Separation of Benzene, Toluene, Ethylbenzene and P-Xylene from Aqueous Solutions by Carbon Nanotubes/Polyvinylidene Fluoride Nanocomposite Membrane

Abstract

Carbon nanotubes/polyvinylidene fluoride (PVDF) nanocomposite membranes (abbreviated as CPMs) were fabricated to study their physicochemical property and separation efficiency of organic pollutants such as benzene, toluene, ethylbenzene and methylbenzene (abbreviated as BTEX) from aqueous solutions. The rejection coeffi-cients (R) of BTEX depend on the CNT content of CPM, pore size of membrane, molecule size of BTEX, permeation pressure (P), feed concentration (Cf) and temperature. The CNT contents were 5%, 10% and 15% in CPM have been conducted. The 10% CNT content of CPM (10-CPM) has not only higher water flux but also the relatively higher R as comparing of 5% and 15% CNT of CPM. The R decreased with increasing P, Cf and temperature but has no significant influence on ionic strength (μ). The R of BTEX were found in the order as B ≈ X which revealed the major mechanism of BTEX separation with CPM was related to molecule size of BTEX (B ≈ X). It exhibits that the size exclusion plays the important role in BTEX separation. According to the result of separation of BTEX by 10-CPM, the R of BTEX not only have above 80% with relative lower pressure but also have higher water flux as compared of other nano-filtration. This suggests that the 10-CPMs possess good potential for BTEX removal in wastewater treatment.