Abstract
Iron is an impurity widely occurred in sphalerite,and its effect on sphalerite flotation is complex.In this work,the effects of iron content and spin state on electronic properties and floatability of iron-bearing sphalerite are comprehensively studied using density functional theory Hubbard U(DFT+U)calculations combined with coordination chemistry flotation.The band gap of ideal sphalerite is 3.723 eV,and thus electron transition is difficult to occur,resulting in poor floatability.The results suggest the band gap of sphalerite decreases with increasing iron content.For low iron content,the decreased band gap facil-itates electron transition;at this case,Fe2+ in a high-spin state possesses one p electron pair,which can form a weak p-backbonding with xanthate,causing increasing floatability.However,for medium and high iron-bearing sphalerite,with the further decrease of band gap,Fe2+ is oxidized to Fe3+ due to elec-trochemical interaction,and hence p-backbonding is eliminated,leading to lower floatability of iron-bearing sphalerite,which is consistent with the flotation experimental results.This work could give a deeper understanding of how sphalerite flotation behaviors are affected by iron content.
基金项目
National Natural Science Foundation of People's Republic of China(NSFC52174246)
Interdisciplinary Scientific Research Foundation of Guangxi University(2022JCC016)
NETL
NSTL
维普
万方数据