Dissolved catalytic oxidation

The catalytic oxidation of S02 produces S03, which reacts with water to produce sulfuric acid, and it dissolves in sulfuric acid to produce disulfuric acid or oleum, H2S207. Solid S03 exists as the trimer (S03)3 but there are different crystalline forms known. 

Sugimura, Y., and Y. Suzuki. 1988. A high temperature catalytic oxidation method for the determination of non-volatile dissolved organic carbon in seawater by direct injection of a liquid sample. Marine Chemistry 41 105-131. 

The catalytic oxidation of liquid hydrocarbons with air or oxygen. Since oxygen is not very soluble in the liquid, while the hydrocarbon could well be present in high concentration we could end up in extreme 1 (excess of B). The removal of dissolved organics from industrial waste water by catalytic oxidation as an alternative to biooxidation. Here oxygen is not very soluble in water, but the organic waste is also present in low concentration. It is therefore not clear in what regime the kinetics lie. The catalytic oxidation of phenol is an example of such an operation. 

ECO Purification Systems USA, Inc. (EPS) has patented the ECOCHOICE process. This technology uses catalytic oxidation to destroy dissolved organic contaminants in a fixed-bed reactor. Ozone and the polluted water pass through the reactor where the organic contaminants are oxidized to form carbon dioxide and water. Clean water is discharged, and residual ozone is recycled or destroyed within the treatment system. 

Hoffmann, M. R., and D. J. Jacob, Kinetics and Mechanisms of Catalytic Oxidation of Dissolved Sulfur Dioxide in Aqueous Solution An Application to Nighttime Fog Water Chemistry, in SO2, NO, and N02 Oxidation Mechanisms Atmospheric Considerations, Acid Precipitation Series, Vol. 3, pp. 101-172 (J. I. Teasley, Series Ed.), Butterworth, Stoneham, MA, 1984. 

Catalytic oxidation is the most important technology for the conversion of hydrocarbon feedstocks (olefins, aromatics and alkanes) to a variety of bulk industrial chemicals.1 In general, two types of processes are used heterogeneous, gas phase oxidation and homogeneous liquid phase oxidation. The former tend to involve supported metal or metal oxide catalysts e.g. in tne manufacture of ethylene oxide, acrylonitrile and maleic anhydride whilst the latter generally employ dissolved metal salts, e.g. in the production of terephthalic acid, benzoic acid, acetic acid, phenol and propylene oxide. 

Researchers returned to the oxidation of ammonia in air, (recorded as early as 1798) in an effort to improve production economics. In 1901 Wilhelm Ostwald had first achieved the catalytic oxidation of ammonia over a platinum catalyst. The gaseous nitrogen oxides produced could be easily cooled and dissolved in water to produce a solution of nitric acid. This achievement began the search for an economic process route. By 1908 the first commercial facility for production of nitric acid, using this new catalytic oxidation process, was commissioned near Bochum in Germany. The Haber-Bosch ammonia synthesis process came into operation in 1913, leading to the continued development and assured future of the ammonia oxidation process for the production of nitric acid. 

A detailed review of the stabilities of inorganic selenium species, i.e. Se and Se, in water has been published (Heninger et al., 1997). No loss of either species was detected in aqueous solutions stored at — 20°C for 1 year. The concentrations studied were 10 and SOngmF1 (Cobo et al., 1994). Losses of Se occurred at higher temperatures for solutions of pH 2 and 6 stored in polyethylene containers. The maximum time for preservation was 1-2 months. In another investigation (Heninger et al., 1997), aqueous samples stored in Teflon containers at 4°C lost 29% of Se by oxidation in less than 1 month. The authors stated that catalytic oxidation of Se had occurred as a result of chlorine produced by a reaction between dissolved chloride and oxygen. 

The Oxidation of Sulphur Dioxide. - This very important reaction is probably the oldest one in which vanadium catalysts have been used in practice. It is generally assumed that in these catalysts the vanadium is present dissolved in a liquid mixture of alkali metal meta- and/or pyro-sulphates. Villadsen and Livbjerg3 recently reviewed the properties of these supported liquid phase catalysts and showed that a number of questions still remain unanswered. Urbanek et al.la and Kenney75 presented reviews of the catalytic oxidation of S02, considering both the kinetics and problems of industrial reaction design. 

Solomon CM, Lessard EJ, Keil RG, Foy MS (2003) Characterization of extracellular polymers of Phaeocystis glob-osa and P. antarctica. Mar Ecol Prog Ser 250 81-89 Sugimura Y, Suzuki Y (1988) A high temperature catalytic oxidation method for the determination of non-volatile dissolved organic carbon in seawater by direct injection of a liquid sample. Mar Chem 24 105-131 Sunda WG, Huntsman SA (1995) Iron uptake and growth limitation in oceanic and coastal phytoplankton. Mar Chem 50 189-206... 

The standard electrode potential of the electrode semireaction Pd " " + 2 e = Pd° is E°j2+ pj = 0.987 V in respect to NHE. This indicates the principal possibhity of dissolving palladium metal in a strong acid under the action of air oxygen because the potential of the electrode semi reaction O2 + 4H + 4e = 2H2O equals E° = 1.228 V in respect of NHE. Win the palladium metal dissolve in an acidic solution where the catalytic oxidation of Fe cations... 

Mercaptobenzothiazole is believed to function as a catalytic poison by adsorption. Cyanide converts CU2O particles, predecessors of Cu particles, into an inactive cuprous cyanide complex. Dissolved oxygen oxidizes CU2O particles to form the original Cu(II) complex. It is important to note that, according to the above stabilization principle, these stabilizers function by acting on the particles before their radii exceed the critical value of f. ... 

Catalytic oxidation is now used by the smelting industry to convert SO2 into SO3. This is then dissolved in water to make solutions of H2SO4 (up to 80% by mass). The gases containing SO2 are passed through a series of condensers containing catalysts to speed up the reaction. In some cases the impure H2SO4 can be used in other operations in the same plant. 

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