文献类型：期刊文献

英文题名：Investigation of dodecylammonium adsorption on mica, albite and quartz surfaces by QM/MM simulation

作者：Liu, Zhen[1];Sun, Ze[1];Yu, Jian-Guo[1]

机构：[1]E China Univ Sci & Technol, Sch Resources & Environm Engn, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, Shanghai 200237, Peoples R China

年份：2015

卷号：113

期号：22

起止页码：3423

外文期刊名：MOLECULAR PHYSICS

收录：;EI(收录号：20151600766979);WOS:【SCI-EXPANDED(收录号:WOS:000364828200007)】；

基金：National Natural Science Foundation of China [grant number 21206038]; Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：QM simulation; QM; MM simulation; lithium recourses; mineral flotation

摘要：The absorption mechanisms of collector and mineral surface structures play important roles in studies of lepidolite flotation. In this work, quantum mechanics (QM) and hybrid quantum mechanics/molecular mechanics (MM) methods were implemented to investigate the flotation mechanisms of lepidolite from muscovite, quartz and albite. The crystal structures, electron density distributions, bonds and the densities of states of lepidolite were calculated and compared with those of muscovite. The adsorption structures and energies of monomer dodecylammonium (DDA) on the three different minerals were also calculated. The headgroup of the DDA cation was found to adsorb on the surface of minerals, with its hydrophobic tail stretching into the vacuum slab, approximately perpendicular to the surface. Simulation results indicate that the purity of fine lepidolite is limited by the existence of muscovite, due to their similarities in surficial structure and properties. Other gangues were found to be removed efficiently with the use of acidic conditions. The results are in good agreement with other experiments. Compared with simple MM simulations, the use of the QM/MM methods to investigate the adsorption on minerals without specific forcefield parameters was concluded to be a more accurate method to attain monomer surfactant-mineral adsorption energies.