KINETIC MODELING OF SERIES REACTION CH4-CH3OH-DME WITH CuO-ZnO/gamma-Al2O3 CATALYST

Abstract

A kinetic model was proposed for the synthesis of methane to be dimethyl ether (DME) in one reaction step from (CH₄ + O₂) and (CH₃OH) to dimethyl ether using kinetic CuO-ZnO /gAl₂O₃ catalyst parameters. The bifunctional catalyst of the series kinetic reaction model according to the experimental results obtained under isothermal conditions in a pipe flow reactor under various operating conditions: 225-325 ° C; 10 bar gauge; Residence time, 16-57.0 (g Catalyst) hour (mole CH₄) ^-1. An important step for modeling is the synthesis of methanol from (CH₄ + O₂) and the synthesis of (CH₃OH to DME) is methanol dehydration (very fast), and water-shifting and CO₂ (equilibrium) reactions. The effects of water inhibition and CO₂ were also taken into account in the synthesis of methanol and the formation of hydrocarbons. The dehydration advantage of methanol can achieve higher yields above 60 % methanol that was converted to DME and the remaining 5% methanol if (CH₄ + O₂) comes in at 10 bar gauge and 375 ° C. At higher temperatures produces CO₂ and H₂O. Methane-methanol-DME series reaction model follows single-order gas phase reaction to methane and methanol with k₁ = 0.195 minutes^-1 and k₂ = 0.115 minutes^-1 The time and maximum concentration occurs in the formation of methanol constituents 9.5 minutes and 0.44 mole