Improvement of HZSM-5 catalytic performance by rice husk ash addition for methanol to hydrocarbons process

Abstract

Abstract The catalytic conversion of methanol to hydrocarbons (MTH) of gasoline has been studied over the modification of HZSM-5 zeolite catalysts, which were prepared by different ratios of rice husk ash (RHA) addition. The catalysts were characterized by BET, XRD, XRF, NH3-TPD, FT-IR and SEM techniques. The dehydration of methanol over prepared catalysts was carried out in a fixed-bed reactor at 300 oC with a constant flow rate of methanol under 1 atm of N2. The liquid hydrocarbons product was analyzed by GC-MS. The analysis showed that the major product provided by RHA-HZSM-5 catalysts was aromatic hydrocarbon-rich. According to the experimental results, the methanol conversion to hydrocarbons has been found to be a function of RHA ratio. The aromatic product selectivity was increased but that of the acidity of catalyst was decreased with the increase of RHA ratio. The study indicated that the hydrocarbon product distribution of the catalysts treated by RHA significantly depended on the acidity of catalyst.