# Purification of Produced Water by Solvents to Enhance Oil Recovery and Reuse Separated Droplets
## 3 Results  
In Table 3, the concentrations of residual oil, \(C_{p}\), in ppm, after the treatment of produced water using the methodology previously described, are presented. Additionally, the percentages of oil recovery, denoted as \(R\), determined according to the following expression, are also presented:  
\[R=100\bigg{(}1-\frac{C_{p}}{150}\bigg{)}, \tag{2}\]  
\begin{table}
\begin{tabular}{c c c c c c} \hline
**Solvent** & **CAS Number** & **Molecular** & **Density** & **Boiling Point** & **Molecular Mass** \\  & [37] & **Formula** & **(g/cm\({}^{3}\))** & **(\({}^{\circ}\)C)** & **(g/mol)** \\ \hline
2-Phenylethanol & 60-12-8 & C\({}_{8}\)H\({}_{10}\)O & 1.020 & 218.2 & 122.16 \\
2-Propanol & 67-63-0 & C\({}_{3}\)H\({}_{5}\)O & 0.785 & 82.5 & 60.10 \\ Acetic acid & 64-19-7 & C\({}_{2}\)H\({}_{4}\)O\({}_{2}\) & 1.045 & 117.9 & 60.05 \\ Acetone & 67-64-1 & C\({}_{3}\)H\({}_{6}\)O & 0.790 & 56.0 & 58.08 \\ Acetonitrile & 75-05-8 & C\({}_{2}\)H\({}_{3}\)N & 0.787 & 81.6 & 41.05 \\ Benzene & 71-43-2 & C\({}_{6}\)H\({}_{6}\) & 0.879 & 80.1 & 78.11 \\ Butanone & 78-93-3 & C\({}_{4}\)H\({}_{8}\)O & 0.805 & 79.6 & 72.11 \\ Chloroform & 67-66-3 & CHCl\({}_{3}\) & 1.483 & 61.2 & 119.38 \\ Cyclohexane & 110-82-7 & C\({}_{6}\)H\({}_{12}\) & 0.778 & 80.7 & 84.16 \\ Cyclohexanone & 108-94-1 & C\({}_{6}\)H\({}_{10}\)O & 0.948 & 155.6 & 98.14 \\ Decyl oleate & 3687-46-5 & C\({}_{28}\)H\({}_{54}\)O\({}_{2}\) & 0.866 & 494.8 & 422.727 \\ Dichormethane & 75-09-2 & CH\({}_{2}\)Cl\({}_{2}\) & 1.325 & 39.75 & 84.93 \\ Dieethanolamine & 111-42-2 & C\({}_{4}\)H\({}_{11}\)N\({}_{2}\) & 1.097 & 268.8 & 105.14 \\ Diethyl ether & 60-29-7 & C\({}_{4}\)H\({}_{10}\)O & 0.713 & 34.6 & 74.12 \\ n-Butyl acrylate & 141-32-2 & C\({}_{7}\)H\({}_{12}\)O\({}_{2}\) & 0.890 & 145 & 128.17 \\ Diproylene glycol & 25265-71-8 & C\({}_{6}\)H\({}_{14}\)O\({}_{3}\) & 1.025 & 231.9 & 134.17 \\ Ethanol & 64-17-5 & C\({}_{2}\)H\({}_{6}\)O & 0.789 & 78.5 & 46.07 \\ Ethyl acetate & 141-78-6 & C\({}_{4}\)H\({}_{8}\)O\({}_{2}\) & 0.902 & 77 & 88.11 \\ Ethylene glycol & 107-21-1 & C\({}_{2}\)H\({}_{6}\)O\({}_{2}\) & 1.113 & 197.3 & 66.07 \\ Glycerin & 56-81-5 & C\({}_{3}\)H\({}_{8}\)O\({}_{3}\) & 1.261 & 290 & 92.09 \\ Isobutyl acetate & 110-19-0 & C\({}_{6}\)H\({}_{12}\)O\({}_{2}\) & 0.871 & 116.5 & 116.16 \\ Isooctane & 540-84-1 & C\({}_{8}\)H\({}_{18}\) & 0.692 & 99.2 & 114.23 \\ Isopropyl myristate & 110-27-0 & C\({}_{12}\)H\({}_{34}\)O\({}_{2}\) & 0.853 & 192.6 & 270.45 \\ Limonene & 138-86-3 & C\({}_{10}\)H\({}_{16}\) & 0.840 & 175.5 & 136.23 \\ Liquid paraffin & 8012-95-1 & Unspecified & 0.875 & 360 & Unspecified \\ Methanol & 67-56-1 & CH\({}_{4}\)O & 0.810 & 64.7 & 32.04 \\ N,N-Dimethyl formamide & 68-12-2 & C\({}_{3}\)H\({}_{7}\)NO & 0.944 & 153 & 73.09 \\ n-Butyl acrylate & 141-32-2 & C\({}_{7}\)H\({}_{12}\)O2 & 0.890 & 145 & 128.17 \\ n-Heptane & 142-82-5 & C\({}_{7}\)H\({}_{16}\) & 0.680 & 98 & 100.2 \\ Petroleum ether & 8032-32-4 & Unspecified & Unspecified & Unspecified & Unspecified \\ Polyethylene glycol 400 & 25322-68-3 & (C\({}_{2}\)H\({}_{4}\)O\({}_{n}\)H\({}_{2}\)O & 1.127 & \textgreater{}325 & \textgreater{}400 \\ Polypropylene glycol 2000 & 25322-69-4 & (C\({}_{3}\)H\({}_{6}\)O\({}_{n}\)H\({}_{2}\)O & 1.002 & \textgreater{}300 & \textgreater{}2000 \\ Propylene glycol & 57-55-6 & C\({}_{3}\)H\({}_{8}\)O\({}_{2}\) & 1.036 & 188.2 & 76.09 \\ Tetrachloroethylene & 127-18-4 & C\({}_{2}\)Cl\({}_{4}\) & 1.623 & 121.3 & 165.83 \\ Tetrahydrofuran & 109-99-9 & C\({}_{4}\)H\({}_{8}\)O & 0.889 & 65 & 72.11 \\ Toluene & 108-88-3 & C\({}_{7}\)H\({}_{8}\) & 0.864 & 110.6 & 92.14 \\ Vaseline (liquid) & 8009-03-8 & Unspecified & 0.840 & 198 & Unspecified \\ Xylene & 1330-20-7 & C\({}_{8}\)H\({}_{10}\) & 0.860 & 137–140 & 106.17 \\ \hline \end{tabular}
\end{table}
Table 2: _Cont._\(R\) is expressed as a percentage (%), and the higher its value, the more effective the oil recovery from produced water has been.