Molecular Simulations of Fatty-Acid Methyl Esters and Representative Biodiesel Mixtures.
Despite the importance of fatty-acid methyl esters (FAMEs) as key components of various green solvents, detergents, plasticizers, and biodiesels, our understanding of these systems at the molecular level is limited. An enhanced molecular-level perspective of FAMEs will enable a detailed analysis of the polymorph and crystallization phenomena that adversely impact flow properties at low temperatures. Presented here, is the parameterization and validation of a charge-modified generalized amber force field (GAFF) for eight common FAMEs and two representative biodiesel mixtures. Our simulations accurately reproduce available experimental data (e.g. densities and self-diffusivity coefficients) and their trends, with respect to temperature and degree of unsaturation. Structural analyses from our simulations provide a more detailed picture of liquid-phase molecular ordering in FAMEs and confirm recent experimental hypotheses. This study provides a firm foundation to initiate further studies into the mechanisms that drive crystallization phenomena at the molecular level.
Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).
Vivek S
VS
Bharadwaj
Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).
Nathaniel M
NM
Eagan
Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).
Nicholas M
NM
Wang
Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).
Matthew W
MW
Liberatore
Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).
C Mark
CM
Maupin
biodiesel; fatty-acid methyl esters; generalized amber force field; molecular dynamics; molecular interactions