Catalytic fast pyrolysis aromatics selectivity

Based on results with HZSM-5, researchers have investigated the use of metal additives on HZSM-5 to improve aromatics production or tune selectivity. The Huber group has shown marked improvement with the use of gallium exchanged HZSM-5 for the catalytic fast pyrolysis of furans. In this report, the gallium should be incorporated by exchange rather than incipient wetness or framework substitution to... 

A high aromatics selectivity, however, requires proper catalyst selection. Zhang et al. studied the fast pyrolysis of corncob in absence and presence of a catalyst (ie, ZSM-5) [287]. The presence of the catalyst increased the yields of noncondensable gas, water, and coke, while decreasing the liquid and char yields. The catalyst induced a decrease of the oxygen content of the liquid fraction by more than 25%. These studies indicate the importance of a catalyst during biomass pyrolysis. The most important catalytic parameters affecting the product distribution are pore structure and acid site type. This was demonstrated by testing siUcalite, a material with the same pore structure as ZSM-5 but with intrinsic different acid sites, and siUca-alumina, an amorphous material with Brpnsted acid sites, in the catalytic pyrolysis of... 

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