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A modified xanthate compound similar to xanthogen formates, S-benzoyl O-isobutyl xanthate (BIBX), was designed by introducing a carbonyl and a benzyl group into the xanthate structure. The preparation, recovery performance, and mechanism of adsorption of this compound to chalcopyrite is discussed. BIBX was synthesized using a one-pot approach with superior efficiency, which has important commercial implications. BIBX’s performance in the recovery of and mechanism of adsorption to chalcopyrite was investigated via flotation tests, adsorption quantity measurements, FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations. The results show that BIBX displays a substantially stronger collecting ability toward chalcopyrite than sodium isobutyl xanthate and O-isopropyl-N-ethylthionocarbamate. Moreover, BIBX displays superior selectivity for chalcopyrite compared to pyrite. The adsorption data indicate that BIBX can be applied under slightly acidic or alkaline conditions. BIBX behaves like a bidentate ligand, bonding with the chalcopyrite copper through the thiol sulfur and carbonyl oxygen atoms. These findings are supported by FTIR and XPS data. DFT calculations predict two distinct adsorption geometries, one with one Cu atom to form a six-membered ring complex and another with two Cu atoms to form an “irregular pentagon”-shaped complex.

This research reports a synthetic amino acid based zwitterionic poly(histidine methacrylamide) (PHisMA), which possesses switchability among zwitterionic, anionic, and cationic states, pH-dependent antifouling properties, and chelation capability to multivalent metal ions. The PHisMA polymer brush surface shows good antifouling properties to resist protein adsorption and bacterial attachment in its zwitterionic state at pH 5. This study also demonstrates that the solution acidity significantly affects the mechanical properties of PHisMA hydrogels. PHisMA hydrogels show higher viscoelastic properties and lower swelling ratios in the zwitterionic state at pH 4 and pH 5, compared to higher or lower pH conditions. It was discovered that PHisMA can chelate multivalent metal ions, such as Ca(2+), Mg(2+), Cu(2+), Ni(2+) and Fe(3+). This study provides us a better understanding of structure-property relationships of switchable zwitterionic polymers. PHisMA can potentially be adapted for a broad range of applications including wound care, water treatment, bioseparation, coating, drug and gene delivery carriers, etc.