Low Molecular Weight Biobased Aromatics from Pyrolysis Liquids Using Zeolites: Yield Improvements by Using Pyrolysis...

Area of Science:

• Biomass conversion
• Catalysis
• Green chemistry

Background:

• Pyrolysis liquids from lignocellulosic biomass are a potential source for aromatic compounds like benzene, toluene, and xylenes (BTX).
• Catalytic upgrading with zeolites is a promising method for converting these liquids into valuable chemicals.
• Optimizing the feedstock is crucial for efficient BTX synthesis.

Purpose of the Study:

• To experimentally determine the most suitable pyrolysis oil fraction for benzene, toluene, and xylenes (BTX) synthesis.
• To investigate the correlation between the chemical composition of different pyrolysis oil fractions and their BTX yield.
• To support the development of pyrolysis biorefineries for producing biobased chemicals and biofuels.

Main Methods:

• Fractionation of pyrolysis liquid into four distinct fractions using extraction and distillation.
• Detailed chemical characterization of each fraction using techniques like NMR, GC-MS, and GPC.
• Catalytic conversion experiments using a tandem microreactor with H-ZSM-5 zeolite catalyst.

Main Results:

• The highest BTX yield of 24% was achieved using fractions enriched in phenolic compounds.
• Other fractions yielded significantly lower BTX amounts, ranging from 4.4% to 9%.
• Established correlations between feedstock composition and BTX production efficiency.

Conclusions:

• Feedstock fractionation is essential for maximizing BTX yields from pyrolysis liquids.
• Phenolic-rich fractions are ideal for BTX synthesis via catalytic upgrading.
• Findings validate the pyrolysis biorefinery concept for targeted production of biobased chemicals.