Abstract
Biodiesel was found to be a more effective collector on low-rank coal flotation than the common oily collectors (diesel and kerosene) in previous research. However, the micro-adsorption behavior of these collectors on the coal surface remains to be further explored. In the present work, the adsorption behavior of methyl laurate and dodecane, representing biodiesel and common oily collectors, was investigated using experimental and molecular dynamics (MD) simulation methods. The results of MD simulations showed that dodecane was difficult to diffuse on the surface of sub-bituminous coal and formed a spherical structure on the surface of sub-bituminous coal. Methyl laurate was adsorbed on the surface of coal via the head group (ester group), while the tail group (alkyl chain) was exposed to a liquid environment, forming a wider network structure on the coal surface. The above results, mainly attributed to methyl laurate, had a higher interaction with the sub-bituminous surface compared to dodecane. The self-diffusion coefficient results showed that the aggregate configurations of methyl laurate cause higher water mobility, which was more conducive to enhancing the hydrophobicity of the coal surface. The adhesion efficiency measurement and X-ray photoelectron spectrometer (XPS) analysis confirmed that methyl laurate could cover more oxygen-containing functional groups on the coal surface than dodecane, thus enhancing the hydrophobicity of coal. The results of simulations conformed to the experimental results.
Highlights
Low-rank coals, which account for more than half of the world’s proven coal reserves, are a premium fuel and industrial raw material with high reactivity [1,2].The processing and utilization of low-rank coal is of great help to the clean and efficient utilization of coal
In summary of the above studies, it can be seen that molecular dynamics simulation has attracted great attention in attempts to reveal the mechanism of collectors and minerals at the microlevel, but few studies have focused on the micro-adsorption behavior of the environment-friendly collector, fatty acid methyl ester, on the surface of low-rank coal
The results show that the methyl laurate with abovementioned molecular dynamics simulation
Summary
Low-rank coals (lignite and sub bituminous coal), which account for more than half of the world’s proven coal reserves, are a premium fuel and industrial raw material with high reactivity [1,2]. Biodiesel, composed of fatty acid methyl ester, is a biodegradable, renewable and nontoxic fuel, which can be used as an efficient collector for fine low-rank coal flotation [10,11]. Li et al [17] used molecular dynamics (MD) simulations to study the adsorption behavior of sodium oleate on siderite, hematite, and quartz in an aqueous environment. In summary of the above studies, it can be seen that molecular dynamics simulation has attracted great attention in attempts to reveal the mechanism of collectors and minerals at the microlevel, but few studies have focused on the micro-adsorption behavior of the environment-friendly collector, fatty acid methyl ester, on the surface of low-rank coal. The adsorption behavior of two collectors on the surface of low-rank coal was studied using the molecular dynamics method. The experiment was performed to verify the rationality of the simulation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
