Coupling of acrylic dyeing wastewater treatment by heterogeneous Fenton oxidation in a continuous stirred tank reactor with biological degradation in a sequential batch reactor.
In this study, heterogeneous Fenton-like degradation of reactive azo dye Rhodamine 6G in water was investigated over a CuFeZSM-5 zeolite catalyst prepared by hydrothermal synthesis. At initial pH of 3.4, a color removal of 100% was achieved after a reaction time of 45 min. TOC elimination was measured to be 51.8% after 2 h of oxidation. Initial decolorization rate was described by an equation of -r(A0) = 4.56 x 10(2) e(-24.83/RT)C(R6G,0)C(0.35)(H2O2,0) where R is in kJ/mol. The leaching of iron and copper cations from zeolite structure into the solution during oxidation was dependent on pH strongly. The regulation of pH from 6.5 (dye solution pH) to 3.4, increased leaching for iron from 0.7 to 0.8 mg/dm3 and for copper from 1.4 to 2.1 mg/dm3. The copper was totally leached from the catalyst during the process at pH 3.4.