关键词: 方锰矿　第一性原理　浮选行为　阴离子捕收剂

Abstract: Manganese is a critical strategic metal supporting the steel metallurgy and new energy industries,and its efficient
extraction is vital to national economic security. As a fundamental phase in manganese oxide systems,manganosite
(MnO) exhibits surface Mn2+ sites whose electronic properties decisively influence flotation separation efficiency,yet the atomic-
scale mechanisms remain unclear. In this study,first-principles calculations based on density functional theory were performed
using the GGA-PBESOL functional,a cutoff energy of 650 eV,and a 6×6×6 k-point sampling density to optimize computational
parameters. Bulk and (001) surface models of manganosite were constructed,and their electronic structures and flotation
mechanisms were investigated through Mulliken charge population,band structure,and density of states (DOS) analysis.
The results show that the optimized lattice parameters of manganosite exhibit only a 0. 84% deviation from experimental values,
with Mn—O bond populations of -0. 03 and bond lengths from 0. 220 to 0. 222 nm,indicating ionic bonding characteristics.
DOS analysis reveals that the valence band is dominated by O-2p orbitals,while the conduction band is primarily contributed by Mn-3d orbitals. Surface analysis demonstrates that the reduced coordination number of Mn2+ sites on the (001) surface
leads to electron delocalization,with unoccupied 3d orbitals facilitating p-d hybridization with anionic collectors,whereas O2-
sites exhibit weak affinity for cationic reagents due to the low activity of 2p orbitals. Flotation behavior predictions suggest that
under weakly acidic to neutral conditions,anionic collectors can form stable adsorption on Mn2+ sites via electrostatic interactions,
while alkaline conditions inhibit adsorption due to surface hydroxylation. This study provides atomic-scale theoretical insights
into the flotation separation of manganosite from gangue minerals and proposes the use of sulfonic/ phosphonic acid-based
collectors combined with activators to enhance selective adsorption efficiency.

Key words: manganosite,first-principles calculation,flotation behavior,anionic collectors