To gain an improved understanding of the types of organic compounds that are recalcitrant to water treatment, natural organic matter (NOM) isolates from two drinking water sources (Mt. Zero and Moorabool reservoirs, Victoria, Australia) were separated into fractions of distinct chemical behaviour using resins. Four fractions were obtained from each water source and were organics absorbed to: (1) XAD-8 (very hydrophobic acids, VHA); (2) DAX-4 (slightly hydrophobic acids, SHA); (3) bound to an anion exchange resin (charged organics, CHAR); and (4) not absorbed or bound to resins (neutrals, NEUT). These fractions were then tested to determine the capacity of alum to remove them from water and to correlate this with the character of each isolate. The fractions were characterised by the application of high performance size exclusion chromatography (HPSEC), bacterial regrowth potential (BRP), trihalomethane formation potential (THMFP), pyrolysis gas-chromatography mass spectrometry (Py-GC-MS) and thermochemolysis. The highest removals of dissolved organic carbon (DOC) by alum treatment were in waters spiked with the CHAR fractions while the NEUT fractions were the most recalcitrant. The number average molecular weights (Mn) of DOC of the CHAR fractions before treatment were the highest, whilst those of the NEUT fractions were the lowest. After alum treatment, the Mn of the NEUT fractions were only slightly reduced. Results from Py-GC-MS and thermochemolysis indicate that the NEUT fractions had the highest relative proportion of saccharide derived organic material. Nonetheless, the BRP of waters spiked with the NEUT fractions differed markedly, indicating that organics recalcitrant to alum treatment can vary substantially in their chemical composition and capacity to support microbial growth.
Skip Nav Destination
Article navigation
Research Article|
December 01 2002
Application of a fractionation technique for better understanding of the removal of natural organic matter by alum coagulation Available to Purchase
J. van Leeuwen;
*Australian Water Quality Centre, SAWATER, CRCWQ&T
E-mail: [email protected]
Search for other works by this author on:
C. Chow;
C. Chow
*Australian Water Quality Centre, SAWATER, CRCWQ&T
Search for other works by this author on:
R. Fabris;
R. Fabris
*Australian Water Quality Centre, SAWATER, CRCWQ&T
Search for other works by this author on:
N. Withers;
N. Withers
*Australian Water Quality Centre, SAWATER, CRCWQ&T
Search for other works by this author on:
D. Page;
D. Page
*Australian Water Quality Centre, SAWATER, CRCWQ&T
Search for other works by this author on:
M. Drikas
M. Drikas
*Australian Water Quality Centre, SAWATER, CRCWQ&T
Search for other works by this author on:
Water Supply (2002) 2 (5-6): 427–433.
Citation
J. van Leeuwen, C. Chow, R. Fabris, N. Withers, D. Page, M. Drikas; Application of a fractionation technique for better understanding of the removal of natural organic matter by alum coagulation. Water Supply 1 December 2002; 2 (5-6): 427–433. doi: https://doi.org/10.2166/ws.2002.0200
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
eBook
Pay-Per-View Access
$38.00