Prussian Blue Doped Modified Biochar Activates PDS To Degrade CTH/BPA

With the enhancement of detection technology,emerging pollutants such as endocrine disruptors,drugs and personal care products,which are difficult to degrade and highly toxic,are gradually found in water bodies.They cannot be removed by traditional biological treatment methods.Among them,the advanced oxidation technology using persulfate as the oxidant has become a research hotspot due to its advantages of low cost,high redox potential,and wide p H range.Modified biochar has become a commonly used catalyst due to its low cost,large specific surface area and high activity.In this paper,biomass products prepared from two common plants in Northwest China and mature for commercial application are selected: Artemisia gum and psyllium husk powder as biomass templates,and Prussian blue as heteroatom dopant.Catalytically active iron and nitrogen atoms co-doped magnetic biochar material can activate persulfate to efficiently degrade chlortetracycline hydrochloride and bisphenol A.The specific research contents are as follows:（1）Using artemisia gum as a biomass template,grinding with Prussian blue at a certain mass ratio and then calcining under nitrogen protection to obtain magnetic biochar materials.The research results show that the prepared catalyst has a good degradation effect on chlortetracycline hydrochloride.Among them,the biochar obtained by calcination at 500 ℃ and the mass ratio of Prussian blue and artemisia gum is 2:1 has the best catalytic effect: 0.4 g/ L persulfate and 0.6 g/L catalyst can degrade more than 88% of chlortetracycline hydrochloride（initial concentration 20mg/L）in 1 h.In the presence of external anions and organic matter,the degradation efficiency is inhibited.When the initial p H of the solution reaches 11,the degradation efficiency is greatly reduced,and half of the catalytic effect can be retained after repeated use for four times.A series of characterizations were performed on the biochar to analyze the physicochemical properties of the catalyst surface,and the analysis of the active species during the degradation process found that the main active species were superoxide radicals and singlet oxygen.（2）An iron-nitrogen co-doped magnetic biochar material was prepared by a simple one-step pyrolysis method using Prussian blue and psyllium husk powder,and it was used as an activator of persulfate to degrade bisphenol A.The catalyst with the best catalytic effect was obtained at 900 ℃ and the mass ratio of 1:1,and the difference in the degradation effect of bisphenol A under different conditions such as temperature,initial p H,amount of persulfate,and amount of catalyst was studied.The properties of the materials were characterized by SEM,TEM,XRD,FTIR,Raman spectroscopy,VSM,Zeta potential and other methods.Free radical quenching experiments and ESR spectra showed that the main active substances in the catalytic degradation process were superoxide radicals,singlet oxygen,and non-radical pathways of surface-bound active substances.The electrochemical test results showed that pollutants and Electron transfer between catalysts.Under the conditions of 25℃,0.2 g/L persulfate and 0.2 g/L catalyst,more than 99% of bisphenol A can be degraded in 20 minutes.a potential catalyst.