Parameters Affecting Methylene Blue Dye Photodegradation by Carbon dots Prepared from Olive Pomace

摘要

Olive pomace was used as a precursor in synthesizing CNDs through pyrolysis and oxidation. The photocatalytic activity of CNDs was evaluated for the degradation of methylene blue (M.B). dye under irradiation of a visible light source. The influence of various operational parameters such as the photo-catalyst dose, solution pH, the initial concentration of M.B. dye, NaCl salt content, visible light source power, and distance were investigated and their effects on degradation rate and efficiency have been estimated. The photocatalytic mechanism and kinetic reaction were studied to find that ROS is responsible for causing a -pseudo-first-order photodegradation of the targeted dye. It was found that both rate and efficiency increased linearly with increasing the photocatalyst dose (CNDs) spiked into M.B solution, along with a maximum degradation first-order rate of 0.061 min~(-1) obtained at pH = 10.6 with an efficiency of 92% after 120 minutes of light irradiation.