Large scale production of photocatalytic TiO 2 coating for volatile organic compound (VOC) air remediation

Abstract

In this work, a pure TiO 2 colloid was produced at pilot scale of 5 L and deposited on stainless steel with a pilot roll-to-roll line to produce photocatalytic coating for VOC degradation. The pure TiO 2 colloid was synthesized with an aqueous sol-gel process, producing crystalline nanoparticles around 4-5 nm (mainly anatase phase) dispersed in water. The crystalline phases were produced at low temperature (<100 °C) without calcination step. The crystalline coating produced with roll-to-roll process was very thin, around 50 nm. The photoactivity of this coating towards VOC destruction was evaluated on the degradation of acetaldehyde; the measured activity of the coating was 35 ± 5%. With the use of mass spectrometer, it was shown that acetaldehyde was mainly converted in CO 2 . The durability of the coating was assessed after 1, 2 and 3 weeks, and showed that the photoactivity stayed constant for this period.