Preparation of Reusable Pva-Nano Tio2 Foam For Wastewater Treatment

Abstract

With increasing industrialization, rapid economic development, and an ever-growing population, the problem of water pollution and water scarcity is increasing at an alarming rate. It is estimated that more than 800,000 annual diarrheal deaths are attributed to unsafe water usage. Furthermore, traditional wastewater treatment technologies, such as adsorption, chlorination, and biochemical methods are difficult to utilize for treating wastewater at low concentration for they lead to high toxicity. However, Nano TiO2-based photocatalytic technology is a new highefficiency and energy-saving alternative because NanoTiO2 can degrade organic pollutants into non-toxic compounds such as CO2 and H2O under the sunlight. Nonetheless, separating and recycling Nano TiO2 from water remains to be a huge challenge. Therefore, we prepared PVA-Nano TiO2 foam at high speed stirring, film laying, drying, and thermal crosslinking to embed in PVA for reuse and recycle. The morphology, structure, and photocatalytic performance of PVA-Nano TiO2 foam were characterized in detail by SEM, TGA, FTIR, UV-Vis, and so on. The results show the cell size of the foam is about 0.2-0.5 mm, and the swelling degree of PVA-Nano TiO2 foam is about 600%. The TiO2 nanoparticles also have no effect on thermal crosslinking of PVA. Under sunlight, the PVA-Nano TiO2 foam possesses photocatalytic activity that is higher than that of non-porous PVANano TiO2 film due to the higher permeability of water and impurity with higher porosity. In addition, the PVANano TiO2 foam exhibits good reusability under multi-cycle use. Thus, this novel design of PVA-Nano TiO2 foam is simple, eco-friendly, and effective with potential practical application value.