| It is very important and challenging to develop efficient and green oxygen technologyinenvironmentalcatalysisfiled.Amongoxygen technologies,advanced oxygen processes（AOPs）were utilized widely due to rapid oxidation and removal of organic contamination by strong oxidizing free radicals produced in AOPs systems.Recently,some researchers reported that persistent free radicals（PFRs）,which were once thought hazardous substances,could enhance the removal of organic contamination significantly.PFRs widely exist in carbon materials,tiny particles in the air,tar balls,incineration fly ash and particles produced from wood and coal burning.In this study,CuO was supported on carbon fibers（CFs）containing PFRs,obtaining a novel catalytic fiber（CuO-CFs）.Using permonosulfate（PMS）,persulfate（PS）as oxidants,dyes as probe compound,we investigated the catalytic activity of CuO-CFs.Thesis focused on the performance,re-use of CuO-CFs and the mechanism of PMS and PS activation.The main research contents are as follows:CuO was supported on carbon fibers（CFs）containing PFRs,obtaining a novel catalytic fiber（CuO-CFs）.The structure of catalytic fiber was characterized by X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,scanningelectronmicroscope（SEM）,transmissionelectron microscope（TEM）and Fourier transformed infrared（FTIR）.The atomic absorption spectrum（AAS）indicated that the CuO loading was about 2.5wt%.With PMS as oxidant and acid red 1（AR1）as probe compound,we investigated the catalytic activity and stability of CuO-CFs.The results showed that CuO-CFs/PMS system could remove 99.5%AR1 in 10 min,which was much more efficiently than CuO/PMS system（19%）.That CFs transfer electron to CuO speeded up transformation from Cu（II）to Cu（I）and then enhanced CuO-CFs/PMS system to generate more reactive oxygen.After 5cycles,CuO-CFs/PMS system could still remove more than 90%AR1,suggesting that catalytic fiber CuO-CFs possesses excellent sustained catalytic ability.Moreover,CuO-CFs/PMS system could also efficiently remove other dyes（such as reactive red X-3B,reactive brilliant red 3BF,cationic dye MB,fluorescent dye Rh6B）.Combined electron paramagnetic resonance（ERP）,we adopted some radical scavengers such as methanol（MA）,tert-butyl alcohol（TBA）,benzoquinone（BA）and sodium azide（NaN3）to verify 1O2,·OH,SO4·-and O2·-were generated from CuO-CFs/PMS and among these reactive xogen,1O2 played an important role in catalytic process.In order to investigate catalytic ability of CuO-CFs to persulfate,PS was chosen as oxidant to investigate catalytic oxidative activity of CuO-CFs/PS with AR1as probe compound.Otherwise,we compare the difference between CuO-CFs/PS system and CuO-CFs/PMS system.The results showed that CuO-CFs/PS system could remove 98.4%AR1 in 10 min,same as CuO-CFs/PS（99.5%）,but rate contant（kobs）of AR1 removal in CuO-CFs/PS system（0.4759 min-1）is lower than CuO-CFs/PS system（1.0095 min-1）,and oxidant consumption index（X）in CuO-CFs/PS system（3.9）is higher than CuO-CFs/PMS（2.53）,suggesting that CuO-CFs/PMS system oxidant consumption rate is higher.Combined electron paramagnetic resonance（ERP）,we adopted some radical scavengers such as methanol（MA）,benzoquinone（BA）and furfuryl alcohol（FFA）to verify 1O2,O2·-and·OH were generated from CuO-CFs/PS and among these reactive oxygen,1O2and O2·-played an important role in catalytic process.Otherwise,compared to CuO-CFs/PMS system,activation energy of CuO-CFs/PS system（34.45Kj/mol）is 1.58 times higher than CuO-CFs/PMS system（21.93 KJ/mol）. |
