低阶煤中含氧官能团含量对浮选吸附概率的影响规律

为了提高低阶煤的疏水性和可浮性,实现低阶煤的高效浮选提质,本研究用3种不同类别的表面活性剂(CTAB、SDS和Span-80)对平朔长焰煤和胜利褐煤煤样进行改性处理,采用离子交换法测定改性前后煤样中含氧官能团的含量,测定了各煤样在气泡上的吸附概率,并对表面活性剂改性低阶煤的规律和机理进行了分析,认为含氧官能团含量是影响煤的疏水性和可浮性的重要因素,通过表面活性剂改性可以对低阶煤表面的含氧官能团产生有效的掩蔽作用,提高低阶煤的疏水性,促进其在气泡上的吸附;氢键对表面活性剂在低阶煤表面的吸附起最主要的作用,表面活性剂极性端官能团的种类及其与煤中含氧官能团之间的氢键作用强弱对表面活性剂的改性效果起决定性作用。

Effect of oxygen-containing functional groups on the attachment probability of low rank coals in coal flotation

In order to improve the hydrophobicity and flotability of low rank coals and realize the efficient flotation of low rank coals,the Pingshuo long-flame coal and Shengli brown coal were surface modified with three types of surfactants which are CTAB,SDS and Span-80.The oxygen-containing functional groups in each modified coal were detected through ion exchange method,and the attachment probability of them were measured as well.The modifying rule of surfactants on low rank coals were analyzed and the mechanism was also discussed.It was found that the content of oxygen-containing functional groups was the most important factor that affected the hydrophobicity and flotability of low rank coals.The modification of low rank coals with surfactants could mask part of the oxygen-containing functional groups and improve the hydrophobicity of low rank coals as well as its attachment probability on bubbles.Hydrogen bonding is the main factor that make surfactants attach on the coal surface.The functional groups on the polar end of the surfactants and the strength of the hydrogen bond between them and the oxygen-containing functional groups on the coal surface play a decisive role in the surface modification.