Photocatalytic Degradation of Aqueous Phenanthrene in a Slurry Photocatalytic Reactor:Optimization and Modelling

A photoreactor with 254 nm, 16 W UV lamp was evaluated for phenanthrene (PHE) degradation. The effect of operating variables such as initial PHE concentration (1000–1500 μg/l), catalyst dosage (0.1– 0.9 g/l) and pH (3.0–9.0) on PHE degradation was investigated in detail. The batch study of photocatalytic process showed 83.5% PHE degradation and 60.2% TOC removal for optimized values (PHE concentration – 1000 μg/l, TiO₂ dosage – 0.5 g/l and pH – 3.0) during 3 h reaction. The photocatalytic degradation of PHE was found to follow pseudo-first-order kinetics. The results obtained from continuous process revealed that nano TiO₂ could be used for industrial applications because of its potential for long-term operations. Response surface methodology (RSM) with Design Expert software was used to analyse the obtained experimental data.