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Ruthenium-melt catalysis

Mention must also be made of the work of J.F. Knifton from Texaco who has demonstrated the use of ruthenium melt catalysis for the production of a wide range of commodity chemicals (alcohols, acids and esters) and fuels (j ). [Pg.6]

Acetic acid is an important commodity chemical (U. S. demand ca. 2.9MMM Ib/yr) already targeted for generation directly from CO/H2 (1). Here we describe a new application for ruthenium "melt" catalysis, where synthesis gas is for the first time converted directly to acetic acid in >80 wt % selectivity in the crude liquid product (eq. 1) (2,3). [Pg.98]

Glycol from Syngas - Ruthenium Melt Catalysis... [Pg.5]

Here we describe a new route to the synthesis of N,N-dimethylform-amide using synthesis gas and ammonia as the only chemical building blocks (eq. 26). Once again this involves an adaption of ruthenium melt catalysis (13). At about the time this work was published, Marsella and Fez of Air Products, disclosed a similar synthesis using solvent-solubilized ruthenium catalysis (79). [Pg.32]

Jn a potentially far reaching application for melt catalysis by the transition metals, we at Texaco have demonstrated the synthesis of a range of commodity chemicals and fuels directly from CO/H2 via the use of ruthenium-containing molten salt catalysis. Products include ethylene glycol, Ci-C4 alcohols, acetic acid, acetate esters, C2+ olefins and vicinal glycol esters. In its simplest form, this new class of melt catalyst comprises one or more ruthenium sources, e.g. ruthenium carbonyls, oxides, complexes, etc. dispersed in a low-melting (m.p. <150 C) quaternary phosphonium or ammonium salt (e.g. tetrabutylphos-phonium bromide). The key components are selected such that ... [Pg.2]

Figure 1. Ethylene glycol from synthesis gas via ruthenium rhodium bimetallic melt catalysis. Effect of Rh Ru molar ratios. Synthesis conditions as per Table II. Effect of varying [Rh],0 effect of varying [Ru],... Figure 1. Ethylene glycol from synthesis gas via ruthenium rhodium bimetallic melt catalysis. Effect of Rh Ru molar ratios. Synthesis conditions as per Table II. Effect of varying [Rh],0 effect of varying [Ru],...
A more detailed study into the mechanism of ruthenium bimetallic melt catalysis for alcohol/ester production has been undertaken for the ruthenium-cobalt combination. Specifically, for the triruthenium dodecacarbonyl-dicobalt octacarbonyl couple, dispersed in tetrabutyl-phosphonium bromide, we have defined the experimental limits of this catalysis, demonstrated multiple catalyst recycle (7) and most importantly, identified some of the relationships linking catalyst productivity, alcohol-ester carbon distributions, and certain key operating parameters with the catalytically active metal carbonyl species present in these reaction media. [Pg.16]

The first example of homogeneous transition metal catalysis in an ionic liquid was the platinum-catalyzed hydroformylation of ethene in tetraethylammonium trichlorostannate (mp. 78 °C), described by Parshall in 1972 (Scheme 5.2-1, a)) [1]. In 1987, Knifton reported the ruthenium- and cobalt-catalyzed hydroformylation of internal and terminal alkenes in molten [Bu4P]Br, a salt that falls under the now accepted definition for an ionic liquid (see Scheme 5.2-1, b)) [2]. The first applications of room-temperature ionic liquids in homogeneous transition metal catalysis were described in 1990 by Chauvin et al. and by Wilkes et ak. Wilkes et al. used weekly acidic chloroaluminate melts and studied ethylene polymerization in them with Ziegler-Natta catalysts (Scheme 5.2-1, c)) [3]. Chauvin s group dissolved nickel catalysts in weakly acidic chloroaluminate melts and investigated the resulting ionic catalyst solutions for the dimerization of propene (Scheme 5.2-1, d)) [4]. [Pg.214]

Ruthenium, cobalt and halogen are the key elements of this catalysis (2), although ruthenium in combination with halogen-containing zirconium and titanium derivatives is also effective (3). In the case of the Ru-Oo couple, the highest yields of acetic acid may generally be achieved with ruthenium oxide, carbonyls and complex derivatives in combination with various cobalt halides dispersed in low-melting quaternary phosphonium halide salts (2). [Pg.98]

The preparation of ethylene glycol directly from synthesis gas via homogeneous rhodium (14-20), ruthenium (21-26), and cobalt (27-30) catalysis has generally been limited by the high pressures necessary to effect reaction and the modest turnover frequencies. We have demonstrated the preparation of ethylene glycol and its monoalkyl ether derivatives from CO/H2 (eq. 1) using ruthenium or a Ru-Rh catalyst combination dispersed in a low-melting quaternary phosphonium or ammonium salt such as tetrabutylphosphonium bromide. Monohydric alkanols are the major by-products data in Table 1 illustrate typical preparations. The important features of this catalysis are ... [Pg.4]


See other pages where Ruthenium-melt catalysis is mentioned: [Pg.42]    [Pg.42]    [Pg.6]    [Pg.9]    [Pg.9]    [Pg.106]    [Pg.178]    [Pg.4120]    [Pg.4119]    [Pg.33]   
See also in sourсe #XX -- [ Pg.98 ]




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Ruthenium catalysis

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