Behavior of the new composites obtained from fly ash and titanium dioxide in removing of the pollutants from wastewater

Abstract The goal of this paper was to develop a low-temperature TiO 2 -fly ash (TiO 2 -FA) composite based on interaction in alkaline solution using hydrothermal methods, to obtain crystalline nanocomposite at low temperature. These composites are interesting to be applied in visible photocatalysis/adsorption simultaneous advanced wastewater processes. Combining fly ash with titanium dioxide has the following advantages: (1) the titanium oxide crystallites grow on the support (active fly ash); (2) pollutant molecules migrate to the surface of TiO 2 can be degraded by photocatalysis; and (3) activated fly ash substrates are regenerated in situ. The composites were characterized by the scanning electron microscopy (SEM) and atomic force microscopy (AFM) for morphological characterization of the surface, X-ray diffraction (XRD) for phase and crystallinity analysis, UV–vis spectroscopy to calculate the energy band gap, surface analysis by determining the contact angle, porosity analysis (BET). The photocatalytic property of the composites was evaluated by dye (methylene blue), surfactant (dodecylbenzenesulfonate–SDBS) degradation under UV and Visible irradiation. The adsorption tests were made on heavy metal (Cu 2+ ) cation. Properties of composites were correlated with the adsorption/photocatalytic activity of the samples.