Conversion of light fraction of green syncrude in production of synthetic aviation fuel

Upgrading green syncrude derived from lean-hydrogen syngas into jet fuel-range hydrocarbons requires addressing the challenges posed by oxygenate-rich light fraction. Produced via iron-based Fischer-Tropsch synthesis, this fraction contains alcohols, olefins, paraffins, and other oxygenates, which hinder efficient olefin oligomerization. Using a synthetic mixture mimicking syncrude, we evaluated the effect of oxygenates on ZSM-5 performance and demonstrated the necessity of a dehydration step prior to oligomerization. Pre-oligomerization dehydration enabled stable operation for 100 h, whereas residual oxygenates led to reduced ZSM-5 activity, a trend also observed with our syncrude. Increasing the dehydration temperature further enhanced catalyst stability, maintaining high reactivity for 180 h.