Fig. 1. MTA catalytic results for H-ZSM-5 exchanged with metal ions including Fe, Cu, Zn and Ag. Liquid methanol with a flow rate of 0.016 mL min⁻¹ was pumped into a fixed bed stainless steel reactor that hosted 0.5 g of the ion-exchanged catalysts sandwiched by quartz wool plugs. The carrier gas was N₂ with a feed rate of 3 mL min⁻¹ at reaction conditions of 397 °C and 10 bar. The conversion and selectivity are taken at steady-state, and the total selectivity with respect to converted methanol to all these products is 100%; measurement errors by gas chromatography are within 10%.