Degradation of direct red-81 and direct yellow-27 by photolysis with UV-light and solar irradiation using C-N-codoped TiO2

摘要

Direct Red-81 (C28H19N5Na2O8S2) and Direct Yellow-27 (C28H19N5Na2O6S4) are non-biodegradable organic compound containing azo group and confirmed carcinogenic. Direct Red-81 and Direct Yellow-27 were degraded by photolysis method under 10 watt UV-light irradiation (λ=365 nm) and solar irradiationwith and without C-Ncodoped TiO2 catalyst. The dyes solution was analyzedy UV-Vis spectrophotometer at λ 300-800nm. The optimum mass of C-N-codoped TiO2catalyst was 10 mg. From those methods, concluding solar irradiation method enhanced better degradation than UV-light irradiation, Direct Red-81 and Direct Yellow-27 were degraded 17.37 % and 8.72 % by solar irradiation and the degradation percentage increased to 75.63 % and 71.52 % by the addition of C-Ncodoped TiO2 catalyst for 120 minutes.