Measurements of Molecular Diffusion Coefficient and Solubility of Dimethyl Ether in Bitumen at T = (323.15-383.15 K) and P = (0.69-2.76 MPa)

We report the first comprehensive data set on the molecular diffusion coefficient of dimethyl ether (DME) in bitumen at a temperature range of 70-110 degrees C and pressures up to 2.76 MPa. A new experimental setup was introduced that allows accurate and reliable measurements of equilibrium solubility and molecular diffusion coefficient of gases in liquids at high pressures and temperatures. The experimental data on diffusional mass transfer of dimethyl ether (DME) into the bitumen is utilized to estimate the molecular diffusion coefficient while taking the liquid swelling into account. The results show that the molecular diffusion coefficient of DME is in the range of similar to 0.2-2 X 10(-9) m(2)/s depending on the operating conditions and viscosity of the mixture. The measured data find applications in the design and optimization of solvent-aided thermal recovery of bitumen and heavy oil.