Temperature Dependence Vant Hoff Equation

The magnitude of the equilibrium displacement depends on AT and AH for the equilibrium. The sign of AH1 determines the direction of the shift in accordance with the Vant Hoff equation. A typical equipment might discharge 10-25 kV in 1 cm3 of solution. Such a voltage discharge may produce about 45 J in 10-6 s corresponding to 4.5 x 107 W and temperature rise of 5-10°C. 

To analyze sorption of penetrants, including hydrocarbons, in glassy polymers, the dual-mode sorption model is most frequently used. For a number of glassy polymers, correlations between the constants of the dual-mode sorption model and the condensabUity of hydrocarbons have been established (see, e.g.. Figure 9.4a through 9.4c and data presented in Refs. [18-20]). Temperature dependence of model constants is described by Vant-Hoff equation, where the exponent contains heat of penetrant sorption A//s. This quantity is essentially dependent on the heat of penetrant condensation, AHcond- A//s = AH ond + A//i, where AHi is partial molar enthalpy of penetrant dissolution in the polymer, AHi = [d( AGi/T)/d( l/T)]c, AGi is the partial molar free... 

The temperature dependence of the Henry constant obeys the vant Hoff equation ... 

The temperature dependence of K follows the usual vant Hoff equation [Eq. (2.19)]. 

The equilibrium constant which appears in the denominator of the time constant will vary with temperature according to a vant Hoff equation (K- whereas the temperature dependence of the pore diffusivity... 

Thermal swing is probably the most common system. The temperature dependence of the adsorption equilibrium constant is governed by a vant Hoff equation [Eq. (2.20)]. Since adsorption is an exothermic process and since the more strongly adsorbed species generally have the higher heats of adsorption, a large decrease in the adsorbed phase concentration in equilibrium with a specified fluid concentration may be achieved by a comparatively modest increase in temperature. This means that at elevated temperatures the iso-... 

The temperature dependence of ki ) is given by two Arrhenius equations and one vant Hoff relation ... 

This approach assumes the constancy of AH over the temperature range that is, its accuracy depends largely on the linearity of flie vant Hoff regression. Estimation of AS from R X intercept of the regression, as implied by equation [13.21.2.15], is invalid due to the large propagation of measurement errors encountered in extrapolating the 1/T (x-... 

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