Photocatalytic Decolourization of Rhodamine B by Modified Photo-Fenton Process with Quasicrystals – Preliminary Research

A novel photocatalytic process using a modification of photo-Fenton reaction, with sodium percarbonate (SP), as an alternative source of H₂O₂, and alloy Al₆₅Cu₂₀Fe₁₅ containing, among others, quasicrystals (of the percentage composition Al₆₅Cu₂₀Fe₁₅), being a source of iron ions, effectively decolourizes the aqueous solution of rhodamine B (RB; solution of 5 mg/l). The source of UV radiation was a lamp with a power of 36 W. The experiments were carried out at pH = 7 and reaction time (from 5 to 60 min). The increase in SP concentration (in the range of 8.3 to 33.3 g/l) significantly increased the degree of degradation of RB and the reaction rate. However, the use of quasicrystals, in the range of 8.3 to 33.3 g/l, was also important in the modified photocatalytic photo-Fenton process. The best degradation effects of RB (95%) were obtained for the highest SP concentration of 33.3 g/l and the lowest quasicrystal concentration of 8.3 g/l. On the other hand, visual decolourization of RB was obtained with an efficiency of 70% for SP and quasicrystal concentrations of 16.7 g/l and 16.7 g/l, respectively, after 45 minutes, and for SP and quasicrystal concentrations of 33.3 g/l and 8.3 g/l, respectively, after the time of 20 minutes. The best RB degradation effects in the comparative method (UV/Na₂CO₃·1.5H₂O₂ without the addition of quasicrystals) were only 52.7%. The obtained results encourage further research to optimize the conditions of the proposed method and to investigate its applicability to other types of dyes and pollutants.