Low-pressure oligomerization of 1-butene to liquid fuels on HZSM-5 zeolite catalysts: Effect of operating conditions

Abstract

The capacity of HZSM-5 zeolite (SiO2/Al2O3 ratio=30–280) based catalysts with a hierarchical porous structure has been explored for the oligomerization of 1-butene at low pressure. Catalysts were characterized (structural, physical and acid properties) and tested in a fixed bed reactor under the following conditions: 1.5bar; 175–325°C; space time, 0.5–10gcatalysth(molC)−1; butene partial pressure, 0.375–1.5bar; time on stream, 10h. Results were evaluated with the aim of boosting naphtha (C5-C12=) fraction. A good compromise between conversion (62% in C units contained) and naphtha yield (42%) was achieved by using a HZSM-5 zeolite with SiO2/Al2O3=30 at 275°C and 6gcatalysth(molC)−1, where 23% corresponds to C8-C12= and 19% to C5-C7=, respectively. Furthermore, the hierarchical porous structure facilitated catalysts to tend to a pseudo-stationary deactivation state after 2–3h time on stream, which could be interesting for process scale up.