(139e) Kinetics of Noncatalytic Water Gas Shift Reaction in a Supercritical Water Medium

The kinetics of the noncatalytic water gas shift reaction in a supercritical water medium was investigated at various temperatures in a specially designed 0.4-L Haynes Alloy 230 tubular reactor. Experiments were performed noncatalytically in a continuous mode of operation at a constant pressure of 24.1 MPa, water to CO ratio of 22 to 1, and at temperatures varying from 770 to 1050 K. The reactor effluent gas consisted of H₂, CO₂, and CO, with the CO concentration decreasing with increasing temperature. The CO concentration in the effluent gas reached a minimum of 2% at 1050 K. Using global first order kinetics of the type k' = A?exp (-Ea/RT) and provided that water was in excess so as to negate the influence of water concentration on the rate law, the kinetic parameters for the rate equation for CO conversion were determined to be: A =2.512 x 10⁵ s^-1 and Ea = 1.325 x 10⁵ J/mol?ºK.