Promoting effect of a cationic surfactant on low-rank coal flotation with oil collector: A molecular dynamics simulation study

摘要

The promoting effect of dodecyltrimethylammonium bromide (DTAB) on dodecane adsorption on a low-rank coal (LRC) surface was investigated by molecular dynamics simulations. The adsorption behavior and interaction energy of a LRC/dodecane and LRC/DTAB/dodecane system were studied. The dodecane molecules were difficult adsorb onto the LRC surface, as indicated by the adsorption configuration and concentration profiles. The head groups of DTAB~+ were adsorbed tightly onto the LRC surface, while the hydrophobic tails of DTAB~+ were exposed to the outside; this facilitated the adsorption of dodecane on the modified LRC surface. The interaction energy between dodecane and the LRC surface was increased due to the pre-adsorption of DTAB. The mobility of dodecane molecules was enhanced due to the attraction of the hydrophobic tails of DTAB~+ to the dodecane molecules. Klow-rank coal, cationic surfactant, flotation, molecular dynamics