Synthesis and characterization of H-ZSM-5 catalyst and its application for dehydration of methanol to dimethyl ether

A series of highly crystalline H-ZSM-5 zeolites with different SiO2/Al2O3 mole ratios ranging from 25 to 250 have been synthesized using hydrothermal crystallization method. The effects of Si/Al various ratios have been investigated on purpose to determine an optimum one. Dehydration of methanol to dimethyl ether on H-ZSM-5 catalysts was studied in fixed-bed flow reactor at a temperature of 573 K, pressure of 16 bar, and a LHSV of 26.5 h-1. The catalysts have been characterized using BET, XRD, NH3-TPD, ICP, TGA/DTA, TPH and SEM. According to the experimental results, catalytic activity and surface acidity was increased with an increase in silica/alumina ratio up to mole ratio of 125, andafter decrease. The sample with SiO2/Al2O3 mole ratio of 125 [H-ZSM-5(125)] has exhibited the best conversion and highest activity at methanol dehydration to DME.

کلیدواژه ها:

Methanol dehydration ، Dimethyl ether (DME) ، H-ZSM-5 Zeolite ، Hydrothermal method