Solubility of Carbon Dioxide in Poly(oxymethylene) Dimethyl Ethers

Experimental data on the solubility of carbon dioxide (CO₂) in poly(oxymethylene) dimethyl ethers (CH₃O(CH₂O)_nCH₃, OME_n) are presented for OME₂, OME₃, and OME₄. The total pressure was measured as a function of the liquid phase composition at 313.15 and 353.15 K for pressures up to 4.3 MPa in a high-pressure view-cell. Henry's law constants of CO₂ in OME₂, OME₃, and OME₄ are determined. They are similar for all studied OME and depend strongly on the temperature. The experimental data are modeled by the original perturbed-chain statistical associating fluid theory equation of state. As a basis, pure component models for OME were developed based on literature data on the liquid density and vapor pressure. The solubility of CO₂ in OME is successfully described using a group contribution scheme. The results show that OME are interesting candidates as physical absorbents for CO₂.