Selective conversion of furans to p ‐xylene with surface‐modified zeolites

BACKGROUND: Owing to the growing consumption of oil and the negative environmental impacts, the production of p‐xylene (PX) from renewable biomass has gained significant attention recently. However, the major challenge for the production of PX from biomass or furans is how to improve the yield and selectivity of PX, along with reducing coke. RESULTS: The para selectivity in the catalytic conversion of furans was greatly enhanced owing to the deactivation of external surface and the adjustment of pore entrance. Co‐catalytic conversion of furans and methanol significantly enhanced the production of PX by the Diels–Alder reactions between furans and olefins and the alkylation of benzene/toluene with methanol. The highest PX yield of 17.8 C‐mol% with a p‐xylene/xylene ratio of 94.5% was obtained by the co‐conversion of 2‐methylfuran with methanol over the 15%La/10%Ce/HZ catalyst. CONCLUSION: This work proved that furans (2‐methylfuran, 2,5‐dimethylfuran, furfural and furan) were able to be selectively converted into a high‐value chemical (PX) over the 15%La/10%Ce/HZ catalyst. The transformation mainly involved four key reactions: the catalytic cracking of furans, the Diels–Alder reactions, the alkylation of aromatics and the isomerization of xylenes over the surface‐modified zeolite. © 2019 Society of Chemical Industry