Study of mechanism and kinetic modeling of CO hydrogenation reaction over the impregnated Co‐Ni/Al2O3 catalyst

Abstract

AbstractAn investigation of the kinetic and mechanism of CO hydrogenation reaction was performed on impregnated Co‐Ni/Al2O3. Determination of kinetic parameters from the experiments was carried out in a micro fixed‐bed reactor. Kinetic evaluations were performed under various operational conditions of T = 473–673 K, p = 1–14 bar, H2/CO = 1–3, and GHSV = 4,500 hr−1. Kinetic models and rate equations for CO consumption were obtained by using two main‐type rate equations of Langmuir‐Hinshelwood‐Hougen‐Watson (LHHW) and Eley‐Rideal (ER). Estimation of various kinetic parameters was performed using a nonlinear regression method. According to the obtained experimental results and using statistical criteria, one kinetic expression based on the LHHW mechanism (‐rCO = kp.bCO.PCO. bH2. PH2/[1+ bCO.PCO + bH2.PH2]2) was chosen as the best‐fitted model. For this fitted model, the activation energy was found to be 109.2 kJ/mol. Characterization of the catalyst was also performed using X‐ray diffraction (XRD), BET, scanning electron microscopy (SEM), and energy‐dispersive x‐ray spectrometer (EDS) techniques.