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

In this study, a novel composite SA/AlFu/TiO2 was successfully prepared as a promising adsorbent-photocatalyst for pollutants in wastewater based on aluminum fumarate (AlFu), titanium dioxide (TiO2) 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 TiO2 unit in SA/AlFu/TiO2 was mainly in the amorphous phase. The adsorption and photocatalytic performance of SA/AlFu/TiO2 were evaluated by the photodegradation of methyl orange (MO) under UV light irradiation. The composite SA/AlFu/TiO2 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/TiO2 were discussed. The results showed that the role of AlFu was not only to be used as carrier of the TiO2 unit but also to increase the photodegradation activity of the amorphous TiO2 in SA/AlFu/TiO2. SA/AlFu/TiO2 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/TiO2 on MO under UV light irradiation followed the combined adsorption/photocatalytic mechanism. The photocatalytic mechanism also demonstrated that center dot O2- is the main oxidation-active species in the photocatalytic process.

Automated summary

In this study, a novel composite SA/AlFu/TiO2 was prepared for adsorption and photocatalytic degradation of pollutants. The characteristics of the composite were analyzed by various techniques. The composite showed good adsorption capacity and high photocatalytic activity. The role of AlFu in the composite was discussed. The best removal rate of pollutants was achieved with a specific dosage of AlFu and tetrabutyl titanate. The photocatalytic degradation followed a combined adsorption/photocatalytic mechanism.