Solar photocatalytic degradation of commercial textile azo dyes: Performance of pilot plant scale thin film fixed-bed reactor

摘要

Performances of solar photocatalytic pilot plant using Ti02-P25 (Degussa) were investigated for removal of commercial azo dye chosen as model compound. Experiments were carried out to optimize various parameters, influencing the performance of the operated thin-film fixed-bed reactor (TFFBR) with an area of 25 m~2. The results showed kinetic dependency on flow rate, catalyst loading, and initial dye concentration. The best discoloration rate was obtained at the optimum flow rate of 3 m~3/h. Increasing catalyst loading density up to 10 g/m~2, does not lead to high improvement of the discoloration rate. The photocatalytic degradation kinetic of TOC is discussed in terms of Langmuir-Hinshelwood model. Initial mineralization rate expressed by mg kJ~(-1) reach a maximum value at initial TOC closed to 30 mg/L.