The application of microwave digestion in decomposing some refractory ore samples with solid fusion agent

Area of Science:

• Analytical Chemistry
• Materials Science
• Geochemistry

Background:

• Refractory ores are vital economic resources, but their complex composition challenges traditional sample pre-treatment.
• Accurate elemental analysis relies on effective decomposition of refractory ore samples.

Purpose of the Study:

• To develop a rapid, efficient, and simple microwave digestion technique for refractory ore sample pre-treatment.
• To investigate the role of a solid fusion agent and water in microwave-assisted decomposition.
• To compare the developed technique with traditional fusion methods.

Main Methods:

• Microwave irradiation of refractory ore with a sodium peroxide/sodium carbonate solid fusion agent in a corundum crucible.
• Utilizing a drop of water to initiate an exothermic reaction for enhanced decomposition.
• Digestion time of 15 minutes for 0.1 g ore sample with 3.0 g fusion agent.

Main Results:

• Complete decomposition of refractory ore samples achieved in minutes.
• Excellent reproducibility and precision for elements like Mo, Fe, Ti, Cr, and W (RSD < 6%).
• Analytical results closely matched traditional fusion methods, with minor deviations for Cr.

Conclusions:

• The developed microwave digestion technique is simple, economical, fast, and energy-saving.
• Water plays a crucial role in initiating the exothermic reaction for efficient decomposition.
• This method offers a viable alternative to conventional fusion techniques for refractory ore analysis.