some growth is expected in the Middle East and North Africa. In Canada and the United States, sulfuric acid is transported primarily by rail and truck. Long-distance transport of sulfuric acid from smelters in remote locations makes freight costs extremely high. [Pg.773]

However, such a level can still be considered too high for vehicles having 3-way catalytic converters. In fact, results observed in the United States (Benson et al., 1991) and given in Figure 5.20 show that exhaust pollutant emissions, carbon monoxide, hydrocarbons and nitrogen oxides, increase from 10 to 15% when the sulfur level passes from 50 ppm to about 450 ppm. This is explained by an inhibiting action of sulfur on the catalyst though... [Pg.252]

At this point in time, the total sulfur content of crudes was not taken into consideration, since most of them were produced and refined in the United-States and contained less than 1%, and only the gasoline coming from corrosive crudes needed sweetening (elimination of thiols) for them to meet the specifications then in force. Today all crudes containing more than one per cent sulfur are said to be corrosive . [Pg.322]

The combination of sulfuric acid addition to propene followed by hydrolysis of the resulting isopropyl hydrogen sulfate is the major method by which over 10 lb of isopropyl alcohol is prepared each year m the United States... [Pg.246]

From cumene Almost all the phenol produced in the United States is prepared by this method Oxi dation of cumene takes place at the benzylic posi tion to give a hydroperoxide On treatment with dilute sulfuric acid this hydroperoxide is converted to phenol and acetone... [Pg.1000]

BATF permits no more acetic acid than 1.4 g/L in ted table and 1.2 g/L in white and dessert wines, Califotnia and the European Union slightly less. California requites a minimum fixed acidity as tartaric of 4.0 g/L for ted table, 3.0 g/L for white table, and 2.5 g/L for dessert wines. Califotnia also requites a minimum extract in dry wines of 18 g/L for ted and 17 g/L for white, but other states generally do not specify a minimum. In the United States, maximum total sulfur dioxide is 350 mg/L. Fat less is usually used today. European maxima ate lower for dry wines and higher for sweet table wines. [Pg.376]

Acetic acid has a place in organic processes comparable to sulfuric acid in the mineral chemical industries and its movements mirror the industry. Growth of synthetic acetic acid production in the United States was gready affected by the dislocations in fuel resources of the 1970s. The growth rate for 1988 was 1.5%. [Pg.69]

Selection of pollution control methods is generally based on the need to control ambient air quaUty in order to achieve compliance with standards for critetia pollutants, or, in the case of nonregulated contaminants, to protect human health and vegetation. There are three elements to a pollution problem a source, a receptor affected by the pollutants, and the transport of pollutants from source to receptor. Modification or elimination of any one of these elements can change the nature of a pollution problem. For instance, tall stacks which disperse effluent modify the transport of pollutants and can thus reduce nearby SO2 deposition from sulfur-containing fossil fuel combustion. Although better dispersion aloft can solve a local problem, if done from numerous sources it can unfortunately cause a regional one, such as the acid rain now evident in the northeastern United States and Canada (see Atmospheric models). References 3—15 discuss atmospheric dilution as a control measure. The better approach, however, is to control emissions at the source. [Pg.384]

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. [Pg.221]

Cost Fa.ctors, The dehvered costs of the phosphate rock and sulfuric acid raw materials often account for more than 90% of the cost of producing NSP, thus the production cost varies considerably with plant location. Because the rock is richer in P2O5 than is the low analysis NSP product, NSP need not be produced near the phosphate mine. However, deUvery of sulfuric acid and shipment of product to market are important cost factors. Most United States NSP plants have been located east of the Mississippi river, with concentration in the southeastern and extreme southern parts of the country where the largest use of the product has occurred. Production and use of the product also has been high in California. [Pg.224]

Production of nitric phosphates is not expected to expand rapidly ia the near future because the primary phosphate exporters, especially ia North Africa and the United States, have moved to ship upgraded materials, wet-process acid, and ammonium phosphates, ia preference to phosphate rock. The abundant supply of these materials should keep suppHers ia a strong competitive position for at least the short-range future. Moreover, the developiag countries, where nitric phosphates would seem to be appealing for most crops except rice, have already strongly committed to production of urea, a material that blends compatibly with sulfur-based phosphates but not with nitrates. [Pg.231]

Nonetheless, production and use of nitric phosphates ia Europe are continuing to grow. In general, nitric phosphate processes are somewhat more compHcated than sulfur-based processes and requite higher investment. In the past, several attempts have been made to estabHsh commercial acceptance of this type process ia the United States, but plant operations have been relatively short Hved because of low sulfur prices and resultant competition from sulfur-based processes. [Pg.231]

