Rhenium sulfide oxidizes

Alternate method Rhenium sulfides, oxides or rhenium metal are dissolved in HNO3. The solution is evaporated and diluted with ammonia. Recrystallization is required May be used to prepare pure rhenium (see p. 1476). 

The following metal compounds are used for the preparation of the catalysts oxides, metal carbonyls, halides, alkyl and allyl complexes, as well as molybdenum, tungsten, and rhenium sulfides. Oxides of iridium, osmium, ruthenium, rhodium, niobium, tantalum, lanthanum, tellurium, and tin are effective promoters, although their catalytic activity is considerably lower. Oxides of aluminum, silicon, titanium, manganese, zirconium as well as silicates and phosphates of these elements are utilized as supports. Also, mixtures of oxides are used. The best supports are those of alumina oxide and silica. 

Rhenium oxides have been studied as catalyst materials in oxidation reactions of sulfur dioxide to sulfur trioxide, sulfite to sulfate, and nitrite to nitrate. There has been no commercial development in this area. These compounds have also been used as catalysts for reductions, but appear not to have exceptional properties. Rhenium sulfide catalysts have been used for hydrogenations of organic compounds, including benzene and styrene, and for dehydrogenation of alcohols to give aldehydes (qv) and ketones (qv). The significant property of these catalyst systems is that they are not poisoned by sulfur compounds. 

Palladium and platinum (5—10 wt % on activated carbon) can be used with a variety of solvents as can copper carbonate on siHca and 60 wt % nickel on kieselguhr. The same is tme of nonsupported catalysts copper chromite, rhenium (VII) sulfide, rhenium (VI) oxide, and any of the Raney catalysts, copper, iron, or nickel. 

Rhenium halides, 21 699-700 Rhenium hydrides, 21 700 Rhenium imports, U.S., 21 688t Rhenium oxides, 21 699 Rhenium powder, 21 688, 689, 690, 693 specifications for, 21 694t Rhenium sulfides, 21 699... 

ReaC>7 Rhenium(VII) oxide, 3 188 Re3S7 Rhenium(VII) sulfide, 1 177... 

Solid catalysts for the metathesis reaction are mainly transition metal oxides, carbonyls, or sulfides deposited on high surface area supports (oxides and phosphates). After activation, a wide variety of solid catalysts is effective, for the metathesis of alkenes. Table I (1, 34 38) gives a survey of the more efficient catalysts which have been reported to convert propene into ethene and linear butenes. The most active ones contain rhenium, molybdenum, or tungsten. An outstanding catalyst is rhenium oxide on alumina, which is active under very mild conditions, viz. room temperature and atmospheric pressure, yielding exclusively the primary metathesis products. 

Molybdenum metalworking, 17 10-11 Molybdenum mill products, 17 9-10 Molybdenum-nickel alloys, 17 102 Molybdenum ore, U.S. exports of, 17 3t Molybdenum oxidation states, 17 20 Molybdenum oxides, 17 38 Molybdenum pentachloride, 17 23 Molybdenum-rhenium alloys, 17 15 Molybdenum sulfide, poisons in representative reactions, 5 258t Molybdenum-sulfur complexes, molecular, 17 37... 

Although all of the above elements catalyze hydrogenation, only platinum, palladium, rhodium, ruthenium and nickel are currently used. In addition some other elements and compounds were found useful for catalytic hydrogenation copper (to a very limited extent), oxides of copper and zinc combined with chromium oxide, rhenium heptoxide, heptasulfide and heptaselen-ide, and sulfides of cobalt, molybdenum and tungsten. 

Gennamiun(II) sulfide, 4419 Goldail) sulfide, 0116 Iron disulfide, 4401 lron(ll) sulfide, 4400 lron(lll) sulfide, 4404 Manganese(ll) sulfide, 4706 Manganese(lV) sulfide, 4707 Merciuy(ll) sulfide, 4607 Molybdemun(lV) sulfide, 4719 Potassium sulfide, 4670 Rhenium(Vll) sulfide, 4891 Ruthenimn(lV) sulfide, 4895 Samarium sulfide, 4899 Silver sulfide, 0026 Sodimn disulfide, 4812 Sodimn polysulfide, 4813 Sodimn sulfide, 4811 Strontimn sulfide, 4901 Tantalum(lV) sulfide, 4903 Tetrakis(butylthio)uranimn, 3731 Thorium oxide sulfide, 4826 Tin(II) sulfide, 4900 Tin(IV) sulfide, 4902 Titaniiun(IV) sulfide, 4904 Uranium(IV) sulfide, 4905 Zirconium oxide sulfide, 4827... 

Metathesis is the rupture and reformation of carbon—carbon bonds, for example of propylene into ethylene plus butene. Catalysts are oxides, carbonyls or sulfides of Mo, W, or rhenium. 

THE OXIDE AND SULFIDE CATALYSTS OF TRANSITION METALS OTHER THAN RHENIUM 43... 

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