| Energy and environment have become a foucs problem in the world.How to develop clean and environment-friendly new energy catalyst and to achieve high-efficient removal of environmental pollutants is an important driving force and development direction of innovation of energy and environmental technology in the new era.Hydrogen peroxide?H2O2?plays an important role in the advanced oxidation technology based on hydroxyl radical group?·OH?.Compared with other water treatment technologies,in-situ electrocatalysis technology not only reduces the cost of chemicals storage,transportation and distribution,but also greatly improves the utilization efficiency of chemicals in catalytic reaction.Thus it avoids material waste and slows down secondary pollution,and greatly improves the water treatment efficiency.Persulfate method is also one of the advanced oxidation methods.Its oxidation mechanism is similar to that of Fenton method,which both degrades organic compounds by producing oxidative radical groups.It possesses high selectivity,wide pH application range and strong oxidation ability.Since the oxidation ability of persuflate is stronger than hydroxyl radical group,the application of advanced oxidation technology based on Sulfate radical?SO4-·?in wastewater purification has attracted more attention of environmental scientists.Three-dimensional electro-Fenton technology gained remarkable achievment in the degradation of organic pollutants due to its strong catalytic-oxidation ability and easy control characteristics.In this paper,in-situ electrocatalysis method producing hydrogen peroxide combined with Fenton oxidation technology is proposed to achieve the efficient removal of refractory organic compounds-Bisphenol A?BPA?.In three-dimensional electro-fenton,spherical AuPd alloy and layered iron oxylchrodile?FeOCl?composites were used as the third electrode to in-situ produce hydrogen peroxide and to realize efficient heterogeneous Fenton reaction.On the other hand,advanced oxidation technology base on SO4-·is also an important type of advanced oxidation technologies.Carbon nanotubes/cobalt ferrite?CNTs/CoFe2O4?composites with good adsorption and magnetic recovery were synthesized by one-step method.Further discuss was conducted in the effect of adsorption capacity and valence composition of transition metals on the activation of Peroxymonosulfate?PMS?by cobalt ferrite.Research contents are divided into two parts as follows:?1?A new particle electrode based on spherical AuPd-FeOCl composite was synthesized by impregnation-reduction method.XRD,FESEM and XPS were used to characterize the morphology,structural characteristics and element composition of AuPd/FeOCl composites.AuPd/FeOCl as the third electrode,was used to successfully achieved the efficient removal of the target pollutant-BPA.The results showed that5%wtAuPd/FeOCl had the best catalytic degradation effect on BPA in the three-dimensional electro-Fenton catalytic process.40 mg/L BPA was completely removed in56 minutes,major mineralization was achieved in 136 minutes and the optimum pH value was 4.The electrochemical result showed that 5%AuPd/FeOCl had lower oxygen-reduction overpotential and the yield of H2O2 was 0.19 mmol L-1g-1.with the increase of current density,the electrocatalytic degradation efficiency increased.The catalytic efficiency in five cycles did not decrease significantly.The total amount of iron ion leakage is less than 0.79 mg/L.?2?CNTs/CoFe2O4 composites were prepared by one-step hydrothermal method.The surface morphology,structural characteristics,element composition and specific surface area of CNTs/CoFe2O4 composites were analyzed by XRD,FESEM,TEM,XPS and BET.The results showed that CFO-17 activated PMS with the largest specific surface area had the best degradation effect of P-nitrophenol?4-NP?.The removal rate of 10 mg/L 4-NP reached 90%within 24 min.The catalytic-activation efficiency of PMS increases with the increase of temperature and dosage. |
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