Non-woven cotton fabric based intimately coupling of photocatalysis and biodegradation system for efficient removal of Cu(Ⅱ)complex in water

摘要

The efficient remediation of heavy metal complexes in water has become a difficult and challenging task owing to their high stability and strong mobility.In this study,a novel strategy was employed for highly efficient removal of Cu-citrate by using intimately coupled photocatalysis and biodegradation(ICPB)system with non-woven cotton fabric as a carrier.Experimental results showed that the ICPB system caused94%Cu removal,which was higher than those of single photocatalysis.After 5 cycles,Cu removal efficiency could still reach 78%within 5 h.The existence of 0–40 mg/L citrate had negligible influence,whereas the presence of 60–100 mg/L citrate exhibited a limited adverse effect on Cu removal(~70%).The decomplexation of Cu-citrate was realized via the function of free radicals and microorganisms.Two main processes,such as bio-adsorption of Cu^(2+) by microorganisms,deposition of Cu^(0) on the surface of material,played important role in Cu removal from aqueous solution.The dominant microorganisms in the system were Proteobacteria,Actinobacteria,Bacteroidetes,Chloroflexi,Chlorophyta,Planctomycetes,and Verrucomicrobia.Furthermore,the performance of ICPB system was also validated through treatment of other heavy metal complexes.This study provided a feasible strategy for the decontamination of heavy metal complexes in wastewater.