Sol-gel membrane modification for enhanced photocatalytic activity

Novel Submerged Photocatalytic Membrane Reactor for Treatment of Olive Mill Wastewaters

“…All the tests with the control and the photocatalytic membranes were performed with the same membrane to allow a reliable comparison between the different assays performed. In a previous study [31], the chemical stability (absence of titanium release) of the modified membranes was verified after filtration with different cleaning solutions at 65 ± 5 • C: distilled water, citric acid 2% (w/v) and NaOH 4% (w/v) whereas the reproducibility of the membranes was confirmed after five different degradation tests of methylene blue using two different commercial batches. In all the filtration tests, a permeability decrease was observed throughout the entire experimental time (Figure 3).…”

“…All the tests with the control and the photocatalytic membranes were performed with the same membrane to allow a reliable comparison between the different assays performed. In a previous study [31], the chemical stability (absence of titanium release) of the modified membranes was verified after filtration with different cleaning solutions at A value of transmembrane pressure of 0.2 bar was chosen since it was the highest transmembrane pressure value assuring the linearity between the transmembrane pressure and the permeate flux.…”

“…All solvents employed were of reagent-grade quality and used without further purification. The modification protocol followed (labelled as SGSi-D (L 3 )) was previously optimized and detailed by Huertas et al [31]. Briefly, the concentration of Degussa TiO 2 nanoparticles used was 0.05 M and the molar ratio between TiO 2 and SiO 2 was 1:0.9.…”

“…Briefly, the concentration of Degussa TiO 2 nanoparticles used was 0.05 M and the molar ratio between TiO 2 and SiO 2 was 1:0.9. The control and modified membrane were previously characterized [31]. Compared to the control, the modified membrane had a higher number of pores, a higher pore density (2.5 ± 0.2 µm −2 ), a lower porosity of 0.9% and lower average Feret diameter (longest distance between two points along the selection boundary) of 91 ± 8 nm.…”

“…In a previous work, an extremely promising and reproducible photocatalytic activity was reported when silicon carbide surfaces were modified with TiO 2 obtained by the sol-gel process, using Degussa P25 and silicon carbide nanoparticles [31].…”