Study On Degradation Of Organic Pollutants By Fe-NC As Fenton Catalysts

There are some disadvantages in traditional Fenton process,such as large consumption of acid and alkali,massive formation of iron mud which was hazardous waste.To improve these problem,three iron-doped nitrogen carbon material（Fe-NC）catalytic materials were prepared by the chelation of nitrogen atoms（N）and ferrous ions(Fe²⁺).Fenton system was constructed to determine the catalytic efficiency of the three materials,using rhodamine B and tetracycline as target pollutants.Combining characterization and experimental data to deeply explore the reaction process,the research results were as follows:1)Fe-NC catalyst was prepared by using porous CaCO₃ as template,FeCl₃ as iron source,CCl₄ and C₃H₁₀N₂ as carbon source and nitrogen source.Using SEM,TEM,XPS and other methods to characterize its physical structure and chemical properties.Fe-NC catalyzed H₂O2 to degrade rhodamine B.The result showed that ·OH was the main active substance.Within 60 min,more than 90% of rhodamine B could be degraded.This reaction accorded with the first-order reaction kinetic.2)CN@Fe PPc catalyst was prepared by thermal polymerization using iron phthalocyanine and melamine.TEM,XRD,XPS and other methods were used to characterize its physical structure and chemical properties.CN@Fe PPc were constructed to catalyze H₂O2 for degradation of rhodamine B under visible light.The result showed that ·OH and photogenerated h+ were the main active substances.99.89% of rhodamine B could be degraded within 90 min.3)Fe-NC（M is the abbreviation of methanol）was obtained by using methanol as the solvent,FeCl₃ and melamine as the iron source,nitrogen source and carbon source,respectively.SEM,TEM,XPS and other methods were used to characterize its physical structure and chemical properties.Fe-NC（M）catalyzed H₂O2 to degrade tetracycline.The result showed that ·OH and high-valent iron（≡Fe^V=O）were the main active substances.This system could degrade more than 80% of tetracycline within 90 min.The fitting reaction kinetics showed that this reaction accorded with the second-order reaction kinetic.4)Fenton system using Fe-NC as catalyst has a wide pH range.Fe-N bond can reduce the loss of iron,so as to achieve efficient and stable catalysis.