The degradation efficiency was under UV light in 120 min and it was 100% under solar light in 60 min. The reaction kinetic of photodegradation of caffeine was studied by firstorder kinetic model and the reusability of the ZnO sample was investigated through five cyclic tests. | Journal of Science & Technology 126 (2018) 016-020 Preparation of Flower-like ZnO Architecture for Photodegradation of Caffeine in Aqueous Solution Le Thi Mai, Nguyen Thi Men, Vu Anh Tuan* Hanoi University of Science and Technology – No. 1, Dai Co Viet Str., Hai Ba Trung, Ha Noi, Viet Nam Received: August 10, 2017; Accepted: May 25, 2018 Abstract The flower-like ZnO architecture was prepared by hydrothermal method. As-synthesized samples were characterized by XRD, SEM, and N2 adsorption/desorption isotherm. The composition of samples before and after calcination was analyzed by XRD, the precursor was completely transformed to ZnO at 400 °C. The catalytic performance of ZnO was evaluated by the degradation of caffeine in aqueous solution under different irradiation of lights. The degradation efficiency was under UV light in 120 min and it was 100% under solar light in 60 min. The reaction kinetic of photodegradation of caffeine was studied by firstorder kinetic model and the reusability of the ZnO sample was investigated through five cyclic tests. Keywords: ZnO, Caffeine, Photocatalyst, Flower-like structure, First-order kinetic chemicals, has serious implications for organisms and humans [5]. Therefore, removal of caffeine from effluents is very necessary. Pharmaceutical and personal care products (PPCPs) are increasingly important to our lives. However, they are classified as the most serious pollutants when discharged into the environment. Their presence in surface water pollutes the water environment and adversely effects on human health. Therefore, the treatment of PPCPs before emitting into environment has attracted the attention of many scientific researchers in the Global [1,2]. Photocatalysis is an environmentally friendly method for water and wastewater treatment. The main advantage of advance oxidation process by photocatalyst is the mineralization of organic pollutants into CO2, H2O and simple inorganic acids [3,6]. There are .
