Optimisation of Microwave Dissolution of Refractory Minerals by Factorial Design

摘要

The applicability of commercial laboratory microwave aided digestion system was evaluated for the use in the digestion of a wide range of geological materials and optimisation of the digestion programme for determination of titanium and chromium. The optimisation of dissolution programme and the involved parameters are carried out using factorial design of experiments. Microwave digestion depends on microwave power, the dissolution time and the volume of acids used. A regression equation involving the above three parameters was developed. The parameters are varied at two levels for design of experiments and three base level experiments were also carried out to estimate error and standard deviation. The optimised digestion procedure provided a recovery of 98-100% for titanium in IGS-31 and for chromium in CHR-Bkg.