
TY  - JOUR
A1  - Kipton, H 
A1  - Powell, J 
A1  - Rate, AW 
T1  - Aluminum-Tannin Equilibria: A Potentiometric Study
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1987
VL  - 40
IS  - 12
SP  - 2015
EP  - 2022
KW  - 
UR  - https://doi.org/10.1071/CH9872015 
N2  - The equilibrium reactions between aluminium(III) and an epicatechin polymer or tannin (T) have been studied by potentiometric titration at 25ºC, I = 0.001 M. The tannin, which has on average ten 1,2-dihydroxybenzene units per molecule, encapsulates the aluminium ion to form a bis(l,2-diphenolato) complex at pH 5-7. Stability constants are reported for Al(TH-2) (logK11-2, -3.95 ± 0.05), Al(TH-3) (logK11-3, -4.5 ± 0.1) and Al(TH-4) (logKl1-4, -5.7 ± 0.2). A small chelate effect arising from coordination of remote pairs of 1,2-diphenolato groups was observed. 
ER  -

