## 2 Materials and Methods
### Procedures  
The CO\({}_{2}\) injection experiment which contained the swelling and vanishing interfacial tension (VIT) test was conducted at 131 \({}^{\circ}\)F and 158 \({}^{\circ}\)F working temperature and up to 2000 psia of working pressure. The parameters that resulted from the experiment were collected as pressure increased during injection. The compositional analysis obtained from the GC experiment of the original sample and remaining oil resulted from CO\({}_{2}\)-ethanol mixture injection at 131 \({}^{\circ}\)F and CO\({}_{2}\)-acetone mixture injection at 158 \({}^{\circ}\)F.  
The experiment used a combination of VIPS and GC apparatuses and consisted of two steps, i.e., the CO\({}_{2}\) injection experiment and the GC analysis. The former apparatus was invented by [PERSON] [12]. The VIPS apparatus was designed to be a multifunctional solution for several measurement methods such as PVT cell/synthetic live oil generation, swelling apparatus/viewing cell, high pressure and temperature viscosity measurement, and VIT/pendant drop, which can be used to measure several parameters simultaneously to determine the MMP. This apparatus can operate up to 5000 psi and 212 \({}^{\circ}\)F. The novel apparatus diagram is shown in Figure 1. \begin{table}
\begin{tabular}{c c} \hline \hline
**Properties** & **A1** \\ \hline API gravity & 42.2 \\ MW C\({}_{7+}\) & 135.85 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Crude oil sample properties. \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Component** & \multicolumn{2}{c}{**Mole\%**} \\  & & **Sample A1** \\ \hline Hydrogen sulfide & H\({}_{2}\)S & 0 \\ Carbon dioxide & CO\({}_{2}\) & 0.06 \\ Nitrogen & N\({}_{2}\) & 0.39 \\ Methane & C\({}_{1}\) & 13.88 \\ Ethane & C\({}_{2}\) & 1.75 \\ Propane & C\({}_{3}\) & 4.05 \\ Isobutane & iC\({}_{4}\) & 1.65 \\ n-Butane & nC\({}_{4}\) & 3.06 \\ Isopentane & iC\({}_{5}\) & 1.67 \\ n-Pentane & nC\({}_{5}\) & 1.57 \\ Hexane & C\({}_{6}\) & 2.7 \\ Heptane plus & C\({}_{7+}\) & 69.22 \\ \hline Total & & 100 \\ \hline
**Parameter** & \multicolumn{2}{c}{**Content (\%wt)**} \\ Asphaltenes & \multicolumn{2}{c}{-} \\ Aromatic & & 21.14 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Crude oil sample composition at reservoir condition and generalized characteristics. The swelling cell consisted of a set of see-through windowed high-pressurized cells built using a tubing-formed sapphire glass and thick stainless steel around the glass. This cell had an inner diameter of 0.82\" and height of 8.27\". Some part of the steel had holey windows to give a space for visual observation. For the cleaning step, the swelling cell and the lines flowed by oil were initially flushed using toluene to ensure that no residue was left inside. Before commencing the experiment, a heater was turned on for several hours to ensure all material had similar temperatures to air bath. First, the swelling cell was loaded with an amount of oil sample, and then the solvents were introduced for the solvent additive case. The solvent addition was set to be 10% of the oil weight. To complete the loading step, then, the cell was injected with a certain amount of CO\({}_{2}\) using a syringe pump (260D, Teledyne ISCO Inc., Lincoln, NE, USA), until a minimum desired pressure. The pressurizing process was conducted by either injecting CO\({}_{2}\) into the piston tube or introducing CO\({}_{2}\) into the swelling cell. After a certain pressure and temperature, the sample was circulated through Valve 8 to Valve 5 (refers to Figure 1) and flowed back into the swelling cell until an equilibrium condition was reached. The circulation was accomplished by two cycles of oil volume to meet stabilized pressure. The swelling factor and the viscosity were measured directly after equilibrium by using a height scale and viscosity probe, respectively. The viscosity was measured by using a vibrating-type viscometer at resonance frequency (MIVI 7000, Sofraser, Villemandeur, France).