Development of a macro-micro kinetic model for CO hydrogenation over Co–Ni catalyst

Abstract

A novel approach in kinetic study of CO hydrogenation reaction over Co–Ni/Al2O3 catalyst was described. The experimental data were collected using a fixed bed micro reactor under next conditions: pressure 2–12 bar, temperature 230–280°C, molar ratio H2: CO = 1–3, space velocity 2000–2700 h–1. A new Langmiur–Hinshelwood (LH) kinetic model on the basis of formyl mechanism was developed. The apparent activation energy of LH kinetic model, bond energy of carbon, oxygen, hydrogen and some surface intermediate on catalyst surface, activation energies of some surface reactions and catalyst surface coverage were estimated from a new combined LHHW/UPI–QEP methodology. It was postulated that under reaction conditions used, CH2 formation through H-assisted CO dissociation is probably dominant mechanism of hydro-genation over Co–Ni catalyst.