Production of gasoline range hydrocarbons from methanol on hierarchical ZSM-5 catalyst prepared with n-propylamine template

In methanol to gasoline (MTG) process, due to its unique properties, ZSM-5 zeolite has a high selectivity over gasoline boiling range of hydrocarbons with a research octanenumber (RON) of 90–96, comparable to that of conventional gasoline[1, 2]. Generally, this zeolite synthesized by TPAOH (TPABr) as template which is expensive. Since it is placed at the intersection of channels after synthesis, it is necessary to burn in calcination step to activate the catalyst and open the cavities. Therefore, the use of cheaper templates will be appropriate[3]. In this study, we tried to use inexpensive Si and Al sources and cheaper template than TPAOH (TPABr) for synthesis of ZSM-5 zeolite and investigate the catalytic performance of this catalyst in MTG process. ZSM-5 zeolite were synthesized via SiO2/Al2O3=50 using n-propylamine with a linear carbon chain as the single template, where no secondary template and additives were added. The Si and Al sources were sodium silicate solution and aluminum sulphate-18-hydrate, respectively. The obtained zeolite characterized by FT-IR, XRD and XRF techniques which approved that zeolite was synthesized correctly and with desired SiO2/Al2O3 ratio. The MTG experiment was carried out in a fixed-bed reactor under the operating conditions of T=380 °C, P=10bar and whsv=2h-1. Synthesized zeolite exhibited high catalytic activity (100%) during 5h of operating and significant selectivity to the aromatics (44.5%).