中国安全科学学报 ›› 2020, Vol. 30 ›› Issue (3): 21-27.doi: 10.16265/j.cnki.issn1003-3033.2020.03.004

• 安全工程技术 • 上一篇    下一篇

不同质量分数SDBS对煤体润湿性影响的分子模拟

李树刚1,2 教授, 郭豆豆1,2, 白杨1, 严敏1,2 副教授, 林海飞1,2 教授, 石钰1,2 副教授   

  1. 1.西安科技大学 安全科学与工程学院,陕西 西安 710054;
    2.教育部西部矿井开采及灾害防治重点实验室,陕西 西安 710054
  • 收稿日期:2020-01-05 修回日期:2020-03-10 出版日期:2020-03-28 发布日期:2021-01-26
  • 作者简介:李树刚(1963—),男,甘肃会宁人,博士,教授,博士生导师,主要从事煤与瓦斯安全共采等方面的研究。E-mail:lisg@xust.edu.cn。
  • 基金资助:
    国家自然科学基金资助(51734007,51674192,11802231);陕西省自然科学基金资助(2019JLP-02)。

Effect of SDBS of different mass fractions on coal's wettability by molecular simulation

LI Shugang1,2, GUO Doudou1,2, BAI Yang1, YAN Min1,2, LIN Haifei1,2, SHI Yu1,2   

  1. 1. College of Safety Science and Engineering, Xi'an University of science and Technology, Xi'an Shaanxi 710054, China;
    2. Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi'an University of Science and Technology, Xi'an Shaanxi 710054, China
  • Received:2020-01-05 Revised:2020-03-10 Online:2020-03-28 Published:2021-01-26

摘要: 为研究表面活性剂对煤体润湿性能的影响,选择十二烷基苯磺酸钠(SDBS)表面活性剂作为研究对象,采用Wiser煤化学结构模型,利用Materials Studio分子模拟软件,构建6种不同质量分数SDBS与水、煤共存的系统,分析系统吸附构型及能量变化,以及相对浓度分布、水分子均方位移(MSD)等。研究结果表明:SDBS分子的疏水烷基链吸附在煤表面,带苯环的亲水基团翘向水相,降低了水及煤的液-固界面张力;随着SDBS质量分数增加,系统总能量更低,SDBS与煤之间的相互作用能增大,分子间吸附作用更稳定,更有利于润湿煤;SDBS分子疏水烷基链的空间分布差异是影响煤润湿性能的主要原因之一;水分子扩散系数随着SDBS质量分数增加而增大,对煤体润湿性产生显著影响。

关键词: 十二烷基苯磺酸钠(SDBS), 煤润湿性, 分子动力学, 吸附构型, 相对浓度分布

Abstract: In order to study effects of surfactant on coal's wettability, with SDBS taken as research object, Wiser coal chemical structure model and Material Studio molecular simulation software were used to establish a system where SDBS of six different mass fractions coexisted with water and coal. Then, the system's adsorption configuration, energy changes, relative concentration distribution as well as mean square displacement (MSD) of water molecules were analyzed. The results show that hydrophobic alkyl chains of SDBS molecules are adsorbed on coal surface, and hydrophilic group with benzene ring warps to water phase, which reduces liquid-solid interfacial tension of water and coal. As mass fraction of SDBS increases, the system's total energy decreases, but interaction energy between SDBS and coal increases, indicating that adsorption between molecules is more stable and wettability is enhanced. Spatial distribution difference of hydrophobic alkyl chains of SDBS molecules is one of the main factors affecting wettability. Diffusion coefficient of water molecules increases along with the growth of SDBS mass fraction, which has a significant effect on wettability of coal.

Key words: sodium dodecyl benzene sulfonate (SDBS), coal's wettability, molecular dynamics, adsorption configuration, relative concentration distribution

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