The
performance of a disc tube (DT) methodology, originally designed for reverse
osmosis (RO) in desalination, and applied here for ultrafiltration (UF) and
nanofiltration (NF) of dissolved organic matter (DOM) in a set of fresh (0ppt), brackish (10ppt) and saline (30ppt) waters at low (1 - 2mg/L),
medium (5 - 6mg/L) and
high (10-12mg/L) dissolved organic carbon (DOC) content
is presented. The DT module allows for time efficient processing of large volumes
of sample and can be operated with RO, NF and UF membranes. We examined the
performance of a NF membrane with nominal molecular weight cut-off (MWCO) of
500 Da and UF membranes with MWCO of 1 kDa and 10 kDa. Throughout the
experiments we monitored DOM in terms of DOC, UV-absorption coefficient ratios
(E2/E3) and the specific UV-absorbance at 254 nm (SUVA254).Detailed protocols for operating the disc tube
modules are proposed. The membranes can be efficiently cleaned to provide low
carbon blanks (<0.2mg/L). Calibration
confirmed separation of high and low molecular weight standards into the
retentate and permeate fractions, respectively. DOC mass balance of
fractionated DOM samples showed good recoveries (123% ±32%
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