4, 5-dihydroxy-l, 3-benzenedisulfonic acid Tiron

A post-column derivatization with subsequent photometric detection has also been developed for the determination of aluminium. Using a mixture of ammonium sulfate and sulfuric acid, aluminium is separated as A1S04+ ion on a cation exchanger. It forms a stable complex with the disodium salt of 4,5-dihydroxy-l,3-benzenedisulfonic acid (Tiron) at pH 6.2 which can be detected at 313 nm. 

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