Preparation of H-ZSM-5 Nano-Zeolite Using Mixed Template Method and its Activity Evaluation for ethanol to DME Reaction

H-ZSM-5 nano-zeolites were synthesized by hydrothermal method using tetrapropylammonium hydroxide (TPAOH) as a template in the presence of various TPABr concentrations. The effect of different TPABr/TPAOH molar ratios was studied on the catalytic performance of dehydration of methanol to dimethyl ether (DME) in a fixed bed reactor under the same operating conditions (T=300°C, P=1 atm, and WHSV=26 h−1). The prepared catalysts were characterized by XRD, SEM, BET and NH3-TPD. The characterization results showedthat the crystal sizes of the catalysts enlarge by increasing the concentration of TPABrin the synthesis reaction mixture. It was observed that H-form zeolite catalysts were active and selective for DME synthesis. These catalysts showed a high methanol conversion and also very high DME selectivity. It was found that by addition of up to 10 mole% TPABr in the synthesis reaction mixture, no significant effect was observed on the physical and chemical properties and catalytic activity of prepared catalysts.