Charge Neutralization Study of Mixtures of Al13 with Alum
Chemistry and Biochemistry
Partially neutralized aluminum solns. with a basicity ([OH-]/[Al3+]) of 2.5 contain the polymeric aluminum moiety, [AlO4Al12(OH)24(H2O)127+], represented as Al13 at more than 90% of the total Al. Coagulants can be titrated into raw water until a zero zeta potential is achieved. Water types (pH range of 7.1 to 7.9) of varying alky. (50 and 100 ppm CaCO3) and varying turbidity (∼9.0, ∼62, ∼160 NTU) achieved a zero zeta potential with mixts. of Al13 and aluminum sulfate using the least amt. of total aluminum compared to aluminum sulfate (monomeric aluminum) alone.
Koether M, Fraser D, Owens A, Murphy R. 2010. Charge neutralization study of mixtures of Al13 with alum. Journal of Undergraduate Chemistry Research 9(2):52-4.