Flotation activation mechanism of trithiocyanuric acid to malachite

Malachite is a typical refractory copper oxide mineral. In this paper, trithiocyanuric acid (TMT) was used as a novel activator for the activated flotation of malachite for the first time. The effect of TMT on the flotation behavior of malachite was studied and the activation mechanism was discussed. The flotation test results showed that TMT exhibited superior activation performance over sodium sulfide, achieving a high flotation recovery rate of 97.50 % at TMT 90 mg/L and pH 7. The contact angle confirmed malachite improved from 53.3° to 90.1° after TMT treatment, indicating enhanced hydrophobicity of the mineral surface. FTIR and EDS analyses provided clear evidence of chemical adsorption of TMT tautomers onto the malachite surface. SEM images further illustrated the presence of dense particles formed after TMT treatment. XPS revealed that TMT exhibited a strong adsorption effect on malachite, leading to an increase in copper sites and the formation of highly reactive Cu+. The activation mechanism was elucidated as the reaction between Cu sites on malachite and S and N atoms in TMT, forming Cu-S and Cu–N fractions crucial for activation. The high efficiency and low dosage of TMT make it a promising activator for malachite, offering a novel avenue for the effective recovery of malachite-type copper oxide ore resources.