Mixtures of polycarboxylic acids and their salts with sodium
tripolyphosphate and sodium pyrophosphate have been investigated in the
presence of ammonium oxalate and sodium carbonate. Some of these mixtures
demonstrated good chelating power synerg
y and some mixures inhibited the
chelating power of the individual components from which the mixures
composed of. The chelating power synergy of some mixtures can be used for
enhancing the function of the builders and consequently decrease the weight of
the detergent meanwhile the inhibition of the chelating power in the other
mixtures can be used for precipitating their components in the treated water in
optimum conditions. It is worth to mention that the chelating powers of sodium
tripolyphsphate and citric acid increased as many as 3-88 times by changing
some experimental conditions.