Major Uses of Sulfuric Acid

A second major use of sulfuric acid of commerce is in reactions with bases. In laboratory use it is diluted to a much lower concentration and can be used as a standard acid. A typical problem would be the titration of a base solution of unknown concentration using a sulfuric acid solution of known concentration. For example, What is the concentration of a sodium hydroxide solution if 25.43 ml of the NaOH solution just reacts with 18.51 ml of 0.1250 M HiSOt (to produce a neutral solution) ... 

A major use of sulfuric acid is as catalyst for petroleum refining and polymer manufacture, Chapter 5. The acid becomes contaminated with water, hydrocarbons and other compounds during this use. It is regenerated by ... 

Sulfuric acid has many uses but one of the largest uses is for fertilizer manufacture. Primary nutrients for plants are nitrogen, phosphorus and potassium. The major use of sulfuric acid in fertilizer manufacture is in the production of phosphoric acid, which in turn is used to produce phosphorus-containing fertilizers. 

A major use of sulfuric acid is in the manufacture of phosphoric acid (H3PO4), also known as orthophosphoric acid. The principle use of phosphoric acid is to make fertilizers. In the United States, phosphate rock ore is mined by six companies at 12 mines and upgraded to 28 million metric tons [8]. Most of the mining is done in Florida and North Carolina. China is the leading producer of phosphate rock with 72 milhon metric tons of the 191 million metric tons manufactured worldwide. 

Sulfate solubility properties are the basis for other industrial uses of sulfuric acid. One example is in the metallurgy of titanium. One of the major ores of titanium is FeTi03, which is treated with sulfuric acid to separate titanium from iron ... 

The application of solvent extraction to copper recovery has been a major growth area since the last review of this series.11,13 Almost 30% of world production in 2000 involved the use of sulfuric acid heap leaching, solvent extraction, and electrowinning, far exceeding earlier predictions.136... 

About 60 percent of the sulfuric acid in turn is used for agricultural purposes, mainly in phosphoric acid production, and intermediate in fertilizer manufacture. Another important use of sulfuric acid is in petroleum refining. Chemical uses, including plastics, paper and paint, account for 8 percent of sulfur production, sulfuric acid again being a major outlet. Ferrous and non-ferrous metal production consumes 8 percent and miscellaneous uses add up to 18 percent. 

All cooling water treatment programs, whether designed in-house or via a water treatment service company, continue to focus on the minimization of hard water crystalline scales and sludges in the system as a major criteria for success. Program techniques employed are either pretreatment processes, such as lime-soda softening or ion exchange, the use of sulfuric acid or polymer-based chemicals that operate in an alkaline environment, or combinations of some or all of these processes. 

The major use of sulfur is in the production of sulfuric acid. This is probably the most important industrial chemical, and the quantity of it produced by a country has been linked with the economic stability of the country. In excess of 150 million tonnes of sulfuric acid are produced worldwide each year. It is used mainly as the raw material for the production of many substances (Figure 12.6). 

Uses of sulfuric acid. It is not feasible here to do more than briefly mention the major uses of this acid. Of these, the use of dilute sulfuric... 

Chemetics has developed a process for treating spent alkylation sulfuric acid with nitric acid to produce a sulfuric acid that can be used to acidulate phosphate rock, the major use for sulfuric acid. The organic contaminants are converted to carbon particles that are removed with the gypsum on filtration of the phosphoric acid. Special alloys are used in the fabrication of the acid reactor. Topsoe developed and, by the year 2005 had built, more than 45 Wet Sulfuric Acid (WSA) process units. This process is especially suited for... 

The major use of sulfur today is in the production of sulfuric acid, and approximately two-thirds of the sulfur produced is used in this way. Over half of the sulfuric acid... 

The use of sulfuric acid in automobile batteries, however, does not account for its production in such vast quantities. The largest single use for sulfuric acid is fertilizers, especially a sulfuric-acid/phosphate-containing-rock mixture called superphosphate. Because phosphorus is a major mineral nutrient needed by plants and because phosphorus is a major component of bones, bone meal was once a commonly used fertilizer. Today, however, phosphate rock, treated with sulfuric acid to become more soluble, can be used, too. 

