Methanol to Gasoline over La/HZSM-5 Catalyst Modified by Na2CO3
HZSM-5 catalysts with SiO2/Al2O3 molar ratio of 80 were treated with 0.4 mol/L Na2CO3 solution at 80°C for 2 h to improve diffusion properties. Further, some of these catalysts were modified by impregnation of La (NO3)3. These catalysts characterized by XRD and BET were evaluated in a fixed bed reactor for conversion of methanol to gasoline (MTG) reaction. The Na2CO3 treatment results in formation of mesoporous structure in ZSM-5 zeolite. Meanwhile, LaZSM-5/AT catalyst exhibits significantly enhancement in catalytic lifetime and liquid hydrocarbons yield as well as selectivity of isoparaffin and olefin. The conversion of methanol remains above 80 % over 125 h on LaZSM-5/AT catalyst under atmospheric pressure, 380°C and weight hourly space velocities (WHSV) of 1.5 h-1.