Synthesis of dimethyl ether from syngas obtained by coal gasification

The characteristics of a tubular fixed-bed reactor for the direct synthesis of dimethyl ether (DME) from syngas obtained by coal gasification have been developed. DME synthesis test was conducted with a hybrid DME synthesis catalyst (CuO/ZnO/Al₂O₃ for methanol forming, γ-alumina for methanol dehydration) to understand the performance under the conditions of 6.0MPa, 260°C and GHSV=3,000 l/kg-cat·h. The H₂ conversion and CO conversion were 85-92%, 37-45%, respectively. About 68-80% of DME selectivity was observed. DME synthesis reactor also operated at the productivity of 4.6-4.9 mol/kg-cat·h, which is slightly higher than that in the Peng’s prediction results in case of H₂ : CO=0.5.