The other major use of nitric acid is in organic nitration. Nitration using mixtures of sulfuric and nitric acid is the first step in the synthesis of amino-and nitro-compounds such as aniline and trinitrotoluene (TNT). Many important dyes and pharmaceuticals are ultimately derived from these reactions. However, their quantities are quite small. Polyurethane polymers are also ultimately derived from nitrated toluene and benzene and this use accounts for 5—10% of nitric acid end uses. 

On the other hand, Evans and Lockhart126 reported that treating 105 (R -R6 = H R7 = OMe R8 = R9 = H) with PPA gave 18 (R1 = H R2 = OMe) as the major product and only some l-benzazepin-2-one. The use of sulfuric acid resulted in tarry products. The 2-tetralone oxime (118, R1 = R2 = R3 = Me R4 = R5 = H) was reported126 to give 24% yield of 86 (R -R4 = Me Rs = R6 = H). Since then, Conley and Lange127 have studied 2-tetralone oximes and shown another mechanism by which the products of Beckmann rearrangement were formed. When the oxime 118 (R1 = Me R2-R6 = H) was treated with phosphorus penta-chloride, a 93-96% yield of the nitrile 119 was obtained. The nitrile could... 

A major use of phosphoric acid is fertiUzer production. In the past, phosphorus-containing materials such as fish, bones, and bat guano were used as fertiUzer. Sulfuric acid decomposes bones to make phosphorus compounds that are more readily taken np by plants. Today many different phosphorus compounds have been developed specifically as fertilizers for various types of plants. 

This involves heating rubber with sulfur to induce cross-linkage between the long hydrocarbon chains of which rubber is composed, and results in a product with superior mechanical properties. However, the major uses of sulfur are in the heavy chemical industry. Nearly 90% of all the sulfur used goes to the production of sulfuric acid. 

Sulfur (qv) is among the most widely used chemicals and often considered to be one of the four basic raw materials of the chemical iadustry. In 1993, worldwide production of sulfur reached 55 million metric tons (1). Production of sulfuric acid consumes the vast majority (- 90%) of sulfur (2) (see Sulfuric acid and sulfur trioxide). This acid is a steppiag stone ia the production of other sulfur-containing compounds, most notably ammonium sulfate fertilizer which accounts for 60% of the total worldwide sulfur consumption (2) (see Ammonium compounds Fertilizers). 

Anhydrous sulfuric acid is a dense, viscous liquid which is readily miscible wilh water in all proportions the reaction is extremely exothermic ( 880kJmol at infinite dilution) and can result in explosive spattering of the mixture if the water is added to the acid it is therefore important always to use the reverse order and add the acid to the water, slowly and with stirring. The large-scale preparation of sulfuric acid is a major industr) in most countries and is described in the preceding Panel. 

The major discharges from sulfuric acid alkylation are the spent caustics from the neutralization of hydrocarbon streams leaving the alkylation reactor. These wastewaters contain dissolved and suspended solids, sulfides, oils, and other contaminants. Water drawn off from the overhead accumulators contains varying amounts of oil, sulfides, and other contaminants, but is not a major source of waste. Most refineries process the waste sulfuric acid stream from the reactor to recover clean acids, use it to neutralize other waste streams, or sell it. 

Fig. 8.5 shows the U.S. production of ethylene, propylene, and butadiene over the years. Ethylene has shown a good, steady increase for many years since the 1950s, as it has replaced ethanol as the major C2 raw material and is now used in nearly half of all organic polymers and chemicals produced by volume. Some would argue that it should be used in place of sulfuric acid as the main economic indicator of the chemical industry. Certainly for organic chemicals it has top billing. Propylene shows a similar but lower trend. Although the official production of propylene is usually about half that of ethylene, it is probably near ethylene if captive refmeiy-made... 

The results of Ikawa and Niemann,78 who used 79% sulfuric acid for 15 minutes at 100°, of Bath,220 who used 90% sulfuric acid for 5 minutes at 100°, and others221 indicated that, when so treated, hexoses, 6-deoxyhexoses, and D-xylose give rise to the appropriate 2-furalde-hyde as the principal ultraviolet-absorbing product, but that other pentoses, as well as hexuronic acids, afford mixtures of compounds in which 2-furaldehyde is the major, but not the sole, product. 

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