One-Step Conversion of n-Butanol to Aromatics-free Gasoline over the HZSM-5 Catalyst: Effect of Pressure, Catalyst Deactivation, and Fuel Properties as a Gasoline

[Image: see text] Sustainable production of gasoline-range hydrocarbon fuels from biomass is critical in evading the upgradation of combustion engine infrastructures. The present work focuses on the selective transformation of n-butanol to gasoline-range hydrocarbons free from aromatics in a single step. Conversion of n-butanol was carried out in a down-flow fixed-bed reactor with the capability to operate at high pressures using the HZSM-5 catalyst. The selective transformation of n-butanol was carried out for a wide range of temperatures (523–563 K), pressures (1–40 bar), and weight hourly space velocities (0.75–14.96 h(–1)) to obtain the optimum operating conditions for the maximum yields of gasoline range (C(5)–C(12)) hydrocarbons. A C(5)–C(12) hydrocarbons selectivity of ∼80% was achieved, with ∼11% and 9% selectivity to C(3)–C(4) paraffin and C(3)–C(4) olefins, respectively, under optimum operating conditions of 543 K, 0.75 h(–1), and 20 bar. The hydrocarbon (C(5)–C(12)) product mixture was free from aromatics and primarily olefinic in nature. The distribution of these C(5)–C(12) hydrocarbons depends strongly on the reaction pressure, temperature, and WHSV. These olefins were further hydrogenated to paraffins using a Ni/SiO(2) catalyst. The fuel properties and distillation characteristics of virgin and hydrogenated hydrocarbons were evaluated and compared with those of gasoline to understand their suitability as a transportation fuel in an unmodified combustion engine. The present work further delineates the catalyst stability study for a long time-on-stream (TOS) and extensive characterization of spent catalysts to understand the nature of catalyst deactivation.