Photocatalytic degradation of phenol using silica SBA-16 supported TiO2

Abstract

Silica SBA-16, an efficient photocatalyst support with cubic (bottle-ink) mesoporous structure, large specific surface area, large pore volume and uniform pore size and titanium oxide (TiO2), a semiconductor compound as the active site were synthesized facilely via one-pot method and photocatalysts denoted as x%TiO2/SBA-16 where x = 2, 5, 10 and 20, in order to examine their photocatalytic ability for phenol degradation in different experimental conditions such as different phenol concentration in water (ppm), various pH of the solution and amount of applied photocatalyst (g/l). In order to confirm the correct structure of the SBA-16 support and prepared photocatalysts, various types of characterization analyses such as N2 adsorption/desorption, X-ray diffraction (XRD), TEM, SEM–EDX, UV–VIS and FT-IR were applied. Based on the employed analyses, it can be claimed that the SBA-16 support and synthesized photocatalysts demonstrated mesoporous structures with cubic pores that are in agreement with reliable literature. After carrying out all of the experimental factors for the phenol degradation process, it was found that the 10%TiO2/SBA-16 photocatalyst in the specific experimental conditions including pH 7, phenol concentration of 100 ppm and 1 g/l photocatalyst dosage achieved the highest performance which was approximately 90% degradation of phenol. Hence these mentioned conditions were chosen as the optimum experimental conditions. COD and TOC tests were employed to study the final products of the process and their results showed that the 10%TiO2/SBA-16 photocatalyst was able to reduce the COD and TOC of phenol solution up to 80% and 85%, respectively, means that the major amount of phenol converted to water and CO2 that are the final products of phenol degradation process.