We measure and model the effect of CO2 addition on equilibrium composition and volume expansion for solvent system 2-methyltetrahydrofuran (2-MTHF)/water. Our experimental data cover pressures from p = (0.03 to 3.51) MPa and temperatures from T = (293 to 363) K. Following the protocol we reported in Glass et al. (Fluid Phase Equilibria 2017, 433, 212-225), we apply infrared and Raman spectroscopy to monitor the organic and aqueous phases inline, respectively. CO2 solubility in binary system 2-MTHF/water is similar to that in tetrahydrofuran (THF)/water, but the effect of CO2 addition on the miscibility gap is lower on an absolute scale. We employ the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state (EOS) with physically inspired association schemes for the thermodynamic modeling of the chemical system. We additionally provide parameters for PC-SAFT with association schemes that are readily usable in the Aspen Suite. Ternary system CO2/2-MTHF/water is best described by a model with a total of six binary parameters yielding root-mean-square deviations (RMSDs) of 0.015 mol mol-1 for the organic phase and 0.002 mol mol(-1) for the aqueous phase. We use the EOS to predict the volume expansion in binary system CO2/2-MTHF. Calculated results are in good agreement with experimental data (RMSD = 5.1%). We further investigate the influence of water on volume expansion in ternary system CO(2/)2-MTHF/water in a theoretical study. The methods and data presented in this work enable the targeted utilization of green solvent system CO2/2MTHF/water on laboratory and processing scales.