Efficient removal of thiophenic sulfides from fuel by micro-mesoporous 2-hydroxypropyl-β-cyclodextrin polymers through synergistic effect

Efficient removal of thiophenic sulfides is important for the purification of fuel. Herein, 2-hydroxypropyl- β -cyclodextrin polymers (2-HP- β -CDPs) with micro-mesopores are synthesized using 2-HP- β -CD and tetrafluoroterephthalonitrile (TFTPN) for removing thiophenic sulfides. The cross-linking of 2-HP- β -CD and TFTPN units forms the mesopores, and the cyclodextrin cavity acts as the micropores. The 2-HP- β -CDP 1:4 (1:4 is the molar ratio of 2-HP- β -CD and TFTPN in preparation) possesses a surface area of 197.49 m 2 g –1 , and most of pores are at 1.09 nm of micropores and 6.06 nm of mesopores. The synergistic effect of the micro-mesopores promotes 2-HP- β -CDP 1:4 to remove the thiophenic sulfides in the order of benzo[ b ]thiophene > 4,6-dimethyldibenzothiophene ≈ dibenzothiophene > thiophene. The removal efficiency and rate using 2-HP- β -CDP 1:4 are better than those of CD-based and most traditional adsorbents that have been reported. Most of sulfides adsorbed by mesopores diffuse rapidly to micropores from the wide end of cyclodextrin and then are selectively captured by the cyclodextrin units in 2-HP- β -CDP 1:4 . These findings can guide the synthesis of CD-based polymers and the application of fuel purification.