Preparation of preoxidated polyacrylonitrile fiber film supported SO_4~(2-)/TiO_2 catalyst and its catalytic performance

SO42-/ Ti O2 catalyst was firstly immobilized in preoxidated polyacrylonitrile by electrospinning and preoxidation. This novel catalyst was characterized by SEM,SEM-EDS,FT-IR and XRD. The results showed that the fiber structure was well kept after preoxidation and the Ti element was dispersed homogeneously in the fiber. Moreover,the polyacrylonitrile linear structure was changed into conjugate structure after preoxidation process. The catalytic performance of this fiber catalyst was evaluated by the acetalization reactions. The results showed that the fiber catalyst was very efficient for the acetalization reaction with high yields( 87%). Moreover,the catalyst can be easily recovered and reused for five times without obvious loss of initial activity. The high activity and stability made the fiber solid acid hold great potential for the green chemical processes.