Preparation and photocatalytic performances of sodium alginate/aluminum fumarate/TiO2 amorphous composite

In this study, a novel composite SA/AlFu/TiO 2 was successfully prepared as a promising adsorbent-photocatalyst for pollutants in wastewater based on aluminum fumarate (AlFu), titanium dioxide (TiO 2 ) and sodium alginate (SA) by the sol–gel method. The crystallinity and structure of the prepared composites were characterized by XRD, SEM, EDS, TEM and Raman. The results showed that the TiO 2 unit in SA/AlFu/TiO 2 was mainly in the amorphous phase. The adsorption and photocatalytic performance of SA/AlFu/TiO 2 were evaluated by the photodegradation of methyl orange (MO) under UV light irradiation. The composite SA/AlFu/TiO 2 has good adsorption capacity and high photocatalytic activity on MO. The influence of the dosage of AlFu or titanium precursor on the photodegradation of SA/AlFu/TiO 2 were discussed. The results showed that the role of AlFu was not only to be used as carrier of the TiO 2 unit but also to increase the photodegradation activity of the amorphous TiO 2 in SA/AlFu/TiO 2 . SA/AlFu/TiO 2 prepared with 0.5% AlFu and 4 mL tetrabutyl titanate showed the best removal rate of MO with 96.0% after 75 min. The photocatalytic degradation of amorphous SA/AlFu/TiO 2 on MO under UV light irradiation followed the combined adsorption/photocatalytic mechanism. The photocatalytic mechanism also demonstrated that ·O 2− is the main oxidation-active species in the photocatalytic process.