Kinetic modelling of the catalytic steam reforming of HDPE pyrolysis volatiles

The kinetics of the steam reforming of HDPE pyrolysis volatiles is studied on a Ni commercial catalyst in a fluidized bed reactor in-line with the pyrolysis reactor (a conical spouted bed reactor at 500 oC). Steam reforming reactions have been carried out under the following conditions: 600-700 oC and space time 0-16.7 gcat min gHDPE-1. Based on the composition of HDPE pyrolysis volatiles, a kinetic scheme is assumed with four reactions (C5+ hydrocarbon reforming, C2-C4 hydrocarbon reforming, CH4 reforming and WGS reaction). Moreover, the kinetics of the deactivation has been quantified with an expression dependant on C5+ hydrocarbon concentration (coke precursors). Calculation of the kinetic parameters is conducted by nonlinear multiple regression, fitting the experimental data to those calculated by the mass conservation equations for each component in the reaction medium. The overall kinetic model proposed describes accurately the evolution of the main products (H2, CO2, CO) with time on stream in the ...