Industrial & Engineering Chemistry Research, Vol.53, No.14, 5709-5717, 2014
Visible Light Photodegradation of Rhodamine B Dye by Two Forms of Carbon-Covered Alumina Supported TiO2/Polysulfone Membranes
Two types of polysulfone (PS) membranes (one on a nonwoven fabric and the other without the fabric) with nanosized carbon-covered alumina supported TiO2 (CCA/TiO2) uniformly dispersed in 15 wt % PS casting solution were prepared. TiO2 nanoparticles were added in order to enhance the visible light photodegradation potential of the PS membranes. The influence of CCA/TiO2 nanoparticles on the PS membranes was investigated using Raman, XRD, SEM, TGA, and TGA-FTIR characterization, and their mechanical strength was determined with an Instron tensile tester. The Raman and XRD results exposed the probability of interactions between the polymer and the CCA/TiO2 nanoparticles, the SEM suggested that these membranes had a high degree of porosity, and this might have resulted in an increase in the permeate flux. The membranes were subsequently tested for the capability to photodegrade Rhodamine B under visible light illumination. The PS/CCA/TiO2 (with fabric) membrane photodegraded 82.4% of the dye, while the PS/CCA/TiO2 (without a fabric) membrane degraded 78.7% of Rhodamine B after 300 min. The photodegradation followed a pseudo-first-order reaction rate, and the apparent rates were 0.00579 and 0.00515 min(-1) for PS/CCA/TiO2 (with fabric) membrane and the PS/CCA/TiO2 (without a fabric), respectively. These results are promising in the quest to produce membranes with the added advantage of photodegrading pollutants under visible light.