Kinetic Analysis of Mixed Alcohol Synthesis from Syngas over K/MoS₂ Catalyst

Abstract

A mechanistic kinetic model has been developed to describe the synthesis of mixed alcohol from syngas over 17 wt % K2CO3 promoted MoS2 catalyst. A rigorous kinetic network has been considered on the basis of a CO insertion mechanism for this reaction system. The kinetic model was derived by using LHHW formalism and steady-state approximation for reaction intermediates. The kinetic parameters were estimated by nonlinear regression of the experimental data using the method of reparameterization. The model successfully predicts the formation and distribution of the products within the range of experimental conditions. Mixed alcohol formation was maximized when the temperature was ∼320 °C independent of the pressure. With the higher pressure, the optimal reactor space time is longer, and the produced alcohols further react with syngas to form paraffins when the reaction temperature is higher than 320 °C and the space time exceeds its optimum. The H2/CO molar feed ratio affected the product composition of mixed alcohols and hydrocarbons, and their experimental and theoretical composition obeyed the Schulz−Flory distribution. The kinetic model developed in the present study has been simulated to examine the effect of operating conditions on the formation of mixed alcohols in the wider range of reaction conditions.