Catalytic conversion of waste particle board and polypropylene over H-beta and HY zeolites

The catalytic copyrolysis of waste particle board (WPB) and polypropylene (PP) was investigated for the first time over HY (5.1), HY (30), H-Beta and Ga/H-Beta catalysts. The catalysts were characterized by BET and NH₃-TPD analyses. The catalytic pyrolysis of the WPB increased the production of gas products (CO, CO₂, C₁-C₄) compared to non-catalytic pyrolysis. Acids and levoglucosan, which are the main components of bio-oil produced from non-catalytic pyrolysis, were converted to more valuable aromatics, phenolics, and furans through dehydration, deoxygenation and aromatization. The most abundant products from the copyrolysis of WPB and PP were large-molecular-mass hydrocarbons (≥C₁₀). However, catalytic copyrolysis increased the yields of small-molecular-mass hydrocarbons in the gasoline range, aromatics and phenolics. The water content in bio-oil was reduced significantly by copyrolysis with PP, contributing to the improvement in oil quality. HY (5.1) with the largest number of acid sites showed higher catalytic activity than HY (30) and H-Beta because the decomposition and reforming reactions during catalytic copyrolysis occurred on the acid sites of the catalysts. Ga/H-Beta showed even higher selectivity toward the aromatics than H-Beta despite the smaller quantity of acid sites, suggesting that Ga promoted the dehydrocyclization of the reaction intermediates.