Hydrogen peroxide and an immobilized derivative of soybean peroxidase, covalently bound to a glass support, were used in a continuous tank reactor to remove phenol from aqueous solutions. An efficiency of about 80% was attained in phenol removal in the best of the operational conditions assayed. With the aim of scaling up the process to pilot-plant scale, the influence of the main plant operational variables, enzyme and substrate concentrations and flow rate, on the removal efficiency was studied. The continuous reactor was operated under isothermal conditions at the optimal temperature established in the literature for this system. As a first approximation to the industrial application of the process. no buffer solutions were used. Additionally, and to check the validity of a generalized Ping Pong bisubstrate kinetics for the enzymatic reaction, obtained from an expanded version of the Dunford mechanism previously published, and assuming an ideal mixing flow for the continuous tank reactor, a transient design model was developed. By using the intrinsic kinetic parameters obtained in a previous work, where the kinetic model was developed, the reactor model was solved and the theoretical conversion values were calculated. The nearness of the experimental and calculated conversion values confirmed that the proposed kinetic equation and the design model, as well as the intrinsic kinetic parameters previously determined, can be used to predict the behaviour of the reactor under conditions of slow enzyme deactivation, although, for further applications, an improved version of the model deactivation equation is necessary. (C) 2008 Elsevier B.V. All rights reserved.