Acetyl-D-glucopyranoside functionalized carbon nanotubes for the development of high performance ultrafiltration membranes

Acetyl-D-glucopyranoside functionalized MWCNTs (gCNTs) were prepared and used in the fabrication of nanocomposite UF membranes by phase inversion process using different amounts of polysulphone, polyvinylpyrrolidone and gCNTs. The fabricated membranes were then treated with NaOMe solution in anhydrous methanol for deacetylation of 2,3,4,6-tetra-O-acetyl-oilucopyranoside group to obtain o-glucopyranoside functional group on gCNTs. The UF membranes were characterized by different techniques to understand membrane morphology, water contact angles, thermal behaviour and other physical characteristics. The transport properties of the membranes were determined by permeating pure water, aqueous solutions of different molecular weight polyethyleneoxides and polyethyleneglycol, bovine serum albumin (BSA) solution and oil-water emulsion at 2 bar operating pressure. The deacetylated nanocomposite membrane (PSF-PVPgCNT = 92.1-7.7-0.2 wt ratio, CM1) showed higher BSA solution flux (121 LMH) compared to the other membranes (composite membranes: 42-109 LMH; PSF-PVP = 57-87 LMH). The deacetylated nanocomposite membrane (CM1) exhibited maximum flux of 112 LMH with oil rejection of 100% for oil-water emulsion feeds. The deacetylated nanocomposite membranes showed higher flux recovery ratio (FRR = 74-90%) compared to the untreated composite membranes (FRR = 55-77%) and PSF-PVP blend membranes (FRR = 50-62%) for oil water emulsion feeds. The D-glucopyranoside CNTs have great potential for the fabrication of high performance composite membranes with enhanced antifouling property.