Rapid compleximetric determination of Aluminium and Titanium in common ores and silicates

Abstract

A rapid compleximetric method is presented for the determination of aluminium and titanium in ores and silicates such as bauxite, clay, ilmenite, cements and ceramic products. Excess of EDTA is added to an aliquot of the acid sample solution, the pH is adjusted with hexamine and the excess of EDTA is titrated with a combined solution of copper and zinc in the presence of xylenol orange and PAN as indicators. For the simultaneous titration, fluoride is added to release the EDTA combined with both aluminium and titanium. For the stepwise titration, phosphate is added to release the EDTA combined with titanium, and then fluoride is added to release the EDTA combined with aluminium. The method avoids the problem of titanium hydrolysis encountered by previous workers.