Sulfuric acid production from sulfur

Earlier animal work showed similar results in terms of urinary acid production from dietary precursors that could be converted into acid before excretion. However, most investigators used salts rather than foods containing the anion or its precursor. The addition of acid, in the form of hydrochloric, sulfuric, or ammonium chloride, acid phosphate salts, or ascorbate resulted in enhanced urinary acidity and concomitant calcium excretion. For example, in the detailed study of bone salt metabolism, Barzel and Jowsey (19) showed that the rat fed supplementary ammonium chloride subsequently lost more calcium, and developed markedly demineralized fat-free bone mass. 

Ill - Alabama, Arkansas, Louisiana, Mississippi, New Mexico, and Texas. IV - Colorado, Idaho, Montana, Utah, and Wyoming. V -Alaska, Arizona, California, Hawaii, Nevada, Oregon, and Washington.] The justification is that for the next decade at least oil and gas are likely to continue as the primary sources of domestic recovered sulfur. Second, the inclusion of Arizona and Nevada in PAD district V roughly corresponds with the present market for acid production from copper smelters. Third, as the districts are established on the basis of an aggregation of states, data compilation is simplified. And fourth, as the districts have been defined ja priori they were not based on present expository requirements. 

TABLE 25.6 Sulfuric Acid Production from Pyrites and Other Forms (Million Tons 100% H2S04)... 

Since water is formed in the sulfonation reaction and dilutes the sulfuric acid, an appreciable excess of the add is dways necessary in order that its concentration be maintained sufficiendy high throughout the reaction. When sulfonation is done with oleum, usually only the SO3 is used up, so that at the end of the reaction a large excess of sulfuric acid remains. The separation of the sulfonic acid product from the excess sulfuric acid is simplest in the case of sulfonic acid derivatives of anunes. These compounds, if they contain an equal number of sulfo and amino groups, are generally so dilficuldy soluble in water, and particularly in dilute sulfuric acid, that they are almost completely precipitated on dilution of the sulfonation mixture, and need only to be filtered off and washed. 

Sulfuric acid production from H2S and SO2 with V2O5 (s) as the catalyst ... 

One commercial method to obtain nitric acid concentrations above 68% uses concentrated sulfuric acid to dehydrate the azeotropic composition. Hot nitric acid vapor is passed upward against concentrated sulfuric acid, which moved downward (countercurrent) in a tower packed with chemical stoneware to obtain 90+%HNO3 and a diluted sulfuric acid stream (Fig. 11.6). If this process is practiced on only a small scale, the sulfuric acid may be reconcentrated by addition of oleum, and a portion of the buildup of sulfuric acid in this circuit may be used to make up a commercial nitrating mixture with some of the fuming nitric acid made. Larger scale operation requires the use of a sulfuric acid boiler and a large heat input to reconcentrate the dehydration acid. There is also a noticeable sulfate contamination of the nitric acid product from this process. 

However, this paper is primarily concerned with sulfuric acid production from copper smelters where most of the sulfur dioxide is in a gas stream which varies widely and frequently, both in gas volume and in sulfur dioxide concentration. This gas stream presents a real challenge... 

More sulfuric acid is produced than any other chemical in the world. In Western Europe in 1997 over 19 million tonnes were produced, the total production worldwide being estimated at around 150 million tonnes. About half of this output is produced in North America, Western Europe, and Japan. The world voluntary and involuntary sulfuric acid production from 2006 to 2015 is shown in Figs. 1.3 and 1.4. 

Figure 11.10. Sulfuric Acid Production From Gypsum [16].

Phosphoric acid and phosphate salts are produced either by oxidation of elemental phosphorous or by extraction of the phosphate mineral Ca3(P04)2 (apatite) with sulfuric acid. Production from elemental phosphorous is energetically more demanding and therefore capacities are increasingly shifting towards the extraction process. However, the production of food grade phosphoric acid from the natural mineral apatite requires additional separation and purification steps to remove heavy metals (such as e.g., Cu or As) from the crude phosphoric acid. Precipitation techniques and countercurrent extraction with organic solvents, such as n-butanol or diisopropyl ether, are applied for this purpose. 

When benzene is prepared from coal tar it is contaminated thiophene from which it cannot be separated by distillation because of very similar boiling points Shaking a mixture of benzene and thiophene with sulfuric acid causes sulfonation of the thiophene ring but leaves benzene untouched The sulfonation product of thiophene dissolves m the sulfuric acid layer from which the benzene layer is separated the benzene layer is then washed with water and distilled Give the structure of the sulfonation product of thiophene... 

