Gasoline production via methaforming process using modified and shaped Zn/ZSM-5 zeolite

Abstract

Practically, the catalytic transformation of gas condensate to obtain gasoline products is a viable approach nowadays. This study deals with a process called methaforming in which gas condensate (obtained from Basra gas field- Iraq) coupled with ethanol as a co-feed under a nitrogen environment. The process was made possible with aid of using a metallic heterogeneous catalyst in the form of Zn/ZSM-5. Five catalysts were prepared and tested in this work, ZSM-5 (reference, pressed and shaped Si/Ai (80)), P–Zn/ZSM-5(R 80) pressed shaped, P–Zn/ZSM-5(R 30) pressed shaped, B–Zn/ZSM-5(R 80) bentonite mixed, and B–Zn/ZSM-5(R 30) bentonite mixed, at 2 wt% of Zn. The R 30 and R 80 represent two levels of acidity (Si/Al ratios: 30 and 80). Catalyst modification was conducted in two ways one using bentonite and polyvinyl alcohol (PVA). The second method is to shape the Zn/ZSM-5 by electromechanical pressing without bentonite. The methaforming was implemented at a pilot plant scale under certain conditions (T: 360–420 °C, P: 5 bar, and LHSV 1.2–2 h−1). The XRD and SEM characterizations have shown the modified catalysts maintain their main crystallinity and no obvious distortion in the crystal morphology post-metal impregnation. N2-adsorption isotherms demonstrate the catalyst is microporous. The outcomes have revealed better effectiveness observed in P–Zn/ZSM-5(R80). The research octane number (RON) has increased from 60.5 to 89.0, while P–Zn/ZSM-5(R30) and P-ZSM-5(R80) results show RON improvement from 60.5 to 80.1 and 82.0, respectively. Gas Chromatography (GC) has indicated there is an enhancement in aromatics and iso-paraffin from 7.4 to 14 and 35.9 to 47.4, respectively. In addition, the yield is reported as 75% under superior performance P–Zn/ZSM-5(R80) catalyst.

Keywords

• Methaforming process
• Gas condensate conversion
• Binder
• Si/Al ratio
• Octane number