Experimental determination of hydrate dissociation conditions in CO2 + hexane + dodecane system,+1-propanol or plus tetra-n-butyl ammonium bromide

Hydrate dissociation conditions for one four-component system and two five-component systems, the CO2 + hexane + dodecane + water system, the CO2 + hexane + dodecane + 1-propanol + water system, and the CO2 + hexane + dodecane + tetra-n-butyl ammonium bromide (TBAB) + water system, were measured in the pressure range of (1.5 to 4) MPa and temperature range of (283 to 290) K at (0.1, 0.2 and 0.3) mass fraction of 1-propanol or TBAB. The experimental measurements were performed using the isochoric pressure-search method in a high pressure blind cell. The hydrate dissociation conditions (temperature and pressure) for the CO2 + hexane + dodecane + water system were compared with experimental data available in international literature were good agreement between the data was founded which indicates the viability of the experimental technique reported in this study. The experimental uncertainties were determined for temperature and pressure as combined standard uncertainties and are 0.16 K and 0.04 MPa, respectively. The relative standard uncertainty in composition was estimated to be 0.0014. In order to verify the reliability of the experimental data containing 1-propanol, a thermodynamic consistency test was performed. (C) 2021 Elsevier Ltd.

Automated summary

Experimental measurements of hydrate dissociation conditions were conducted for three multi-component systems, with good agreement found between the experimental data and literature data, indicating the viability of the experimental technique. The uncertainties in temperature and pressure were determined to be 0.16 K and 0.04 MPa, respectively, with a relative standard uncertainty in composition estimated to be 0.0014.