Adsorption difference of sodium alginate on marmatite (110) and galena (100): A DFT study

• Published in: Applied surface science Vol. 615; p. 156370
• Main Authors: Qiu, Hongxin, Deng, Jiushuai, Wu, Bozeng, Chen, Jianhua, Sun, Xiaohao, Hu, Mingzhen, Cai, Jiaozhong, Chen, Zherui, Zheng, Cheng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2023
• Subjects: Adsorption; Depressant; Galena; Marmatite; Sodium alginate; Depressant; Marmatite; Sodium alginate; Adsorption; Galena
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2023.156370

[Display omitted] •Study on adsorption difference of sodium alginate on galena and marmatite.•Iron atom is the main active site on the surface of marmatite.•The existence of iron enhances the bonding strength between SA and marmatite.•Fe2+ can form π-backbonding with SA by providing a pair of π electrons.•vdW, steric effects and weak covalent interactions dominate the adsorption of SA. In this study, density functional theory (DFT) was used to simulate the adsorption of sodium alginate (SA) on the surface of sphalerite, marmatite (110), and galena (100). The results showed that SA was mainly adsorbed on the surface of sphalerite by van der Waals interaction and steric hindrance without iron substitution. However, the substitution of iron on the surface of sphalerite significantly increased the adsorption energy of SA. In particular, the substitution of a large amount of iron significantly changed the surface properties of sphalerite, and the adsorption of SA on the surface of sphalerite changed from physical to chemical adsorption. The results of a density of states comparative analysis, charge transfer, and coordination theory analysis also confirmed that the adsorption of SA on a marmatite surface was easier and more stable than that on galena or sphalerite. Overall, the high selectivity of SA is expected to make it a green depressant of marmatite.