A study on performance of PVC/MWCNTs nanocomposite membranes in humic acid solution filtration

In this research, the effect of multiwall carbon nanotubes (MWCNTs) on the performance of polyvinyl chloride (PVC) membrane in the filtration of humic acid solution was investigated. The FESEM results showed that the number of surface pores in nanocomposite membranes is more than that of PVC membrane. The tensile strength and abrasion resistance of membranes increased with increasing MWCNTs up to 0.3 wt.%. It was also observed that water flux of membrane containing 0.3 wt.% MWCNTs increases up to 484.7 L/m2h. The decrease of water contact angle from 88.6° for PVC membrane to 70.2° for 0.3 wt.% MWCNTs membrane showed that the hydrophilicity of membranes increases with increasing MWCNTs. It was also found that the rejection of humic acid solution with MWCNTs membranes is more than that of PVC membrane. The analysis of fouling mechanism of membranes revealed that the cake formation model is dominant mechanism for all membranes and cake filtration-complete blockage model fits the volume-time data.