1) The main phases of tungsten slag are iron/manganese oxides, silicates and silica, etc., and contain some amorphous substances. Tantalum and niobium are mainly wrapped in the phase containing silicon and manganese.

2) The silicate in tungsten slag can be removed by dilute hydrochloric acid. When the initial concentration of hydrochloric acid is 6%, the liquid-solid ratio is 6:1, the temperature is 25℃ and the reaction time is 5 min, the desilication rate can reach more than 70%, the removal rate of iron and manganese is 40% and 60%, the loss rate of tantalum and niobium is about 10%, and the remaining silicon in desilication slag exists as quartz.

3) The iron and manganese components in tungsten slag can be removed by concentrated hydrochloric acid in depth, and the temperature and reaction time have a great influence on the loss rate of tantalum and niobium.Under the conditions of hydrochloric acid concentration of 22%, reaction time of 15 min, reaction temperature of 90℃ and acid dosage as the theoretical dosage, the removal rates of iron and manganese can reach 98.01% and 98.71% respectively, and the recovery rates of tantalum and niobium are 92.67% and 90.13% respectively, achieving good tantalum and niobium enrichment effects. The main composition of the enriched slag is Si O2.

4) The recovery rates of tantalum and niobium were 86.57% and 82.48%, and the content of tantalum and niobium reached 2.81% and 9.23%, respectively, after the tungsten residue was desilication of rare hydrochloric acid and deep deferral and manganese in concentrated hydrochloric acid.