Spectrophotometric and inductively coupled plasma atomic emission spectrometric determination of titanium in ilmenites after rapid dissolution with phosphoric acid

The use of 85% phosphoric acid in borosilicate conical flasks for the dissolution of ilmenites at 230 +/- 10 degrees C is reported. The samples were quantitatively dissolved in less than 13 min. Titanium was determined by both spectrophotometry and inductively coupled plasma atomic emission spectrometry ICP-AES. Vanadium and iron were determined by ICP-AES. In several samples of ilmenites analyzed, the TiO(2) concentration was in the range 10.6-57.5% and those of FeO and V(2)O(5) were in the ranges 31.6-51.4% and 0.39-1.32%, respectively. In the spectrophotometric method, vanadium interference occurs only when the Ti V concentration ratio is