非离子型复配捕收剂在低阶煤煤泥浮选综合指标上具有明显优势，但浮选效果易受非离子型表面活性剂类型影响。选用油酸二乙醇酰胺（ODEA）、聚氧乙烯单叔辛基苯基醚（OP-4）、失水山梨醇单油酸酯（Span80）分别与煤油混合制备复配捕收剂进行浮选试验，借助药剂分散性试验、接触角测试、X射线光电子能谱分析、分子动力学模拟等手段，研究了酯类、醚类、酰胺类非离子型复配捕收剂对长焰煤煤泥浮选的影响规律与强化机理。浮选试验结果表明，复配药剂具有较优捕收性和选择性，均可不同程度改善浮选效果，其中复配酯类Span80捕收剂浮选效果最佳，复配醚类OP-4捕收剂、复配酰胺类ODEA捕收剂效果相当，煤油效果最差。机理分析表明，3类非离子型表面活性剂均提升了长焰煤颗粒疏水性，但疏水强化程度因表面活性剂类型而异，主要体现在药剂对煤亲水位点覆盖与烃类油乳化分散的双重作用。由于氢键键合作用，Span80分子极性基团可有效覆盖煤粒表面极性位点，且分子疏水端向水相延伸，大幅增加了煤颗粒表面疏水性；ODEA分子同样可有效覆盖煤粒表面极性位点，效果较Span80分子稍差，但优于OP-4分子。三类非离子型表面活性剂均降低了煤油液滴尺寸，测定弦长集中在50～150 μm。复配酯类Span80药剂体系液滴数量最多，增加了其与煤粒疏水位点的接触时长与面积，更有利于浮选。OP-4相较ODEA，其乳化分散烃类油的优势在一定程度上弥补了其覆盖煤亲水位点的不足。

Compound collectors containing non-ionic surfactants have proven to be effective in low rank coal slime flotation but flotation performance often differs distinctly due to the presence of different non-ionic surfactants. In this paper,batch flotation tests were conducted using long-flame coal slime with the presence of kerosene composited with ODEA,OP-4,and Span80,respectively. Reagent dispersion tests,contact angle tests,X-ray photoelectron spectroscopy analysis and molecular dynamics simulation were used to interpret the mechanism underpinning the surfactant effect. Results show that all the compound collectors showed better collectivity and selectivity than kerosene,and improved the overall flotation performance. Kerosene+OP-4 and kerosene+ODEA had similar effects on flotation,while Kerosene+Span80 outperformed the other two compound collectors and kerosene. The mechanism analysis shows that all the nonionic surfactants improved the hydrophobicity of long flame coal particles,but the degree of hydrophobicity enhancement varied with surfactant type,mainly determined by the ability of the surfactant to cover the hydrophilic sites of the coal particle as well as to emulsify and disperse hydrocarbon oil. Due to hydrogen bonding,polar groups of Span80 molecules could effectively cover the hydrophilic sites of coal surface with its hydrophobic end pointing to the water phase,which greatly increased the surface hydrophobicity of coal particles. In comparison,ODEA molecules was not so good as Span80 but outperformed OP-4. Meanwhile,in the presence of the nonionic surfactants,the size of kerosene droplets decreased,and the measured chord length mainly fell between 50 and 150 μm. Compared to kerosene+OP-4 and kerosene+ODEA,the number of droplets was much greater in the system with kerosene+Span80,which favored the flotation by increasing the contact time and contact area with the coal. Interestingly,a greater capacity of OP-4 for emulsion and dispersion of hydrocarbon oils compensates for the poorer coverage of hydrophilic sites on the coal surface to some extent,which resulted in similar flotation test results using kerosene+OP-4 and kerosene+ODEA as observed.