水分子在铵伊利石表面吸附的密度泛函研究

发布时间：2018-06-14 07:09

  本文选题：水分子 + 铵伊利石　； 参考：《中国矿业大学学报》2017年06期

【摘要】：为实现黏土矿物颗粒界面疏水调控进而提高难沉降煤泥水处理效果,研究了水分子在铵伊利石表面的吸附机理.采用密度泛函理论方法对水分子在铵伊利石有晶格取代的(001)面和不存在晶格取代的(001)面上的吸附进行模拟计算.结果表明:水分子在(001)面吸附的最强活性点位于晶格取代原子Al成键的氧原子处,吸附最稳定的水分子垂直于有NH_4~+的硅氧环,并与NH_4~+和活性原子形成共2个氢键作用,吸附能为-0.67eV,且水分子有将NH_4~+拉离(001)面的趋势;水分子在(001)面的最稳定吸附主要是位于硅氧环空穴上方,水分子与表面氧原子形成3个氢键,吸附能为-0.41eV.2种最稳定吸附均存在微弱的静电吸附.选择合适的阳离子型疏水药剂与NH+4发生交换吸附,覆盖(001)面活性点,破坏水分子的稳定吸附,理论上可实现铵伊利石等黏土类矿物颗粒界面的疏水调控.
[Abstract]:The adsorption mechanism of water molecules on the surface of ammonium Illite was studied in order to regulate the interface of clay minerals and improve the treatment effect of refractory coal slime water. The density functional theory (DFT) method is used to simulate the adsorption of water molecules on the surface of ammonium Illite with lattice substitution and on the surface without lattice substitution. The results show that the strongest active point of adsorption of water molecules on the surface is located at the oxygen atoms which replace Al atoms in crystal lattice. The most stable water molecules adsorbed are perpendicular to the SiO2 ring with NH _ 4 ~, and form two hydrogen bonds with NH _ 4 ~ and active atoms. The adsorption energy is -0.67 EV, and the water molecule has the tendency of pulling NH _ 4 ~ D _ (001) from the surface, and the most stable adsorption of the water molecule on the surface is mainly located above the annular hole, and the water molecule forms three hydrogen bonds with the oxygen atoms on the surface. The adsorption energy is -0.41eV.2 the most stable adsorption exists weak electrostatic adsorption. The suitable cationic hydrophobic agent was selected to exchange and adsorb with NH _ 4, covering the active point of the surface of NH _ 4, which destroyed the stable adsorption of water molecules, and could realize the hydrophobic regulation of the interface of clay particles such as ammonium Illite in theory.
【作者单位】： 安徽理工大学材料科学与工程学院;新疆工程学院机械工程系;
【基金】：国家自然科学基金项目(51474011) 中国博士后基金项目(2014M561810) 安徽省自然科学基金项目(1508085QE90)
【分类号】：O647.3;TD94
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本文编号：2016590