New photocatalytic contactors obtained by PECVD deposition of TiO2 thin layers on the surface of macroporous supports

Two different kinds of PECVD anatase-based composite membranes have been successfully prepared by PECVD synthesis (at 150 A degrees C)/post-annealing (at 300 A degrees C) of a titania film deposited on macroporous supports as a top-layer or a skin-coverage. Photocatalytic activity of PECVD anatase films has been proved performing Pilkington test and methylene blue degradation determination in a lab-scale diffusion cell. Measurements of methylene blue degradation and water flow in a pilot-scale dynamic unit have enabled to show the performance of PECVD anatase-based membranes in terms of permeation and photocatalytic properties. Whereas bi-layered membranes present higher photo-degradation ability (up to 2.5 x 10(-8) mol s(-1) m(-2) destroyed methylene blue moles per unit of time and of membrane surface area), skin-covered membranes are characterized by higher water permeance (up to 6800 L h(-1) m(-2) bar(-1)). So both kinds of membranes should have an interest as photocatalytic contactors.