جستجوی مقالات مرتبط با کلیدواژه « رودامین بی » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

Photocatalytic processes using solar energy are one of the new chemical purification methods in the purification of colored organic pollutants, attracting much attention. Graphite carbon nitride photocatalyst (g-C3N4) was synthesized using the thermal polymerization method and using (single or combined) melamine, thiourea, and ammonium chloride precursors. Synthesized photocatalysts based on g-C3N4 were analyzed to investigate their structure, morphology, and properties using XRD, FT-IR, SEM, EDX, BET, PL, and DRS analyses and to degrade the cationic dye Rhodamine B (RhB) used. The results of the experiments showed that the graphite carbon nitride synthesized with the combined precursor of melamine, thiourea, and ammonium chloride (MTA) with a dose of 0.2 g/l and a color concentration of 50 mg/l has the highest performance on the degradation of RhB color and after 2 hours, caused 100% decolorization of the dye solution. Also, the photocatalytic efficiency of MTA in the degradation of RhB dye was almost constant in five consecutive cycles. In addition, according to the results of the trapping experiments, the active species of superoxide radical (•O2-) was the dominant species for the degradation process of RhB. Hence, MTA can be considered an efficient catalyst due to its advantages, such as one-step synthesis, effective photocatalytic performance, and reusability.

In this work, effect of water content as dispersed phase of water/AOT/oil microemulsions on the droplet size and location of hydrophilic probe‎ of Rhodamine B (RhB) within microemulsion was studied by means of dynamic light scattering (DLS) and absorption spectroscopy. The dynamical characterization of micelles by DLS technique showed that by increasing the water content within AOT microemulsion containing dye with certain concentration, the droplet size increased and the interactions between nano-droplets were more attractive as a function of the mass fraction of nano-droplets (MFD). Study of the dye spectroscopy within microemulsion indicated that the changes in λmax of absorption of dye within AOT microemulsion decreased as W increased with MFD.  It was also observed that hydrophilic dye of Rhodamine B can be located near tail of AOT (Gouy Chapman Layer) of microemulsion in addition to the locating into the water/oil interface (Stern Layer) but not in water droplet. On the other hand, the number of formed AOT-RhB ion pair complex in the oil increased with decrease in content of water of within water/AOT/oil microemulsion.