Resources of Sulfur. In most of the technologies employed to convert phosphate rock to phosphate fertilizer, sulfur, in the form of sulfuric acid, is vital. Treatment of rock with sulfuric acid is the procedure for producing ordinary superphosphate fertilizer, and treatment of rock using a higher proportion of sulfuric acid is the first step in the production of phosphoric acid, a production intermediate for most other phosphate fertilizers. Over 1.8 tons of sulfur is consumed by the world fertilizer industry for each ton of fertilizer phosphoms produced, ie, 0.8 t of sulfur for each ton of total 13.7 X 10 t of sulfur consumed in the United States for all purposes in 1991, 60% was for the production of phosphate fertilizers (109). Worldwide the percentage was probably even higher. [Pg.245]

Sulfur hexafluoride was first prepared in 1902 (1). The discovery in 1937 that its dielectric strength is much higher than that of air (2) led to its use as an insulating material for cables, capacitors (3), and transformers (4) (see Insulation,electric). Sulfur hexafluoride has been commercially available as AccuDri, SF (AUiedSignal Inc.) since 1948. It is also produced by Air Products and Chemicals in the United States and by others in Germany, Italy, Japan, and Russia. [Pg.240]

In the United States there was Httie interest in solvent processing of coals. A method to reduce the sulfur content of coal extracts by beating with sodium hydroxide and zinc oxide was, however, patented in 1940 (116). In the 1960s the technical feasibiHty of a coal deashing process was studied (117),... [Pg.89]

Large-scale recovery of light oil was commercialized in England, Germany, and the United States toward the end of the nineteenth century (151). Industrial coal-tar production dates from the earliest operation of coal-gas faciUties. The principal bulk commodities derived from coal tar are wood-preserving oils, road tars, industrial pitches, and coke. Naphthalene is obtained from tar oils by crystallization, tar acids are derived by extraction of tar oils with caustic, and tar bases by extraction with sulfuric acid. Coal tars generally contain less than 1% benzene and toluene, and may contain up to 1% xylene. The total U.S. production of BTX from coke-oven operations is insignificant compared to petroleum product consumptions. [Pg.96]

Immobile hydrocarbon sources requite refining processes involving hydrogenation. Additional hydrogen is also requited to eliminate sources of sulfur and nitrogen oxides that would be emitted to the environment. Resources can be classified as mostiy consumed, proven but stiU in the ground, and yet to be discovered. A reasonable estimate for the proven reserves for cmde oil is estimated at 140 x 10 t (1.0 x 10 bbl) (4). In 1950 the United States proven reserves were 32% of the world s reserve. In 1975 this percentage had decreased to 5%, and by 1993 it was down to 2.5%. Since 1950 the dominance of... [Pg.364]

Decomposition of Metal Chlorides by Acids. Two commercial processes employing the acidic decomposition of metal chlorides are the salt—sulfuric acid process and the Hargreaves process. Although these processes are declining in importance, they are used mainly because of the industrial demand for salt cake [7757-82-6] by the paper (qv) and glass (qv) industries. In the United States, however, Httle HCl is produced this way. [Pg.445]

Plant investment and maintenance costs are relatively high for a new iodine plant in the United States or in Japan because of the deep weUs required for brine production and disposal as weU as the corrosive nature of the plant streams. The principal materials cost is for chlorine and for sulfur dioxide, although in the United States the additives used for the brines, such as scale inhibitors and bactericides, also have a considerable influence on costs. [Pg.364]

Uranium ores are leached with dilute sulfuric acid or an alkaline carbonate [3812-32-6] solution. Hexavalent uranium forms anionic complexes, such as uranyl sulfate [56959-61-6], U02(S0 3, which are more selectively adsorbed by strong base anion exchangers than are other anions in the leach Hquors. Sulfate complexes are eluted with an acidified NaCl or ammonium nitrate [6484-52-2], NH NO, solution. Carbonate complexes are eluted with a neutral brine solution. Uranium is precipitated from the eluent and shipped to other locations for enrichment. Columnar recovery systems were popular in South Africa and Canada. Continuous resin-in-pulp (RIP) systems gained popularity in the United States since they eliminated a difficult and cosdy ore particle/leach hquor separation step. [Pg.387]


See other pages where United States sulfur is mentioned: [Pg.274]    [Pg.1570]    [Pg.11]    [Pg.1162]    [Pg.261]    [Pg.146]    [Pg.520]    [Pg.274]    [Pg.1570]    [Pg.11]    [Pg.1162]    [Pg.261]    [Pg.146]    [Pg.520]    [Pg.253]    [Pg.264]    [Pg.372]    [Pg.374]    [Pg.377]    [Pg.385]    [Pg.504]    [Pg.162]    [Pg.169]    [Pg.213]    [Pg.234]    [Pg.242]    [Pg.3]    [Pg.78]    [Pg.172]    [Pg.441]    [Pg.424]    [Pg.516]    [Pg.363]    [Pg.387]   
See also in sourсe #XX -- [ Pg.3 , Pg.564 , Pg.565 ]




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