Naslov
Sorption and fractionation of natural organic matter on kaolinite and goethite

Autori
Maurice, P. ; Namjesnik-Dejanović K. ; Lower, S. ; Pullin, M. ; Chin, P.-Y. ; Aiken, G. R.

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Proceedings of the 9th International symposium on water-rock interaction / Arehart, Greg ; Hulston, John - Rotterdam : Boston (MA) : Taipei : A.A. Balkema Publishers, 1998, 109-113

Skup
9th International symposium on water-rock interaction

Mjesto i datum
Taupo, Novi Zeland, 30.03.1998. - 03.04.1998

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
sorption; fractionation; natural organic matter; chromatography; kaolinite; goethite

Sažetak
High pressure size exclusion chromatography (HPSEC) was used to determine directly the molecular-weight fractionation that occurred upon sorption of the muck fluvic acid (FA) to kaolinite and goethite, at pH 3.7, 22°C, 24 hrs. equilibration. FA sorption affinity was found to be much greater for goethite than for kaolinite, with sorption maxima, Amax=0.22 and 0.05 mgCm-2, respectively. Fractionation measurements agreeed well with theoretical predictions. at concentrations <Amax, for both sorbents, the average molecular weight (Mw) of FA remaining in solution decreased by a s much as several hundred daltons, indicating preferential sorption of the higher molecular weight components. At concentrations >Amax, solution Mw did not change, most probably because preferential sorption was overwheled by excess FA. Polydispersity decreased slighty upon sorption to kaolinite, but there was no significant change for goethite. Our results demonstrate quantitatively the preferential sorption of higher molecular weight components, and show that effects on solution Mw vary as a function of (FA).

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA