Molecular dynamics study on wettability difference between lignite dust and silica dust
杨鹏王亚南王杰贾宏福杨凌云闫大鹤李文刚李梓萌
YANG Peng;WANG Yanan;WANG Jie;JIA Hongfu;YANG Lingyun;YAN Dahe;LI Wengang;LI Zimeng
山西华晋吉宁煤业有限责任公司中国矿业大学 (北京) 应急管理与安全工程学院
利用分子动力学模拟和量子化学方法,研究了褐煤煤尘与矽尘润湿机理的差异性;构建了水−表面活性剂−褐煤煤尘/矽尘模型,通过分子动力学模拟研究平衡后100 ps内各组分间相互作用能、径向分布函数(RDF)、均方位移(MSD)、自扩散系数(D)和相对数密度。结果表明:相对于矽尘,十六氨基三甲基溴化铵(CTAB)溶液与褐煤分子的相互作用能和自扩散系数较大、相对数密度峰值较高;基于褐煤煤尘与矽尘的静电势,SiO2的电势差变化幅度较大,可知活性剂吸附导致煤尘表面与水分子的电势差大小是影响表面润湿性差异的因素之一,但褐煤中官能团增加了分子间的相互作用,并在润湿过程中发挥着巨大作用。
In this paper, the differences in the wetting mechanisms of lignite dust and silica dust were investigated using molecular dynamics simulations and quantum chemical methods. A water-surfactant-lignite coal dust/silica dust model was constructed and the interaction energy, radial distribution function (RDF), mean square displacement (MSD), self-diffusion coefficient (D) and relative number density among the components within 100 ps after equilibrium were investigated by molecular dynamics simulations. The results show that the interaction energy and self-diffusion coefficient between cetyl trimethyl ammonium bromide(CTAB) solution and lignite molecules are larger and the peak value of relative number density is higher compared to silica dust; by comparing the electrostatic potential of lignite dust with that of silica dust, the magnitude of the potential difference of SiO2 varies widely, which shows that the size of the potential difference between the dust surface and water molecules due to active agent adsorption is one of the factors affecting the difference in surface wettability, but the functional groups in lignite increase the intermolecular interactions and play a significant role in the wetting process.
矽尘煤尘润湿性分子动力学量子化学粉尘防治
silica dust;coal dust;wettability;molecular dynamics;quantum chemistry;dust control
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会