Effect of leaching conditions on the elution of metals from denitration catalyst wastes

Abstract

Leaching of metallic species from denitration catalyst waste was performed at different leaching conditions using different solvents. The leaching efficiency of sodium percarbonate solution was higher than that of hydrogen peroxide (H2O2) or sodium carbonate solution. Under the optimal leaching conditions (1.0 mol kg[Formula: see text] sodium percarbonate, leaching temperature of 80[Formula: see text]C and leaching time of 5 h), the leaching rate was 90.7 ± 2.9% for W, 78.4 ± 4.1% for V and 8.6 ± 0.4% for Ti. The enhanced leaching ability of sodium percarbonate was due to the high affinity of the peroxo moiety (–O–O–) of H2O2, within the percarbonate, towards metallic ions and dissolution of titanium dioxide (TiO2) in the alkaline medium of carbonate.