## 4 Discussion  
To optimally interpret the outcomes pertaining to the solvent mixtures, it is imperative to scrutinize the equilibrium data plot for the systems in question, with particular emphasis on the impact of environmental pressure during the evaporation process. A wealth of azeotropic information under varying pressure conditions is documented in the literature (Table 2). Each condition is delineated with corresponding azeotropic pressure (P\({}_{\text{AZ}}\)), azeotropic temperature (T\({}_{\text{AZ}}\)), and composition, which is frequently reported in terms of mole ratio or weight percentage. In this research, compositions are rendered in volume percentage (% v/ v) to facilitate ease of discussion. The azeotropic data documented in the literature exhibit variability even under identical boiling pressures at 760 mmHg. \begin{table}
\begin{tabular}{c c c c c} \hline
**Mixture** & **Initial Mixture** & **Mass Loss in** & **\% v/v of** & **Increase or** \\
**Components** & **\% v/v of** & **the Sample** & **Component A** & **Decrease in** \\  & **Component A** & **(\% m/m)** & **after Evaporation** & **Component A** \\ \hline  & 6.9 \(\pm\) 0.1 1  & 65.5 \(\pm\) 0.1 1  & 5.0 \(\pm\) 0.3 2  & decrease \\  & 8.2 \(\pm\) 0.1 1  & 48.7 \(\pm\) 0.1 2  & 7.0 \(\pm\) 0.4 2  & decrease \\  & 9.5 \(\pm\) 0.1 1  & 51.6 \(\pm\) 0.1 2  & 7.8 \(\pm\) 0.1 2  & decrease \\ (A) isopropanol & 10.5 \(\pm\) 0.1 1  & 51.8 \(\pm\) 0.1 2  & 12.3 \(\pm\) 0.1 2  & increase \\ (B) n-hexane & 11.5 \(\pm\) 0.1 1  & 50.9 \(\pm\) 0.1 2  & 12.7 \(\pm\) 0.3 2  & increase \\  & 12.4 \(\pm\) 0.1 1  & 65.4 \(\pm\) 0.1 2  & 14.6 \(\pm\) 0.9 2  & increase \\  & 19.6 \(\pm\) 0.1 1  & 66.2 \(\pm\) 0.1 2  & 42.6 \(\pm\) 0.9 2  & increase \\  & 24.8 \(\pm\) 0.1 1  & 66.2 \(\pm\) 0.1 2  & 57.8 \(\pm\) 1.9 2  & increase \\ \hline  & 27.9 \(\pm\) 4.2 2  & 47.3 \(\pm\) 0.1 2  & 21.1 \(\pm\) 4.5 2  & decrease \\  & 33.7 \(\pm\) 0.9 2  & 51.5 \(\pm\) 0.1 2 2  & 32.4 \(\pm\) 1.3 2  & decrease \\  & 34.4 \(\pm\) 1.0 2  & 36.7 \(\pm\) 0.1 2  & 31.3 \(\pm\) 0.9 2  & decrease \\ (A) 2-butanone & 34.4 \(\pm\) 1.0 2  & 83.3 \(\pm\) 0.1 2 2  & 18.1 \(\pm\) 1.5 2  & decrease \\ (B) cyclohexane & 37.3 \(\pm\) 1.2 2 2  & 47.9 \(\pm\) 0.1 2  & 37.2 \(\pm\) 0.9 2  & no change \\  & 38.7 \(\pm\) 1.0 2 2  & 47.1 \(\pm\) 0.1 2  & 38.2 \(\pm\) 0.5 2 2 2  & no change \\  & 46.9 \(\pm\) 0.2 2 2  & 81.4 \(\pm\) 0.1 2  & 61.2 \(\pm\) 1.5 2  & increase \\  & 48.0 \(\pm\) 2.4 2 2  & 48.5 \(\pm\) 0.1 2  & 62.0 \(\pm\) 8.6 2 2  & increase \\  & 58.0 \(\pm\) 0.1 2 2  & 45.6 \(\pm\) 0.1 2 2  & increase \\ \hline \end{tabular}
\end{table} 
Table 1: Evaporation studies of liquid phase composition of solvent mixtures at room temperature (20–23 \({}^{\circ}\)C) analyzed by gravimetry, GC analysis, or refractive index indicating direction of change in Component A. Values include \(\pm\) one standard deviation from 3 measurements. As demonstrated in the data in Table 2, the composition of the binary system isopropanolhexane is contingent upon the system's pressure, with a reported range spanning 199 to 845 mmHg. Consequently, this system is markedly influenced by environmental conditions, as the documented composition undergoes alteration within the range of 10 to 19.2% v/v over the recorded azeotropic pressures and temperatures. Within the realm of chemical industry literature, this phenomenon is designated a pressure-sensitive distillation system. With no documented data at ambient temperature and atmospheric pressure, the present investigation ascertained experimentally that the composition of the azeotrope approximates 10% v/v isopropanol, which just happens to match the data reported for 30 \({}^{\circ}\)C and 199 mmHg [17]. As such, the true room temperature azeotrope contains only about half as much isopropanol, the stronger solvent in the conservation applications in which it was used, which may therefore be ineffective at the cleaning being attempted.