Solar Photocatalytic Decontamination of Phenol Using Pyrolytic $TiO2$ Films Deposited Inside Glass Tubing

Solar photocatalytic degradation of phenol was performed using $TiO2$ films deposited inside glass tubing by a spray-gel technique. Photocatalytic phenol degradation experiments were performed using either solar radiation or a $300W$ lamp simulating the UVA solar radiation component. In order to concentrate the radiation a reflective surface was placed in the rear part of the tube. The obtained $TiO2$ films were amorphous, but after annealing at $450°C$ for $1h$⁠, the films crystallized to the anatase structure and presented photocatalytic activity. The films’ morphology, observed by scanning electron microscopy, presented a uniform film and agglomerates of $TiO2$⁠. The size of the agglomerates increases as Ti isopropoxide/ethanol molar ratio of the starting solution increases. The concentration of the precursor solution and the film thickness of $TiO2$ was optimized for phenol degradation. The $TiO2$ film obtained with a Ti-isopropoxide/ethanol molar ratio of 0.0259 and a film thickness between $1.2to2.4μm$ were shown to yield the highest phenol degradation.