(154b) Comparison of Equilibrium Constant of the Reaction Water Gas Shift (WGS) for Determination of the Conversion of the Reaction

Oil is a major source energy and has a strong impact on environment pollution by the gases emitted in the burning of its derivatives, for example, carbon monoxide, carbon dioxide. A way of reducing the emission of such gases as for example CO is converting by means of reaction in products less aggressive to the environment as is the case of the hydrogen gas. The reaction water-gas-shift is a secondary reaction that produce hydrogen and carbon dioxide from the reaction carbon monoxide with water, this reaction occurs in the synthesis of Fischer-Tropsch, in the synthesis methanol, conversion of hydrocarbons by reform among others. The equilibrium composition of the reaction can be estimated from the reaction equilibrium constant under various temperature, pressure and feed composition conditions. The equilibrium constant can be estimated from thermodynamic properties such as enthalpy and entropy, the constant suffers great influence as temperature. In the literature there are some correlations to determine the equilibrium constant of the WGS reaction. For the modeling was considered real system, the reaction occurs in the gas phase, the thermodynamic equilibrium occurs, the coefficient of fugacity and the Soave/Redlich/Kwong equation of state were used. The whole simulation was developed in the Scilab, which obtained the equilibrium constant with the models found in the literature and compared with data of equilibrium constant also found in the literature, for the model that presented the best result was used for the simulations, the chosen conditions were for several temperature and feed conditions (CO/H₂O). The results obtained were the conversion versus CO/H₂O ratio for various temperatures, the conversion versus temperature for several CO/H₂O ratio and the formed hydrogen composition versus the CO/H₂O ratio for various temperatures.