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... 

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. 

The products of reaction are pumped to a filter press for separation into a sodium sulfate solution and a filter cake having a low moisture content. The filter cake is then ready to be processed for the recovery of lead. The filtrate from the process contains an excess of sodium carbonate, and can be neutralized using the sulfuric acid drained from the batteries. 

To overcome these difficulties, drilling fluids are treated with a variety of mud lubricants available from various suppHers. They are mostly general-purpose, low toxicity, nonfluorescent types that are blends of several anionic or nonionic surfactants and products such as glycols and glycerols, fatty acid esters, synthetic hydrocarbons, and vegetable oil derivatives. Extreme pressure lubricants containing sulfurized or sulfonated derivatives of natural fatty acid products or petroleum-base hydrocarbons can be quite toxic to marine life and are rarely used for environmental reasons. Diesel and mineral oils were once used as lubricants at levels of 3 to 10 vol % but this practice has been curtailed significantly for environmental reasons. 

Additional phosphonic acid is derived from by-product streams. In the manufacture of acid chlorides from carboxyUc acids and PCl, phosphonic acid or pyrophosphonic acid is produced, frequentiy with copious quantities of yellow polymeric LOOP. Such mixtures slowly evolve phosphine, particularly on heating, and formerly were a disposal problem. However, purification of this cmde mixture affords commercial phosphonic acid. By-product acid is also derived from the precipitate of calcium salts in the manufacture of phosphinic acid. As a consequence of the treatments of the salt with sulfuric acid, carbonate is Hberated as CO2 and phosphonic acid goes into solution. 

Ammonia is consumed in the manufacture of ammonium phosphates and ammonium sulfate by reaction with phosphoric acid and sulfuric acid, respectively. The phosphates may contain ortho- and polyphosphate values. Ammonium sulfate is also a by-product from other ammonia-using industries such as caprolactam (qv) and hydrogen cyanide (see Cyanides). 

Recovering ammonia as a by-product from other processes accounted for less than 1% of the total U.S. ammonia production in 1987. The principal source of by-product ammonia is from the coking of coal. In the coking operation, about 15—20% of the nitrogen present in the coal is Hberated as ammonia and is recovered from the coke oven gas as ammonium sulfate, ammonia Hquor, and ammonium phosphates. The recovery product depends on the scmbbing medium employed, sulfuric acid, milk of lime, and phosphoric acid, respectively. Ammonium sulfate recovery by the so-called semidirect process, is most widely employed. 

Thermal decomposition of spent acids, eg, sulfuric acid, is required as an intermediate step at temperatures sufficientiy high to completely consume the organic contaminants by combustion temperatures above 1000°C are required. Concentrated acid can be made from the sulfur oxides. Spent acid is sprayed into a vertical combustion chamber, where the energy required to heat and vaporize the feed and support these endothermic reactions is suppHed by complete combustion of fuel oil plus added sulfur, if further acid production is desired. High feed rates of up to 30 t/d of uniform spent acid droplets are attained with a single rotary atomizer and decomposition rates of ca 400 t/d are possible (98). 

Although tetrafluorosilane can be readily produced by the action of hydrogen fluoride on sihca, its production is a by-product of HF production by the reaction of fluorospar and sulfuric acid and as a by-product from phosphate fertilizer production by the treatment of fluoroapatite with sulfuric acid (171). The most significant U.S. production is by IMC-Agrico at Uncle Sam, Louisiana. 

Fig. 1. Sulfonated and sulfated acid products viscosities after 98% conversions at varying temperatures where the vertical line indicates the maximum temperature for batch sulfonation using SO to minimi2e color deterioration lines A—C represent branched C 2 alkyl ben2ene (BAB) sulfonic acid from SO, oleum (settied), and oleum (whole mixture), respectively lines D and E, lauryl alcohol 3-ethoxylate sulfuric ester (SO ) and lauryl alcohol sulfuric ester...

Sulfuric acid is the most commonly used reagent for the recovery of uranium from ores, and vanadium is often recovered as a coproduct. The sulfuric acid used is either the by-product sulfuric acid produced at smelters or sulfuric acid produced from elemental sulfur. 

Production from Oleum. Production of SO2 from oleum was developed at Stauffer Chemical Company and is used commercially by Rhc ne-Poulenc to produce Hquid sulfur dioxide. It can be kitegrated with an existing oleum operation or with a concentrated sulfuric acid-consuming operation. 

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