Abstract
A gas chromatographic method for the determination of sodium nitrilotriacetate (NTA) and sodium citrate (SC) in granular detergent was investigated.
NTA and SC were directly converted into their n-propyl esters under a continuous flow of dry hydrogen chloride gas, without any previous acidification. The optimum reaction time was found to be 2 hours at the reflux temperature of n-propyl alcohol. These volatile derivatives were separated and determined on a silicone OV-17 column (1m×3mm i.d.), with n-propyl myristate as an internal standard.
NTA and SC were quantitatively rceovered from a standard detergent in the range of usual formulations. This method allows a rapid simultaneous determination of NTA and SC in granular detergents.
