Catalytic Dehydration Of Ethanol Research Articles

Surface Studies and Catalytic Dehydration of Ethanol over Doped CdO

Surface Studies and Catalytic Dehydration of Ethanol over Doped CdO

A METHOD FOR THE EVALUATION OF EQUILIBRIUM CONSTANTS

As a method to evaluate equilibrium constants, it is proposed that rate constants be estimated through Box-Draper''s procedure and the constants thus obtained be employed for the evaluation of equilibrium constants. The method allows the precise calculation of rate constants and, subsequently, the calculation of equilibrium constants under circumstances where the simultaneous measurements of several concentration responses are available and the error variances of these measurements are not equal. The concentrations of ethanol, water, ethylether, and ethylene obtained for a catalytic dehydration of ethanol were utilized to demonstrate the method by evaluating the equilibrium constant of the dehydration reaction. A satisfactory agreement was obtained between the resulting equilibrium constant and the literature value.

Kinetics of the catalytic dehydration of ethanol over alumina

The kinetics of the vapour-phase catalytic dehydration of ethanol over alumina have been studied in a static system in the temperature range which favours the formation of ethylene and water. The first-order rate constant, k, for the reaction is given by k= 3 × 108 exp –26,600/RT sec.–1 for surface coverages, θ, up to 0·8 At catalytic temperatures in the range 334–418° the heat of adsorption and the entropy of adsorption (referred to a standard state of 1 atm.) are shown to be approximately –16·1 kcal. mole–1 and –19·4 cal. deg.–1 mole–1, respectively. It is suggested that the latter value is consistent with a mobile layer of ethanol, and an estimate of the partition function of the activated complex of about 109 at 360° also implies that anchorage of ethanol molecules at fixed surface sites is not required for the dehydration reaction.