Preparation Of Nano-Fe₂O₃ And Study On Degradation Of Methyl Orange And Dibutyl Phthalate

Evironmental pollution has become a global problem affecting human survival and sustainable development, including industrial waste water is the most serious. Among the industrial wastewater problem, dye pollution and plasticizer contamination problems are more prominent. Photocatalysis technology based on TiO2 has provided an effective and promising means for remediation of environmental pollutants in air and water. However, its application for industrial water treatment still remains on the laboratory stage. Studies have shown that Fe2O3 nanoparticles have high photocatalytic activity in catalytic degradation of organic matter under visible light. In this thesis, the preparation of nano Fe2O3, photocatalytic degradation of methyl orange (MO) and photocatalytic degradation of dibutyl phthalate (DBP) will be discussed.Urea and sodium dodecyl sulfate were added to the precursor in the preparation of nano Fe2O3, which will direct to different morphologies of nano Fe2O3. Experimental results show that the addition of SDS prepared Fe2O3 nanoparticles have a smaller particle size. From the data of the FI-IR, XRD, TGA and DSC, we can get this result that under the same preparation conditions, the nano Fe2O3 prepared with SDS is easier washed, more pure and less impurities. While nano Fe2O3 prepared with urea exist a lot of impurities, such as FeOOH,. When selecting the semiconductor catalyst for the photocatalytic degradation experiments, the nano Fe2O3 prepared with SDS has a greater advantage.Photocatalytic degradation of 100 mL MO (simulated dye wastewater) was start with nano Fe2O3/H2O2. Experimental results shows that those influencing factors including pH, the volume of H2O2, the mass of nano Fe2O3, oxygen and the initial concentration of MO affected the efficiency of experiment. When the pH was 2, the mass of nano Fe2O3 was 30 mg, the volume of H2O2 was 30 μL, the degradation experiment is most efficient, and the degradation rate is more than 96%. While the volume of H2O2 was 100 μL, the rate can reach a higher level with 99%, the volume of 30 uL was also selected taking into account the use of resources.Photocatalytic degradation of 100 mL DBP (simulated plastic agents wastewater) was start with nano Fe2O3/H2O2. Experimental results shows that those influencing factors including pH, the volume of H2O2, the mass of Fe2O3 and the initial concentration of DBP affected the efficiency of degradation experiment. The data of experiment shows that when pH was 6.5, the mass of nano Fe2O3 was 30 mg, the volume of H2O2 was 0.5 mL, the degradation experiment is most efficient. The degradation rate is 99%. Via GC/MS, we can explore the degradation process and mechanism. The data of GC/MS shows that degradation process may produce to benzene, formaldehyde, o-phthalic anhydride, etc at 10 min; toluene, 2-butyl octanol, etc at 30 min; 2-ethyl-butene, CO2 and H2O, etc at 60 min.