Hydrogen from sulfuric acid

In metallurgy, hydrogen sulfide is used to precipitate copper sulfide from nickel—copper-containing ore leach solutions in Alberta, Canada, or to precipitate nickel and cobalt sulfides from sulfuric acid leaching oflaterite ores in Moa Bay, Cuba (120) (see Metallurgy, extractive metallurgy). 

It resembles tetracyanoethylene in that it adds reagents such as hydrogen (31), sulfurous acid (31), and tetrahydrofuran (32) to the ends of the conjugated system of carbon atoms suffers displacement of one or two cyano groups by nucleophilic reagents such as amines (33) or sodiomalononittile (34) forms TT-complexes with aromatic compounds (35) and takes an electron from iodide ion, copper, or tertiary amines to form an anion radical (35,36). The anion radical has been isolated as salts of the formula (TCNQ) where is a metal or ammonium cation, and n = 1, 1.5, or 2. Some of these salts have... 

Aminoethyl hydrogen sulfate (sulfuric acid mono-2-aminoethyI ester) [926-39-6] M 141.1, m 285-287 (chars at 275 ). Crystd from water or dissolved in water and EtOH added. 

Climax A process for making sodium sulfate from sulfuric acid and sodium chloride. Sulfuric acid is sprayed onto a hot fluidized bed of sodium chloride. The products are granular sodium sulfate and hydrogen chloride gas. Invented in 1967 by C. K. Curtis later developed and commercialized by C. W. Cannon at the Climax Chemical Company at Midland, NM, in the 1970s. Midland was a favorable location because of the proximity of mineral salt and sulfur from petroleum and the availability of cheap transport of the product from the site. French Patent 1,549,938. 

Co-precipitation of Re S with platinum sulfide from cone, hydrochloric acid solutions of microamounts of technetium and rhenium is suitable for the separation of technetium from rhenium , since technetium is only slightly co-precipitat-ed under these conditions (Fig. 7). At concentrations of 9 M HCl and above, virtually no technetium is co-precipitated with platinum sulfide at 90 °C, whereas rhenium is removed quantitatively even up to 10 M HCl. The reduction of pertechnetate at high chloride concentration may be the reason for this different behavior, because complete co-precipitation of technetiiun from sulfuric acid solutions up to 12 M has been observed. However, the separation of weighable amounts of technetium from rhenium by precipitation with hydrogen sulfide in a medium of 9-10 M HCl is not quantitative, since several percent of technetiiun coprecipitate with rhenium and measurable amounts of rhenium remain in solu-tion . Multiple reprecipitation of Re S is therefore necessary. 

This is the reverse of acid-catalyzed hydration of alkenes discussed previously (Section 10-3E) and goes to completion if the alkene is allowed to distill out of the reaction mixture as it is formed. One mechanism of dehydration involves proton transfer from sulfuric acid to the alcohol, followed by an E2 reaction of hydrogen sulfate ion or water with the oxonium salt of the alcohol ... 

In the Sulfur Cycle, hydrogen is produced in a low temperature electrochemical step, wherein sulfuric acid and hydrogen are produced from sulfurous acid, i.e.,... 

Toxic chemicals tliat could potentially cause a major problem if accidentally released into tlie atmosphere include clilorine, hydrogen fluoride, hydrogen chloride, ammonia, chloropicrin, gasoline lead additives, vinyl cliloridc. and benzene. Hiis chapter addresses the process application of some chemicals from the foregoing list, as well as some others that are considered to be highly toxic hydrogen cyanide, sulfuric acid, and etliylene. Process considerations, physical and chemical properties, healtli effects, and metliods of manufacture of tliese chemicals are discussed in conjunction with potential causes of release. 

Tin is reactive enough to displace hydrogen from dilute acids, but it does not tarnish in moist air. It reacts with warm hydrochloric acid to produce stannous chloride, SnCb, and hydrogen, and with hot concentrated sulfuric acid to produce stannous sulfate, SnSO, and sulfur dioxide, the equations for these reactions being... 

Petrolatum is manufactured from the semisolid residue that remains after the steam or vacuum distillation of petroleum. This residue is dewaxed and/or blended with stock from other sources, along with lighter fractions, to give a product with the desired consistency. Final purification is performed by a combination of high-pressure hydrogenation or sulfuric acid treatment followed by filtration through adsorbents. A suitable antioxidant may be added. 

Several molecules are held together to become an indivisible molecule because the diatomic radical of sulfuric acid rearranges itself in such a way that one half of it takes the place of the typical hydrogen. This is by far the most common case it is exactly the same process which causes the formation of sulfuric acid hydrate from sulfuric acid anhydride and water, and the formation of Nordhauser s oil of vitriol from sulfuric acid anhydride and hydrate. For instance ... 

The cathode reaction is presented by hydrogen evolution from sulfuric acid. In this case, graphite may be used as electrode material. 

Commercial tetralin contains naphthalene as the principal impurity and this interferes with the preparation of tetralin-1-hydroperoxide or with use of the hydrocarbon as hydrogen donor in hydrogen-transfer reactions. An early purification procedure is uninviting fractionation extraction in turn with mercury (to remove sulfur impurities), with mercuric acetate solution (to remove olefins), and with sulfuric acid fractionation. More recently Bass sulfonated the crude hydrocarbon with coned, sulfuric acid and added ammonium chloride to precipitate ammonium tetralin-6-sulfonate. The salt was crystallized until pure and hydrolyzed by steam distillation from sulfuric acid solution. Distillation from sodium gave material showing no ultraviolet bands characteristic of naphthalene. 

The dehydration reaction proceeds via a carbocation mechanism. The three step mechanism starts with the protonation of the alcohol oxygen with a hydrogen ion from sulfuric acid by a Lewis acid-Lewis base reaction. Water departs in the second step leaving a carbocation intermediate. In the final step, a hydrogen ion leaves the adjacent carbon and the double bond forms. 

One possibility of introducing the concept is the production of gaseous hydrogen chloride from sulfuric acid and common table salt (see E7.8) and subsequent reaction of the produced gas with water to form hydrochloric acid (see E7.9). In the first part, H2S04 molecules donate protons to Cl- ions from sodium chloride crystals to form HC1 molecules and [fSC)4 ions ... 

All of these data may be reconciled with the formation of substituted allylic (alkenyl) carbonium ions. Structures of this type can be derived from any substituted olefin by removal of a hydride ion from a carbon atom adjacent to the double bond (a-hydrogen). Since an olefin may be derived by proton removal from an alkyl carbonium ion, a substituted alkenyl ion may be derived from any alkyl carbonium ion precursor containing at least four carbon atoms and hence the spectra of their solutions should be very similar. Sulfur dioxide evolution from sulfuric acid solutions of olefins would accompany the formation of the alkenyl... 

Most methyl methacrylate (MMA) is made by the acetone cyanohydrin process. Developed in the 1930s for the production of MMA from acetone, hydrogen cyanide, sulfuric acid, and methanol, it has been improved over the years, but problems inherent in the basic process persist. For example, production of large quantities of ammonium bisulfate by-product and sulfuric acid sludge, as well as difficulty in obtaining low cost sources of... 

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