KINETICS OF CARBON-DIOXIDE AND METHANE HYDRATE FORMATION

Experimental data on the kinetics of carbon dioxide hydrate formation and its solubility in distilled water are reported. The experiments we re carried out in a semi-batch stirred tank reactor at nominal tempera tures of 274, 276 and 278 ii and at pressure ranging from 1.59 to 2.79 MPa for the kinetics experiments and at pressure ranging from 0.89 to 2.09 MPa for the solubility experiments. A minor inconsistency in the kinetic model developed by Englezos et al. (1987a) was removed and th e model was modified to determine the intrinsic kinetic rate constant for carbon dioxide hydrate formation. The same model was also used to re-determine the intrinsic kinetic rate constant for methane hydrate f ormation. The model is based on the crystallization theory coupled wit h the two-film theory for gas absorption in the liquid phase. The Henr y's? constant (H) and apparent dissolution rate constant (k(L)a) requi red in the model were determined using the experimental solubility dat a. The kinetic model describes;bes the experimental data very well. Th e kinetic rate constant obtained for the carbon dioxide hydrate format ion was found to be higher than that for methane.