Analysis and photocatalytic degradation of methylene blue dye using a natural photosensitizer from Ruta extracts and UV-Vis spectrometry

Water treatment using sustainable methods is currently a major focus for researchers. In this context, the presented study explores an eco-friendly approach for removing harmful dyes from wastewater by utilizing extracts from the leaves of Ruta Montana L. and Ruta Chalepensis L. for the photodegradation of dye-contaminated water. The photo-catalytic performance of the obtained extracts and the pure xanthotoxin isolated from these extracts was investigated for methylene blue elimination using the photo-degradation process followed by UV-Vis spectroscopy. This method combines the power of sunlight with plant-derived photo-catalysts, especially furocoumarins known for their photochemical properties. The results of the UV-Vis measurement showed that the Ruta chalepensis extract exhibited better photo-degradation performance (۲۴%) than Ruta montana extract (۱۸%) at a concentration of ۲۰ mg L-۱. In comparison, the pure xanthotoxin, the active ingredient, showed an interesting photo-degradation of dye (۳۳%); this efficiency increases with increasing extract dose. The use of the Xanthotoxin/ZnO hetero system caused an improvement of the photo-degradation ability to ۹۱%. These results were confirmed by the study of the kinetics of the dye degradation, where the hetero system Xanthotoxin/ZnO represents the highest values of the rate constant (k) and the correlation coefficients (R۲). Also, the xanthotoxin can be separated from the wastewater mixture by centrifugation, and spectroscopic analysis showed that the photo-degradation process did not alter the molecule.

کلیدواژه ها:

UV-Vis spectroscopy ، Methylene blue ، ZnO ، Ruta montana and chalepensis L ، Photo-degradation ، Furocoumarins