Production of olefins from ethanol by Fe and/or P-modified H-ZSM-5 zeolite catalysts

BACKGROUND: Much attention has been paid to the catalytic conversion of ethanol to olefins, since biomass resources such as ethanol are carbon-neutral and renewable, and olefins are useful as both fuels and chemicals. It has been reported that zeolite H-ZSM-5 is effective for converting ethanol to hydrocarbons, with the chief products being aromatic compounds. RESULTS: Successive addition of Fe and P to the H-ZSM-5 improved the initial selectivity for propylene, while the sole addition of Fe or P and co-addition of Fe and P showed medium initial selectivity. In general, catalysts showing higher initial selectivity for propylene exhibited a steeper decrease in propylene selectivity with time on-stream. The cause of the change in product selectivity may be carbon deposition during reaction. Addition of Fe and P can improve catalytic stability when processing both neat and aqueous ethanol. The catalytic performance was regenerated by calcination in flowing air. CONCLUSION: Fe- and/or P-modified H-ZSM-5 zeolite catalysts efficiently produced olefins (especially propylene) from ethanol. Effective catalyst regeneration was achieved by calcination in flowing air. (C) 2010 Society of Chemical Industry