Synthesis of iron modified sugarcane bagasse activated carbon for oxidation degradation of malachite green

Abstract

Iron (II, III) oxide (Fe3O4), activated carbon (AC) and Fe3O4/AC composites at various weight ratios (1:1, 3:1 and 1:3) were synthesised successfully using chemical impregnation method. The synthesised composite samples were then analysed by using scanning electron microscope coupled with energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD) and fourier transform infrared spectroscopy (FTIR). Heterogeneous photo Fenton and Fenton-like processes were applied in degrading malachite green. Fe3O4/AC composite samples showed higher catalytic activity as compared to pure Fe3O4 and AC. The composite of Fe3O4/AC at weight ratio of 1:1 (FeAC11) was determined to be the optimal mixing weight ratio as it possessed the highest heterogeneous photo Fenton and Fenton-like degradation efficiency of malachite green. The highest degradation efficiency of malachite green was achieved at initial dye concentration of 30 ppm, FeAC11 dosage of 0.8 g/L, solution pH of 5, 4 mM of H2O2 with the degradation efficiency of 89.22 % after 3 min. The composite sample FeAC11 depicted high stability as only little amount of leached iron (about 4 mg/L) was detected by inductively coupled plasma optical emission spectrometry (ICP-OES). Pseudo second-order kinetic was best fitted to the reaction kinetic of heterogeneous photo Fenton and Fenton-like on the degradation of malachite green at different solution pH.