Catalytic Decomposition of Pyrolysis Fuel Oil over in Situ Carbon-Coated Ferrierite Zeolite for Selective Hydrogen Production

Abstract

Catalytic decomposition of pyrolysis fuel oils (PFO) for selective production of hydrogen without any significant formation of greenhouse gas (CO2 and CH4) was investigated using ferrierite (FER) zeolites with different Si/Al molar ratios. The hydrogen production rate based on the feed moles of PFO was maximized on the FER having a Si/Al molar ratio of 10.4, and the hydrogen production rate on the FER zeolites was well correlated with their amounts of strong acid sites which easily form the active coke intermediates. In situ generated crystalline coke precursors on the acidic FER(10) surfaces having larger amounts of defect sites further played an important role as catalytic active sites for PFO decomposition and reforming reaction of CH4 generated as a main byproduct. The crystalline phases of the encapsulated graphitic carbon layers formed on the outer surfaces of the FER zeolites were strongly affected by their original acidic strengths, which simultaneously altered a steady-state hydrogen production r...