吡啶类离子液体对低阶煤泥浮选的影响

Effect of pyridyl ionic liquids on the flotation of a low-rank coal slime

为探索吡啶类离子液体氯代十六烷基吡啶-水合物(cetylpyridinium chloride monohydrate,CCM)对低阶煤泥浮选的促进效果,通过煤泥浮选试验对不同浓度的CCM浮选指标进行比较。借助界面张力与傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR),揭示了CCM强化低阶煤泥浮选的作用机理。结果表明,CCM可显著改善低阶煤泥浮选效果,增加精煤可燃体回收率,但高浓度CCM会与脉石矿物发生非选择性吸附,增加精煤灰分,降低浮选完善度。界面张力结果表明,CCM能明显降低煤油与水溶液间的界面张力,促进捕收剂在矿浆中分散,降低药剂消耗。FTIR显示,CCM在静电力作用下吸附在低阶煤表面,降低了羰基、羧基、醚氧键类含氧官能团的数量,提高了煤表面疏水甲基、亚甲基数量,增强了低阶煤表面疏水性,优化了浮选效果。

In order to explore the effect of pyridine ionic liquid cetylpyridinium chloride monohydrate(CCM)on the flotation of low-rank coal slime,comparison of CCM flotation indexes of different concentration was conducted by slime flotation test.With the help of interfacial tension and Fourier transform infrared spectroscopy(FTIR),the mechanism of CCM enhanced low-rank coal slime flotation was revealed.The results demonstrate that CCM can significantly improve the floatation effect of low-rank coal slime and increase the recovery rate of cleaned coal combustible body.But high concentration CCM can produce non-selective adsorption with gangue minerals,increasing cleaned coal ash and reducing floatation perfection.Interfacial tension results show that CCM can significantly reduce the interfacial tension between kerosene and aqueous solution,promoting the dispersion of the collector in slurry,reducing drug consumption.FTIR results show that CCM was adsorbed on the surface of low-rank coal under the action of electrostatic force,which reduce the quantity of oxygen-containing functional groups of carbonyl,carboxyl and ether-oxygen bonds,increasing the quantity of methylene and methyl hydrophobic groups on the surface of coal,enhancing the hydrophobic property of the surface of low-rank coal,and optimizing the flotation effect.