## 2 Experimental Methods  
The corrosive mediums were prepared in the laboratory with pro-analytics reagents and distilled water. The solutions that were used were the following:* Assay 1: 2% (_w/w_) NaCl with 1380 ppm CaCl\({}_{2}\) + CO\({}_{2}\);
* Assay 2: 2% (_w/w_) NaCl + CO\({}_{2}\);
* Assay 3: 2% (_w/w_) NaCl with 1360 ppm Na\({}_{2}\)CO\({}_{3}\) + CO\({}_{2}\);
* Assay 4: 2% (_w/w_) NaCl with 1.250 g CaCO\({}_{3}\) per liter of solution + CO\({}_{2}\);
* Assay 5: Solution with 1450 ppm NaCl + CO\({}_{2}\);
* Assay 6: Solution with 1380 ppm CaCl\({}_{2}\) + CO\({}_{2}\);
* Assay 7: Solution with 1360 ppm Na\({}_{2}\)CO\({}_{3}\) + CO\({}_{2}\);
* Assay 8: Solution with 500 ppm CaCl\({}_{2}\) + CO\({}_{2}\);
* Assay 9: Solution with 424 ppm Na\({}_{2}\)CO\({}_{3}\) + CO\({}_{2}\);
* Assay 10: Solution with 1.250 g CaCO\({}_{3}\) per liter of solution + CO\({}_{2}\). At first, NaCl-concentrated solutions were used, as found in the corrosive environment of the co-produced water with oil. Then, other salts were added. Finally, NaCl was removed from the system to assess how salts behaved without its influence. Regarding CaCO\({}_{3}\), a super-saturated solution was prepared; however, for the purpose of assessing the solubility of this salt under the conditions of the assay, it was considered as a concentration in a Ca\({}^{2+}\) solution equal to 180 ppm, in accordance with an estimate average from the work of [PERSON] and [PERSON] [18]. The graduated cylinders for dynamic conditions were manufactured using AISI 1040 steel bars, which were toned into rings with an outer diameter of 15 mm and 5.3 mm in height. The steel samples were water sanded with silicon carbide sandpaper with granulocyte values of 240, 320, 400, and 600. The graduated cylinders were cleaned with ethanol and air-dried upon each sandpaper change. Finally, they were cleaned with isopropyl alcohol and then dried. They were kept in a desiccator with silica gel until they were used. The equipment used for the measurements were a Metrohm potentiostat/galvanostat, PGSTAT204, with its respective NOVA 2.1 software. A PINE rotor stator was used in its ring configuration with a speed of 600 rpm. A 500 mL glass cell with 3 electrodes was used: a working electrode mounted on a rotating axis, a platinum counter electrode, and an Ag/AgCl (KCl 3M) reference electrode mounted in the front Luggin capillary. The methodology that was applied was linear polarization resistance (LPR), with a sweep speed of 0.1 mV/s. The solution was heated to \(65\pm 2\)\({}^{\circ}\)C, which required 1/2 an hour. Before performing the measurement, the carbon dioxide was immersed in the cell for 60 min. During this stage, all electrodes, except the working electrode, were immersed in the solution. After this period, the working electrode was immersed in the medium and, for an hour, the open circuit potential was measured. Then, the linear polarization-resistance test was performed using the open circuit potential ranging from \(-20\) mV to +20 mV. It should be noted that the measurements were performed in duplicate or until an acceptable repeatability was observed between them. The polarization resistance value (Rp) was used to calculate the corrosion rate, using the Stern-Geary [19] equation (Equation (1)):  
\[\mathrm{i_{corr}=\frac{B}{R_{p}}} \tag{1}\]  
\(\mathrm{i_{corr}=\text{ corrosion current [mA/cm${}^{2}$]}}\);  
B = Stern-Geary coefficient [mV];  
\(\mathrm{R_{p}=\text{Polarization resistance [f${}_{\text{C}}$]}}\). In this study, B equals 26 mV, given that it is a value that it is commonly accepted in CO\({}_{2}\) corrosion studies. It is noteworthy that it is not based on specific Tafel slopes, because the corrosion mechanism is not strictly controlled by the mass transfer [14]. The value of B was determined from an adjustment of the current density and weight loss measurements [20; 21; 22].