{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T13:31:34Z","timestamp":1790947894026,"version":"4.1.0"},"reference-count":30,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2023,10,31]],"date-time":"2023-10-31T00:00:00Z","timestamp":1698710400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["52204270"],"award-info":[{"award-number":["52204270"]}]},{"name":"National Natural Science Foundation of China","award":["52074138"],"award-info":[{"award-number":["52074138"]}]},{"name":"National Natural Science Foundation of China","award":["202202AG050015"],"award-info":[{"award-number":["202202AG050015"]}]},{"name":"National Natural Science Foundation of China","award":["202001AS070030"],"award-info":[{"award-number":["202001AS070030"]}]},{"name":"National Natural Science Foundation of China","award":["202301AT070456"],"award-info":[{"award-number":["202301AT070456"]}]},{"name":"Yunnan Major Scientific and Technological Projects","award":["52204270"],"award-info":[{"award-number":["52204270"]}]},{"name":"Yunnan Major Scientific and Technological Projects","award":["52074138"],"award-info":[{"award-number":["52074138"]}]},{"name":"Yunnan Major Scientific and Technological Projects","award":["202202AG050015"],"award-info":[{"award-number":["202202AG050015"]}]},{"name":"Yunnan Major Scientific and Technological Projects","award":["202001AS070030"],"award-info":[{"award-number":["202001AS070030"]}]},{"name":"Yunnan Major Scientific and Technological Projects","award":["202301AT070456"],"award-info":[{"award-number":["202301AT070456"]}]},{"name":"Basic research project of Yunnan Provinc","award":["52204270"],"award-info":[{"award-number":["52204270"]}]},{"name":"Basic research project of Yunnan Provinc","award":["52074138"],"award-info":[{"award-number":["52074138"]}]},{"name":"Basic research project of Yunnan Provinc","award":["202202AG050015"],"award-info":[{"award-number":["202202AG050015"]}]},{"name":"Basic research project of Yunnan Provinc","award":["202001AS070030"],"award-info":[{"award-number":["202001AS070030"]}]},{"name":"Basic research project of Yunnan Provinc","award":["202301AT070456"],"award-info":[{"award-number":["202301AT070456"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Enhanced sulfurization has always been the focus of research on the flotation of copper oxide minerals. In this study, combined ammonium\u2013amine salts were innovatively applied to improve the sulfurization of azurite. Flotation tests were carried out to evaluate the promoting effect of ammonium\u2013amine co-activation on the sulfurization\u2013xanthate flotation of azurite, and the microstructure evolution of sulfurized products was investigated to reveal the mechanism underlying this promoting effect. Compared with single ammonium (amine) salt activation, ammonium\u2013amine co-activation improved the floatability of azurite to a greater extent, i.e., the flotation recovery increased by over 4 percentage points. ToF-SIMS, ICP-OES, FESEM-EDS, AFM, XRD, and UV-vis analyses indicated that ammonium\u2013amine co-activation combined the advantages of inorganic ammonium for buffering pH and organic amine for copper ion complexation, thus promoting the growth of sulfurized crystal products (covellite) and enhancing the adhesion stability of sulfurized products on azurite. Therefore, increasing amounts of copper sulfide components were generated under the ammonium\u2013amine\u2013Na2S system, promoting the adsorption of additional xanthate on azurite. This study provides theoretical support for the application of combined ammonium\u2013amine salts for the sulfurization flotation of copper oxide.<\/jats:p>","DOI":"10.3390\/molecules28217376","type":"journal-article","created":{"date-parts":[[2023,10,31]],"date-time":"2023-10-31T12:53:32Z","timestamp":1698756812000},"page":"7376","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Ammonium\u2013Amine Co-Activation: Promoting the Sulfurization of Azurite and Its Effect on Xanthate Adsorption"],"prefix":"10.3390","volume":"28","author":[{"given":"Chao","family":"Su","sequence":"first","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Resources, Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dianwen","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Resources, Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinpeng","family":"Cai","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Resources, Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peilun","family":"Shen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Resources, Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ding, Y., Lin, R., Xiong, S., Zhu, Y., Yu, M., and Duan, X. 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