Study On Oxidative Degradation Of Direct Pink 12B With Photo/Ultrasonic/Microwave- Enhanced Fenton Process

Direct dyes have been produced commercially for over 100 years.As an important and widely used type of dyes,its wastewater are also complicated, which involves various organic dyes and their intermediates. What's more, the wastewater usually has those characters: deep color, high concentrations, long resistance to biodegradation, strong toxicity, wide fluctuation of pH, great variation of ingredients, large waste streams and so on. Therefore, dye wastewater treatment has increasingly become one of the heated topics in the field of environmental engineering.Fenton hydrocarbonylation, being a senior oxidation technique, brings about hydroxyl free radical(?OH) which is efficacious to degrade organic compounds, even to completely transforming organic compounds into harmless inorganic substances. In this paper, sunlight,ultrosonic and microwave are introduced into Fenton reaction system, aiming to improving degradation of polycyclic aromatic hydrocarbon dyes—Dirct pink 12B. The following contents are included: deriving the optimum experimental condition from orthogonal experimental design based on single-factor experiment; investigations on photo-Fenton,ultrosonic-Fenton,microwave-Fenton synergistic effects; via controlling experiment, kinetic equation for photo-Fenton, ultrosonic-Fenton, microwave-Fenton oxidizing reaction to degrade target organics is obtained.By experiments, it is suggested that the couple of sunlight-Fenton prossess of synergistic effects which enable enhance color and COD removal rate of Direct pink 12B.For the direct pink 12B solution with the volume of 100mL and the concentration of 500mg/L, the optimum experimental condition is resulted: pH=3.5, 50uL 30%H₂O₂, 220uL 18mmol L-1Fe²⁺and 30min sunlight interactions. Then, 100% of Direct pink is removed and 77.8% for COD. On original condition that pH=3.5, kinetic equation for Fenton reaction in case of sunlight radiation to degrade Direct pink 12B is as: V=-((dP)/(dt))=1.4×10^-2×P^0.39×F^1.7×E^0.33Combination of ultrosonic and Fenton agents prossess of synergistic effects which enable enhance color and COD removal rate of Direct pink 12B.For the direct pink 12B solution with the volume of 100mL and the concentration of 500mg/L, the optimum experimental condition is resulted: pH=3.0, 40uL 30%H₂O₂, 160uL 18mmol L-1Fe²⁺, ultrosonic power 100W and 30min ultrosonic interactions. Then, 100% of Direct pink is removed and 79.5% for COD. On original condition that pH=3.0, kinetic equation for Fenton reaction in case of ultrosonic radiation to degrade Direct pink 12B is as: V=-((dP)/(dt))=7.5×10^-7×P^0.78×F^2.05×E^0.91×H^0.93Couple of microwave-Fenton prossess of synergistic effects which enable enhance color and COD removal rate of Direct pink 12B.For the direct pink 12B solution with the volume of 100mL and the concentration of 500mg/L, the optimum experimental condition is resulted: pH=3.5, 15uL 30%H₂O₂, 15uL 18mmol L-1 Fe²⁺, Microwave power 320W and 10min Microwave irradiation interactions. Then, 100% of Direct pink is removed and 79.5% for COD. On original condition that pH=3.0, kinetic equation for Fenton reaction in case of ultrosonic radiation to degrade Direct pink 12B is as: V=-((dP)/(dt))=5.4×10^-11×P^3.26×F^1.66×E^1.28×H^1.71...