| Summary: | The liquid waste from biodiesel production contains primarily glycerol and requires treatment before discharge into waterway. This study reports on the glycerol decomposition using photocatalytic Fenton technique. Visible light-responsive CuFe2O4 photocatalyst was synthesized using a sol-gel method employing Cu:Fe ratio of 1:2 by mol. The photocatalyst was characterized using N2-physisorption, FESEM-EDX, XRD, UV-Vis DRS and particle size distribution. The BET specific surface area of CuFe2O4 was 102.4 m2/g. The morphology of the CuFe2O4 showed irregularly-shaped nanoparticles with good homogeneity in particle size distribution. The results indicate that the solid catalyst exhibited high crystallinity with CuFe2O4 as the main crystallite compound. The band gap energy of the CuFe2O4 was 1.58 eV and the average particle size of the photocatalyst was around 100 μm. In the presence of xenon lamp (250 W), the performance of photocatalytic Fenton degradation of different concentrations of glycerol aqueous solution, different concentrations of hydrogen peroxide and different photocatalyst loadings were studied. The samples in the experiment were analysed using HPLC. The results showed that a minimal amount of photocatalyst loadings (0.1 g/L) was needed to initiate the photocatalytic Fenton reaction. By increasing the concentration of glycerol solution, the degradation of glycerol diminished; however increasing the concentration of H2O2 has increased the glycerol degradation. The degradation at initial glycerol concentration of 27.36 mM shows 60.0% while at 67.41 mM glycerol concentration shows 27.0%. Besides that, adding 819.5 mM H2O2 showed 30% degradation while adding 163.9 mM H2O2 only showed 5% degradation. In addition, statistical evaluation was also carried out to understand the significance of the kinetics results. Full factorial analysis was introduced to screen the factors in the phtocatalytic Fenton degradation of glycerol. The best condition to show higher degradation rate were 27.41 mM glycerol concentration, 819.5 mM H2O2 concentration and 5.0 g/L photocatalyst loadings in the experiment of four hours. Glycerol concentration and concentration of H2O2 affect the glycerol decomposition.
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