Non-homogeneous Light Fenton Reaction Catalyst And Its Application

The homogeneous UV/Fenton system's pH had to be adjusted to a limited range (2-5) in the oxidation processes of the azo dye and the ferric ion give away and cause the the second pollution.The dye decoloration was effectively carried out in heterogeneous Photo-Fenton system and avoids these problems.In this paper, two series of catalysts FS and FCS were preparated by mixing of sodium alginate and ferric chloride or copper sulphate, the weight and the diameter of the bead were measured and then the contents of ferric ions and copper ions on the catalysts were analyzed, and catalysts were investigated by XRD and FT-IR. Then the photocatalytic decoloration of Active Red MS, Active Bleu B and Acid Black 234 in the presence of H₂O₂ was conducted. A few factors affecting the photocatalytic decoloration of these dyes such as dosage of the catalysts, pH value, irradiation intensity and concentration of the dyes on the photocatalytic decoloration and the kinetic model of dyes were investigated. The photocatalytic degradation of three azo dyes was examined by UV - VIS spectrum. Catalyst FCS had more photocatalytic activity than catalyst FS, high irradiation intensity resulted in the enhanced decoloration level. The photocatalytic decolorations of three dyes were improved by increasing the dosage of catalysts, appropriate H₂O₂ and decreasing the dye concentration. The decoloration of dyes was limited significantly in the prensence of inorganic salts. The photo-induced decoloration of two reactive dyes could be carried out both in acidic and basic medium in the presence of catalysts and H₂O₂ under irradiation. The decoloration reaction followed a pseudo first order kinetic model, and the constant reduced as the irradiation intensity weakening, dye concentration increasing and there were inorganic salts in the solution. The reaction of two reactive dyes was described by Langmuir-Himshelwood reactive model. The most of conjugate structure and aromatic part of azo dye were destroyed after being photocatalytic degradation, Catalyst FCS enhanced the degradation more significantly than catalyst FS.