Construction Of Activated Carbon Fiber Loaded Manganese Oxide Activated Persulfate System And Its Effect On Sbr Performance

The application of advanced oxidation processes（AOPs）on carbon materials for the removal of new organic pollutants is receiving increasing attention in the field of water treatment.The technique has high reaction rate,broad applicability,and powerful removal capacities.Following the extensive use and research of powdered activated carbon and granular activated carbon,activated carbon fiber（ACF）,which emerged as the third generation of activated carbon materials,has strong single electron transfer capability and great potential for activating persulfate.However,the activated carbon fiber has a rather low catalytic capacity.Related research has demonstrated that adding nano metal oxides can enhance persulfate activation.Due to their strong catalytic qualities（rich valence composition and outstanding catalytic efficiency）,manganese oxides（Mn O_x）are frequently utilized in advanced oxidation processes（AOPs）.Therefore,in this study,a Mn O_x-activated carbon fiber composite catalyst（Mn O_x@ACF）was prepared by loading Mn O_x nanoparticles onto the surface of ACF through an in-situ assembly method to construct an inhomogeneous advanced oxidation system for activated peroxymonosulfate.In addition,a sequencing batch reactor activated sludge process（SBR）was used to simulate the biological treatment system of a wastewater treatment plant.The stability and ecological effects of the Mn O_x@ACF composite catalyst on the biological treatment of antibiotic wastewater system were investigated.The specifics of the study are as follows.（1）The Mn O_x@ACF multivalent composite catalyst was made using a straightforward in situ assembly approach,and the catalytic efficacy of Mn O_x@ACF/PMS for TCH was assessed using a number of catalytic assays and characterisation techniques.The results demonstrated that 0.1 g/L Mn O_x@ACF at p H=5 and 0.1 mmol/L PMS dosage could effectively activate PMS to achieve the TCH with 88.9%removal.The active species generated in the Mn Ox@ACF/PMS system contained both free radicals(SO₄^·─、^·OH)and non-free radicals（¹O₂）,and the unique structure of the Mn O_x@ACF/PMS surface（surface PMS complex）can enhance the PMS activation effect and contribute to the TCH degradation process.In the meantime,the catalytic mechanism and active species of Mn O_x@ACF/PMS were analyzed.（2）By incorporating various concentrations of Mn O_x@ACF into the SBR reactor,the effects of Mn O_x@ACF at various doses（0.05,0.1,0.2,and 0.4 g/L）on the stability of the SBR biodegradation TCH system under long-term operation were studied.The TCH concentration and COD content of the effluent were continuously monitored for30 cycles.All five SBR reactors were able to achieve a stable TCH degradation rate of more than 70.0%,and the effluent COD content was 30.0-40.0 mg/L.（3）The DNA information of all microorganisms in five SBR after 30 cycles of operation was extracted to construct a macrogenomic detabase,and the effects of mixing different concentrations of Mn O_x@ACF on the structure and functional composition of microbial populations in the SBR reactor were investigated using macrogenomic techniques.The results showed that the low concentration of Mn O_x@ACF could stimulate the microbial activity and increase the species community richness in the SBR,and the composition of the dominant bacterial population in the SBR was also changed by the influence of Mn O_x@ACF.Furthermore,the combined effect of Mn O_x@ACF and TCH promoted the increase in the abundance of various functional genes,but the functional structural composition of microorganisms in the SBR reactor was not affected by Mn O_x@ACF.