【摘要】 在2个等压串联连续流动固定床反应器内考察了合成气经由二甲醚制取芳烃的反应性能。一段合成二甲醚反应采用Cu/Zn/Al2O3和γ-Al2O3复合催化剂;二段合成芳烃反应采用HZSM-5(Si/Al=38)催化剂。考察了反应压力对合成芳烃反应的影响,并分析了产物的分布规律。结果表明:在T1=270℃,T2=360℃,GHSV=500h-1条件下,反应压力由2MPa增加到4MPa时,芳烃选择性轻微降低,由86.75%降低到83.67%,同时CO转化率从72.47%升高到84.34%,产物中均四甲苯的选择性增加不明显。而当压力增加到5MPa时,芳烃选择性降低到63.51%,而异构烷烃选择性提高5倍多。反应压力增加,反应平衡倾向于加氢异构化反应;反应压力在2～4MPa时,有利于芳烃的合成。更多还原

【Abstract】 The synthesis of aromatics from syngas via dimethyl ether has been successfully carried out in the two flow type fixed-bed reactors in series under constant pressure.The first reactor contains the catalysts of Cu/Zn/Al2O3 and γ-Al2O3,HZSM-5 catalyst is loaded in the second reactor where oxygenated compounds (dimethyl ether) are converted into aromatics.The effect of reaction pressure is investigated.The result shows that the enhancement of reaction pressure from 2 MPa to 4 MPa leads to the decrease of aromatics selectivity from 86.75% to 83.67%,and the increase of CO conversion from 72.47% to 84.34%.However,1,2,4,5-tetramethylbenzene selectivity only gets little higher.When the reaction pressure is increased to 5 MPa,aromatics selectivity declines to 63.51%,whereas iso-paraffins selectivity undergoes an increase of more than fivefold concurrently.The reaction inclines to isomerization with the increase of reaction pressure,and it is benefit for the aromatics synthesis during 2-4 MPa of reaction pressure.更多还原