Simulating the vapour-liquid equilibria of 1,4-dioxane

1,4-dioxane, a cyclic ether, is an emerging contaminant which is difficult to remove from water with conventional water treatment methods and resistant to biodegradation. Once a reliable force field is developed for 1,4-dioxane, molecular simulation techniques can be useful to study alternative adsorbents for its removal. For this purpose, we carried out Monte Carlo simulations in a constant volume Gibbs Ensemble to generate a force field which is capable of predicting the vapour-liquid coexistence curve and critical data of 1,4- dioxane. Results are given in comparison with experimental data and results from simulations with other force fields. Liquid densities and critical temperature are predicted in excellent agreement with experimental data using the new force field. At high temperatures, predicted vapour densities are in good agreement with experimental data, however, at lower temperatures the predicted vapour densities deviate about an order of magnitude from the experimental values. The critical density is slightly underestimated with our new force field. However, overall, the results of simulations with the new parameters give much better agreement with experimental data compared to the results obtained using other force fields.