Measurements of the Molecular Diffusion Coefficient of Dimethyl Ether in Water at T = (313.15-373.15 K) and P = (0.69-2.76 MPa)

摘要

We report the first experimentally measured dataset on the molecular diffusion coefficient of dimethyl ether (DME) in water, at test temperatures ranging from 313.15 to 373.15 K and pressures ranging from 0.69 to 2.76 MPa. A new experimental setup was designed, fabricated, and validated based on the principle of constant-pressure diffusivity measurement. The sensitive pressure control system adopted in this study and the novel arrangement of the test fluids resulted in a highly accurate and precise experimental setup for measuring the diffusivity of low-soluble gases in liquids. The results indicate that the molecular diffusivity values are in the range of similar to 0.9-4.3 x 10(-9) m(2) /s, depending on the test conditions. The measured data find applications in the performance prediction studies of processes involving mass transfer between DME and water, such as wet extraction, direct DME fuel cells, and DME-aided oil recovery processes.