ABSTRACT

The effect mechanism of mixing ratio on the adsorption behavior of low-rank coal surface using mixed collectors has not been systematically studied. In this study, dodecane (D) and n-valeric acid (N) were mixed into different collectors in different ratios, and their adsorption mechanism on the surface of LRC was studied by experiment and simulation calculation. The flotation results indicated that the sequence of the flotation clean coal yield was 8:2 > 6:4 > 5:5 > 7:3 > 9:1. The measurement results of the heat of adsorption, total organic carbon, and liquid phase contact angle all responded to the flotation results as a whole. The molecular dynamics simulation results revealed that when an appropriate ratio was used to form a mixed collector, the N molecules could make the D molecules form oil molecular layer thicken, thus increasing the hydrophobicity of the surface of the LRC molecules. The optimal mixing ratio could also create a large interaction energy between the mixed collector and LRC. Therefore, D and N need to be mixed at a proper ratio to maximize the LRC flotation efficiency.

摘要

混合比对混合捕收剂对低阶煤表面吸附行为的影响机理尚未系统研究。本研究将十二烷(D)和正戊酸(N)以不同比例混合到不同的捕收剂中，通过实验和模拟计算研究了它们在LRC表面的吸附机理。浮选结果表明，浮选精煤产量的顺序为8:2>6:4>5:5>7:3>9:1。吸附热、总有机碳和液相接触角的测量结果都对浮选结果作出了整体反应。分子动力学模拟结果表明，当采用适当比例形成混合捕收剂时，N分子可使D分子形成油分子层增厚，从而增加LRC分子表面的疏水性。最佳混合比还可以在混合收集器和 LRC 之间产生很大的相互作用能。因此，D 和 N 需要以适当的比例混合，以最大限度地提高 LRC 浮选效率。