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

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: 1.5 bar; 175-325 degrees C; space time, 0.5-10 g(catalyst) h (mol(C))(-1); butene partial pressure, 0.375-1.5 bar; time on stream, 10 h. Results were evaluated with the aim of boosting naphtha (C-5-C-12(=)) 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 degrees C and 6 gcatalyst h (molC)(-1), where 23% corresponds to C-8-C-12(=) and 19% to C-5-C-7(=), respectively. Furthermore, the hierarchical porous structure facilitated catalysts to tend to a pseudo-stationary deactivation state after 2-3 h time on stream, which could be interesting for process scale up. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.