In this study, a novel organic depressant maleyl 5-amino-1,3,4-thiadiazole-2-thiol (MATT) was synthesized and utilized as galena in the flotation separation of molybdenite galena. The results test indicated that MATT exhibited an excellent depression ability on but barely influenced pH range 6.0–11.0. Zeta potential suggested preferentially adsorbed surface. UV-visible spectroscopy analysis sto...