INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH, cilt.9, sa.3, ss.991-1000, 2015 (SCI-Expanded)
Magnetite (FeO center dot Fe2O3) nanoparticles immobilized on silica and modified by treatment apolaccase were used to decolorize the industrial wastewater from basic red 9 (BR9 by way of Fenton and Fenton-like processes. The surface changes to the silica were determined by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and energy-dispersive X-ray spectroscopy. The decolorization system's optimum parameters, 3 <= pH <= 9; 20 degrees C <= Temp. <= 80 degrees C; initial BR9 concentration (0-50 ppm), and adsorbent concentrations (0-0.2 g/50 mL) were studied to understand their effects on BR9 removal. The optimal parameters values were: pH: 6.0, temperature, 40-60 degrees C; contact time, 30 min; initial BR9 concentration, 50 ppm; and adsorbent concentration: 0.1 g. Under these conditions immobilized magnetite nanoparticles and their apolaccase modified counterparts showed decolorization efficiencies of 81.01% and 88.6%, respectively, for the removal of BR9 from industrial waste water by way of Fenton and Fenton-like processes. These experiments also showed the adsorbent to be re-useable, cheap, biocompatible, easy to prepare, nontoxic (nanomagnetite particles, H2O2 and silica fume) and capable of generating Fenton reaction conditions with or without additional treatment with apolaccase. The adsorbent was shown to be useful in the decolorization of toxic dyes from industrial wastewater.