含氧官能团对煤表面电位的影响机理研究  

Influence mechanism of oxygen-containing functional groups on coal surface potential

作　　者：祖伟 李文渊 李智 ZU Wei;LI Wenyuan;LI Zhi(Yizhang Hongyuan Chemicals Co.,Ltd.,Chenzhou 423000,China)

机构地区：[1]宜章弘源化工有限责任公司,湖南郴州423000

出　　处：《煤炭工程》2024年第9期194-201,共8页Coal Engineering

摘　　要：为了研究含氧官能团对煤表面电位的影响机理,测定了含氧官能团不同的三种变质程度脱灰煤表面的Zeta电位,结合分子动力学模拟与密度泛函理论计算,揭示了煤表面的带电机理。结果表明,煤的表面电位与其表面含氧官能团数目相关,煤表面含氧官能团越丰富,其表面电位负值的绝对值越大;OH-在煤颗粒表面的优先吸附促进了含氧官能团中羧基、羟基基团中O—H结构的解离,从而使得煤表面带负电,随着煤变质程度的提高,煤中—COOH基团、—OH基团含量呈下降趋势,因此长焰煤、焦煤和无烟煤的负电位绝对值依次下降,最终引起颗粒与气泡间静电力的差异性。To study the influence mechanism of oxygen-containing functional groups on the surface potential of coal,the Zeta potential of three kinds of demineralized coal with different oxygen-containing functional groups was measured.Combined with molecular dynamics simulation and density functional theory calculation,the charging mechanism of coal surface was revealed.Studies have shown that the surface potential of coal is related to the number of oxygen-containing functional groups on its surface.The more abundant the oxygen-containing functional groups on the surface of coal,the more negative the surface potential.The surface charge of coal is the result of OH-preferential adsorption.OH-promotes the dissociation of O—H structure in carboxyl and hydroxyl groups on the surface of coal,so that the surface of coal is finally negatively charged.With the increase of coal metamorphism,the content of—COOH group and—OH group in coal shows a declining trend.Therefore,the absolute value of potential of long flame coal,coking coal and anthracite also decreases in turn,which eventually leads to the difference of electrostatic force between particles and bubbles.

关 键 词：低阶煤 含氧官能团 表面电位 分子模拟 浮选 

分 类 号：TD94[矿业工程—选矿]