Nitrogen-doped carbon nanotube (N-CNT) was used as an activator to activate peroxymonosulfate (PMS) to degrade azo dye,Acid orange 7(AO7) in aqueous solution.The results indicated that N-CNT exhibited a much better performance on activating PMS to decolorize AO7 than activated carbon (GAC),the removal of AO7 could reach 99% after 60min with 400mg/L of N-CNT dosage,40/1of PMS/AO7 molar ratio.The degradation mechanism of AO7 in N-CNT activated PMS system was explored,and SO4-· was found to be dominantly responsible for AO7 degradation,which mainly took place on the surface of N-CNT.The The initial pH had a significant effect on the AO7 degradation,and pH 3.0 was most favorable for its degradation.In addition,the degradation of AO7 was accelerated after addition of Cl-、SO42- and CO32-;From the analysis of UV-vis spectra and TOC analysis indicated that the azo band and naphthaline ring of AO7 that were destructed and then mineralized into CO2 and H2O.
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