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activation energy. For this oscillation system, A 0 was found to be 4.24 × 10 5 s −1 and A was 148.5 kJ mol −1 . The change in oscillation waveforms, frequencies and amplitudes also resulted in variations in product selectivities. When the

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]. The specificity of cesium promotion in the epoxidation of BD follows from kinetic data. The presence of cesium affects the rate-determining step of the dissociation of O 2 on vacant Ag sites [ 14 ] by lowering the activation energy of the

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activation energy is brought down [ 25 , 26 ]. Dabi [ 27 ] proposed that the possible mechanism for the urethane reaction of butanol with phenyl isocyanate in highly polar solvents included two steps: first, the isocyanate forms a complex with the solvent

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, M. Scurtu, S. Mihaiu, M. Caldararu, and M. Zaharescu

-activity catalysts [ 9 , 10 ]. For example, Ce 0.8 Sn 0.2 O 2 and Ce 0.3 Sn 0.7 O 2 mixed oxides were found to have higher CO oxidation activity and lower values of activation energy as compare to SnO 2 and CeO 2 single oxides [ 9 ]. A similar conclusion was

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catalyst surface adsorption sites and the catalytic activity [ 37 ]; (3) silver doping made the activation energy (Ed) of the catalyst surface adsorbed oxygen (O − and O 2− ) decrease significantly, resulting in the improvement of the catalyst activity

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%) Fig. 4 shows the Arrhenius plots of toluene and DBT in the considered temperature range, where the rate constants are evaluated by the ln C –time plot of Fig. 3 . The calculated activation energy of DBT (15.14 kJ/mol) was much lower than that of

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Andrés Pena, Santiago Veiga, Mariángeles Sapelli, Natalia Martínez, Victoria Márquez, Eduardo Dellacassa, and Juan Bussi

formation is the main rate controlling path during the initiation paths of the mechanism [ 15 ]. This is in agreement with theoretical calculations on aerobic oxidation of hydrocarbons showing the high activation energy involved in the initial stages in

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higher activation energy than the thermodynamics-governed one (formation of 5-ol with 6-membered ring). Anyway, a high temperature is beneficial to the glycerol conversion and solketal production, however a too high temperature is unfavorable due to the

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together as (10) (11) (12) where is the rate constant for the rate of consumption of 1-dodecene. As a result the rate equations can be rewritten as (13) (14) (15) here R , , and represent the gas constant, reference temperature, activation

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Natpakan Srisawad, Wasu Chaitree, Okorn Mekasuwandumrong, Artiwan Shotipruk, Bunjerd Jongsomjit, and Joongjai Panpranot

molecular weight alkanes, alkenes and alcohols [ 2 – 6 ]. The methanation of CO 2 was reported to proceed with a lower activated energy than the methanation of CO [ 7 ]. The lower exothermicity of the overall reaction of CO 2 as compared with CO makes

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