Background and Aim: Endocrine Disrupting Chemicals (EDCs), and potential EDCs are mostly man-made, found in various materials such as pesticides, metals, additives or contaminants in food, and personal care products. Phthalates are a group of these compounds that are carcinogenic to animals and can cause fetal death and congenital anomalies. The aim of this study was to investigate the photocatalytic process using GO/ZnO nanocomposites under LED irradiation for removal of Endocrine Disrupting Chemicals (EDCs) from aqueous solutions.
Materials and Methods: In this study, GO/ZnO nanorods were characterized by, Field emission scanning electron microscopy, transmission electron microscope, and Brunauer–Emmett–Teller surface area analysis. A Central Composite Design was used to optimize the reaction parameters for the removal of DEP by GO/ZnO. The four main reaction parameters optimized in this study were the following: the LED radiation time, pH, and the initial concentration of phthalates and the concentration of ZnO and graphene-oxide. The interaction between the four parameters was studied and modeled using the Design Expert 10 software. Phthalate detected by HPLC apparatus equipped with a UV detector at 225 nm wavelength with methanol (90%) and Acetonitrile (10%) phases.
Results: The results of FE-SEM and TEM showed that the ZnO is composed of a bar and separate face. Based on the peak obtained, the diameter and length of the nanorods are 20-60 and 200 nm respectively. A maximum reduction of 90% of DEP was achieved at pH 5 and 120 minutes. The results represent the prediction of a model fitted from the Quadratic model (p-value<00001).
Conclusion: The interaction of variables showed that the maximum effect was belonged to the pH and the time in the process reactions. Also, the results showed that the GO/ZnO low power LED irradiation can be used as an effective method for the removal of EDCs from environmental.

Background and Aim: Styrene monomer is a volatile organic compound that is used extensively in the manufacture of plastics, rubber, and resins. Many health effects caused by continuous exposure to styrene have been reported by different organizations of health and safety. This study was carried out to determine the efficiency of photocatalytic removal of styrene by using zinc oxide nanoparticles immobilized on diatomite.
Materials and Methods: This study was done on a laboratory scale, in which zinc oxide nanoparticles with the size of 20 to 40 nm and 5% concentration were stabilized on the natural diatomite and then irradiated with UV light as a photocatalytic agent in order to degrade styrene vapors.
Results: In this study, the concentrations of 20, 100, and 300 ppm styrene were passed through a reactor containing diatomite substrate covered with nano-ZnO (MDi/ZnO 5%). The results showed that the bed of MDi/ZnO 5% could remove 35 percent of styrene vapors at concentrations of 20 ppm and a flow rate of 1 lit /min.
Conclusion: Due to the removal efficiency of 35% styrene vapors by MDi/ZnO 5% substrate and properties such as low cost and availability of diatomite and zinc oxide, it can be used from the bed to remove volatile organic compounds, but in comparison to similar studies with other beds such as natural and synthetic zeolites and activated carbon, it could not achieve the desired results in a photocatalytic activity for its application in industry. However, because of its abundance in the world and Iran, low cost of preparation, and also its unique characteristics, further studies are recommended about its modification and application in photocatalytic processes.