Ruthenium supported

KAAP [Kellogg advanced ammonia process] The first high-pressure process developed for synthesizing ammonia from its elements which does not use an iron-containing catalyst. The reformer gas for this process is provided by the KRES process. The catalyst was developed by BP it contains ruthenium supported on carbon. Developed by MW Kellogg Company in 1990 and first installed by the Ocelot Ammonia Company (now Pacific Ammonia) at Kitimat, British Columbia, from 1991 to 1992. Another plant was installed at Ampro Fertilizers in Donaldsonville, LA, in 1996. 

Heterogeneous catalysts, either as metals or as metal oxides, are easier to separate from the effluent stream and when coated onto porous carriers are more active than homogeneous catalysts in promoting oxidation. Some examples of heterogeneous catalyzed systems operating at subcritical temperatures (WAO conditions) include the following ruthenium supported on cerium (IV) oxide, the most active metal catalyst among precious metals... 

Imamura S, Hirano A, Kawabata N. Wet oxidation of acetic acid catalyzed by Co-Bi complex oxides. Ind Eng Chem Prod Dev 1982 21(suppl 4) 570-575 Imamura S, Fukuda I, Ishida S. Wet oxidation catalyzed by ruthenium supported on cerium(IY) oxides. Ind Ing Chem Res 1988 27(suppl 4) 718-721. 

Vocanson et al. [ 111 ] have described the use of ruthenium supported on ceria, Ce02, as a catalyst for the aerobic oxidation of alcohols. Primary and secondary alcohols are oxidized to the corresponding aldehydes (carboxylic acids) and ketones, respectively, at elevated temperatures (above 140 °C). Surprisingly, allylic... 

Ruthenium supported on oxides is a catalyst of various reactions. It is active in methanation reactions [e.g. 1, 2, 3], in Fischer-Tropsch synthesis [e.g. 4, 5, 6], in CO oxidation [7, 8], in the synthesis of methyl alcohol [9], 1" the redu ction of NO to nitrogen CIO] and in hydrogenolysis of ethane [11] and of butane [12]. Ru supported on carbon is supposed to replace the iron in ammonia synthesis [13]. Lately ruthenium supported on oxides is intensively investigated as a potential... 

Rare earth oxides are useful for partial oxidation of natural gas to ethane and ethylene. Samarium oxide doped with alkali metal halides is the most effective catalyst for producing predominantly ethylene. In syngas chemistry, addition of rare earths has proven to be useful to catalyst activity and selectivity. Formerly thorium oxide was used in the Fisher-Tropsch process. Recently ruthenium supported on rare earth oxides was found selective for lower olefin production. Also praseodymium-iron/alumina catalysts produce hydrocarbons in the middle distillate range. Further unusual catalytic properties have been found for lanthanide intermetallics like CeCo2, CeNi2, ThNis- Rare earth compounds (Ce, La) are effective promoters in alcohol synthesis, steam reforming of hydrocarbons, alcohol carbonylation and selective oxidation of olefins. 

Promotor of hydrogenation. Rylander and Kaplan found stannous chloride to be the most effective of several promotors for the hydrogenation of heptaldehyde with platinum and ruthenium supported on carbon. 

Zeolites are also able to decompose N2O. Li and Armor (11] prepared 25 zeohte samples by exchanging the cation Na+. These catalysts were tested for the catalytic decomposition of N2O. The Co- and Cu-exchanged zeolites are active at temperatures ranging from 623 K to 673 K. Rhodium and ruthenium supported on ZSM-5 are active catalysts between 523 and 573 K. 

On many supports, ruthenium converts synthesis gas with high selectivity into lower alkanes, notably methane.. However, when ruthenium is supported on certain basic oxides, such as lanthana and ceria, highly selective production of lower olefins has been reported (1,2). One of the aims of this research was to improve the activity and selectivity of ruthenium supported on rare earth oxides (REO). As commercially available REO are of low surface area (<15m2g"l), routes to higher surface area materials have also been developed (3). 

Preparation of ruthenium supported catalysts for wet air oxidation of p-hydroxybenzoic acid... 

Ti02 and Z1O2 aerogels were successfully employed as supports for ruthenium supported catalysts. These catalysts were found to be very active for wet air oxidation of p-HBZ acid. Furthermore, the use of nitric acid as hydrolysis agent and Ru(N0)(N03)3 as metal precursor leads to the more efficient catalyst. When these conditions were used, ZrOa enhances the catalytic properties of the ruthenium phase. This result points out the important role of the support on the properties of the dispersed metal phase. Further investigations to improve BET surface area and thermal stability of the support are in progress. 

Azevedo DC, Lizcano-Valbuena WH, Gonzalez ER (2004) An impedance study of the rate determining step for methanol oxidation on platinum and platinum-ruthenium supported on high surface area carbon. J New Mater Electrochem Syst 7 191-196... 

A ruthenium supported on graphite catalyst (Ru/G) could also be obtained by using the modified impregnation method. Ruthenium nanoparticles are very imlform and the size of particles was nearly 10 nm. The hydrogen generation rate for hydrolysis of sodium borohydride has been reported as 32.3 L min g and the activation energy is calculated as 61.1 kJ mol [68]. 

Most current technology development is focused on the use of platinum (or platinum and ruthenium) supported on carbon particles, in order to reduce the amount of platinum required on the anode down to 0.05-0.45 mg cm", as described in [10]. These types of anodes are prone to degradation during fuel starvation due to the reaction in Equation 17.6, the oxidation of carbon, which is catalyzed by the presence of platinum [11]. This reaction proceeds at an appreciable rate at the electrode potentials required to electrolyze water in the presence of platinum (greater than approximately 1.4 V [24). This is shown schematically in Figure 17.4. The catalyst support is converted to CO2, and Pt and/or Ru particles may be lost from the electrode, resulting in loss of performance. 

In the CWAO of carboxylic acids, noble metals give the best performances and stability. Ruthenium supported over ceria-zirconia shows the best performance. These catalysts are also preferable for CWAO of N-containing compounds such as aniline. Over Ru/Ce02, ammonium ions formed in the reaction are selectively oxidized into molecular nitrogen in the temperature range of 180 to 200°C, but above 200°C nitrite and nitrate ions form. 

Kishore, D. and Rodrigues, A. (2007). Catalytic Oxidation of Isophorone to Ketoisophorone over Ruthenium Supported MgAl-hydrotalcite, Catal. Comm., 8, pp. 1156-1160. 

Yamaguchi, K. and Mizuno, N. (2003). Scope, Kinetics, and Mechanistic Aspects of Aerobic Oxidations Catalyzed by Ruthenium Supported on Alumina, Chemistry-A European Journal, 9, pp. 4353-4361. 

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