Photocatalytic decomposition of bisphenol A in water using composite TiO₂-zeolite sheets prepared by a papermaking technique

Titanium dioxide (TiO₂) photocatalyst and zeolite adsorbent were made into a paper-like composite by a papermaking technique using pulp and ceramic fibers as sheet matrix. The photocatalytic performance for the degradation of bisphenol A (BPA) dissolved in water was investigated under UV irradiation. The TiO₂ sheet prepared was easier to handle than the original TiO₂ powders in aqueous media. The TiO₂ sheet could decompose the BPA under UV irradiation, although at a lower degradation efficiency than the TiO₂ suspension. The TiO₂-free zeolite sheet could not remove the BPA from water completely because of its adsorption equilibrium. Furthermore, the composite TiO₂-zeolite sheets exhibited a higher efficiency for BPA removal than the zeolite-free TiO₂ sheets, the efficiency of the former being equivalent to that of the TiO₂ suspension. The enhancement in removal efficiency was not attributed to the simple adsorption of BPA on zeolite but rather to the synergistic effect obtained through the combined use of TiO₂ photocatalyst and zeolite adsorbent in the paperlike composite sheet, which is believed to accelerate the BPA photodegradation in water.