Effect of n-tetradecane with or without n-heptadecane on equilibrium dissociation conditions of carbon dioxide hydrate

The isochoric stepwise heating method is used to study the effect of liquid hydrocarbon n-tetradecane and n-tetradecane/n-heptadecane on the equilibrium dissociation conditions of carbon dioxide hydrate. The addition of n-tetradecane or n-tetradecane/n-heptadecane reduces carbon dioxide hydrate phase equilibrium pressures. As the temperature increases, the promotion effect of the liquid hydrocarbons is more obvious. The promotion effect of n-tetradecane is stronger than that of the mixture of n-tetradecane and n-heptadecane at higher temperature. The quadruple point of carbon dioxide hydrate with the mixture of n-tetradecane and n-heptadecane (w = 0.3363) is almost the same as that of carbon dioxide hydrate in pure water. (C) 2020 Elsevier Ltd.