Facile Synthesis of Highly Active Sulfated Titania Nanofibers for Viscous Acid-Catalytic Reactions.

Well-shaped sulfated titania nanofibers were prepared by impregnation of hydrogen titanate with (NH4)2S2O8 and calcination. Various characterization results showed that sulfated titania nanofibers consisted of smooth-surface and long-size fibers with the diameter of dozens of nanometers. Moreover, acid characteristics of sulfated titania nanofibers exhibited the high acid content, multi-strength acid sites and large Brønsted/Lewis acid ratio. In low-viscosity esterification, sulfated titania nanofibers had 1.2 ~ 2.1 times the reaction rate of other sulfated titania and other typical solid acids. Simultaneously, sulfated titania nanofibers possessed the higher DS value of product than those by other solid acids in highly viscous cellulose acetylation (2.41 versus 2.06 ~ 2.21). Besides these, sulfated titania nanofibers could show the excellent recycling performance in viscous acid-catalytic reactions. [ABSTRACT FROM AUTHOR]