Journal Articles (before-1995)

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    Carbonylation of Methanol and Ethanol on a Rhodium-Zeolite Catalyst
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74 (09-12), 1978) Christensen, Bjarne; Scurrell, Michael S.
    The carbonylation of methanol and ethanol on a rhodium-X zeolite has been studied. Particular emphasis has been placed on the effect of the concentration of the required alkyl iodide “promoter” on the selectivity of the reaction. A maximum in selectivity for carbonylation is observed for both alcohols as the alkyl iodide content of the reactant stream is increased. The side products are dimethyl ether and ethylene with methanol and ethanol respectively. Some comparative experiments with either rhodium-on-carbon or the unmodified NaX support show that at least for ethanol the zeolite support offers a sufficiently high activity to account for the rate of formation of side product under carbonylation conditions. For methanol carbonylation the necessity to employ near-stoichiometric quantities of methyl iodide and the effects which the absence of “promoter” has on catalyst behaviour are discussed. Comparison between the action of rhodium catalysts in homogeneous and heterogenised forms leads to the conclusion that close similarities in behaviour exist, probably due to the operation of a common mechanism.
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    Ionic Solvation in Methanol+Water Mixtures: Free Energies of Transfer from Water
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (5), 1973) Wells, Cecil F.
    The free energy of transfer ΔG°t(H+) of the solvated proton from water to methanol + water mixtures up to 50 % w/w methanol is considered as the sum of two processes, the transfer of a tetrahedral aqua-proton from water into the mixture using the Born expression and the subsequent replacement of an H2O molecule in the tetrahedron by a methanol molecule according to the equilibrium, H+(H2O)4solv+ CH3OHsolv⇌ H+(CH3OH)(H2O)3solv+ water. These values for ΔG°t(H+) are subsequently used to derive values for ΔG°t(halide ion) from the ΔG°t for the appropriate hydrogen halides, and ΔG°t(Cl–) then used to produce values of ΔG°t for other cations from ΔG°t for simple salts. These values for ΔG°t for the single ions are discussed with respect to solvation of ions by H2O and CH3OH molecules and structural effects in the bulk solvent.
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    Nuclear Magnetic Resonance Studies of Preferential Solvation: Part 2.—Thermodynamic Treatment and application to Methanol + Water Solvents
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (5), 1973) Covington, Arthur K.; Newman, Kenneth E.
    Prom a detailed consideration oi the thermodynamics of preferential solvation of ions in a binary solvent mixture, making reasonable assumptions about the variation of chemical potential of the variously solvated ions with solvent composition, it is shown how the variation of the free energy of transfer of a salt from water to mixed aqueous solvents derived from e.m.f. measurements can be related to spectroscopic information.