Selective separation of chalcopyrite from pyrite using an acetylacetone-based lime-free process

•Acetylacetone (AA) can selectively collect chalcopyrite from pyrite without lime at pH 9.0.•Fe atoms on chalcopyrite surface interact with AA to form a six-membered ring complex.•The reactivity of Fe atoms on chalcopyrite surface is higher than that on pyrite surface.•The adsorption energy of AA on chalcopyrite is greater than that on pyrite.