Journal of membrane science vol:279 issue:1-2 pages:311-319
This paper investigates the relative contribution of convection, diffusion and charge effects during transport of dissolved organic compounds in aqueous solution using nanotiltration membranes. Measurements were carried out in a crossflow nanotiltration unit and in diffusion cells using four organic compounds (tryptophane, raffinose, benzylidene acetone and mandelic acid) in aqueous solution and five commercial nanofiltration membranes (UTC-20, Desal-HL-51, NTR-7450, NF270 and NF-PES-010). Diffusion was analyzed by the Donnan model for diffusion across a charged membrane. The charge effect was studied by changing the pH of the feed Solution, which influences both the membrane and compound charge.