A High Yield Synthesis Fe۳O۴/TiO۲/GQDs Nanocomposite for Photodegradation of Imipramine from Wastewater

The pharmaceutical wastewater includes significant amounts of toxic pollutants that needs totreatm ent by using advanced methods. In this study, the photocatalytic degradation of imipramine inaquatic media was investigated by the prepared photocatalyst magnetite titanium dioxide loaded bygraphene quantum dots (Fe۳O۴/TiO۲/GQDs). Firstly, photocatalyst Fe۳O۴/TiO۲/GQDs synthesized in foursteps which included co-precipitation, sol-gel, and hydrothermal methods for preparation of Fe۳O۴, TiO۲,GQDs, and nanocomposite, respectively. Then, the morphological, and structural properties and qualityof the nanocomposite were investigated using different methods comprising XRD, SEM, BET, and TEM.Finally, the efficiency of photocatalytic degradation was examined to obtain optimum parameters thateffected on pgotocatalyst application. The diffraction peaks of XRD data were accordance with the Fe asmagnetite, Ti as anatase and graphene quantum dots formation. SEM and TEM analysis of the preparednanocomposite indicated the spherical and size of particles. BET results showed mesoporous structurewith desired characteristic. Then, the effect of different variables showed photocatalyst dose of ۰.۵ g/l, pH≈۳, temperature ≈۴۰ °C for ۱۲۰ minutes under UVA irradiation source (۹W) were optimized condition.The maximum removal efficiency from real effluent was about ۷۰% in optimum. Also, the resultsobtained the major degradation mechanism of imipramine was direct oxidative decomposition through thephotogenerated holes. The kinetic study of reactions indicated, the photocatalytic decomposition ofimipramine followed by the apparent first-order models under the UVA light irradiation. The results showthe synthesized photocatalysts Fe۳O۴/TiO۲/GQDs can be applied in the treatment of industrial effluentscontaining persistence organic pollutants under optimal conditions.