## 4 Results and Discussion
Table 5 lists the fractional proton distribution of the three zones obtained from the spectra reported in Figures 7-9. As it can be seen, data on hydrogens distribution confirm the hypothesis: the distribution related to zone C is similar in all samples to that found for maltenes extracted according to the classical procedure results (see Table 4). The hydrogens distribution of zone B is of particular interest: paving grade 70/100 and 160/220 bitumen samples are both characterized by a high percentage of aromatic hydrogen (22.47% and 32.19%, respectively) and by the presence of olefinic peaks in the aliphatic region. Moreover, the broad band of aromatic hydrogen was replaced by a fine structure of well-defined aromatic zones and with not much overlapping peaks. This probably means that, for these two bitumens, zone B is characterized by the presence of simple polyaromatic compounds that originate a fine structure. Instead, the sample of Industrial bitumen presents only aliphatic hydrogen, which corresponds to proton on methyl and methylene groups and no appreciable line/band at the aromatic zone. Figure 6: The \({}^{1}\)H-NMR spectra of Industrial 2 160/220 bitumen in CCl\({}_{4}\): (**a**) neat bitumen; (**b**) maltene fraction; and (**c**) asphaltene fraction. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Bitumen**} & \multicolumn{3}{c}{**Hydrogen Distribution of Zone C \(\pm\)0.05**} & \multicolumn{3}{c}{**Hydrogen Distribution of Zone B \(\pm\)0.05**} \\ \cline{2-9}  & \(H_{\mathbf{\pi}}\) & \(H_{\mathbf{\alpha}}\) & \(H_{\mathbf{\beta}}\) & \(H_{\mathbf{\gamma}}\) & \(H_{\mathbf{\pi}}\) & \(H_{\mathbf{\alpha}}\)/\(H_{\mathbf{\alpha}}\) & \(H_{\mathbf{\beta}}\) & \(H_{\mathbf{\gamma}}\) \\ \hline Paving70/100 & 3.48 & 7.80 & 62.27 & 26.45 & 22.47 & 8.97/13.46 & 53.86 & 9.34 \\ Paving 160/220 & 8.49 & 7.30 & 58.73 & 25.47 & 32.19 & 11.95 H\({}_{\rm ol}\) & 45.91 & 9.94 \\ Industrial 160/220 & 8.75 & 13.48 & 60.73 & 17.04 & - & - & 92.62 & 7.38 \\ \hline \multirow{2}{*}{**Bitumen**} & \multicolumn{3}{c}{**Hydrogen Distribution of Zone A \(\pm\)0.05**} & \multicolumn{3}{c}{**Hydrogen Distribution of Zones B + A \(\pm\)0.05**} \\ \cline{2-9}  & \(H_{\mathbf{\pi}}\) & \(H_{\mathbf{\alpha}}\) & \(H_{\mathbf{\beta}}\) & \(H_{\mathbf{\gamma}}\) & \(H_{\mathbf{\pi}}\) & \(H_{\mathbf{\alpha}}\)/\(H_{\mathbf{\alpha}}\) & \(H_{\mathbf{\beta}}\) & \(H_{\mathbf{\gamma}}\) \\ \hline Paving70/100 & 17.43 & 14.38 & 55.53 & 12.66 & 19.17 & 17.69 & 52.27 & 10.57 \\ Paving 160/220 & 5.27 & 3.24 & 77.36 & 14.13 & 18.73 & 7.59 & 61.64 & 12.03 \\ Industrial 160/220 & 6.07 & 8.23 & 71.86 & 13.84 & - & - & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Fractional proton distribution of various zones scratched from the three bitumens by preparative TLC obtained from the \({}^{1}\)H-NMR spectra reported in Figures 7–9. Figure 7: The \({}^{1}\)H-NMR spectra of zone C obtained through a preparative TLC for the three bitumens: (**a**) paving 160/220; (**b**) paving 70/100; and (**c**) industrial 160/220. Figure 8: The \({}^{1}\)H-NMR spectra of zone B obtained through a preparative TLC for the three bitumens: (**a**) paving 160/220; (**b**) paving 70/100; and (**c**) industrial 160/220. Figure 9: _Cont._  
In the last zone A (the lower spot), the samples of the bitumen with the same grade showed a similar distribution of hydrogen, with the aliphatic part predominating with respect to the aromatic part, while the sample of the 70/100 bitumen is characterized by a higher percentage of aromatics than the others. It should be noted that, in Table 5, the distribution of \(H_{\rm ar}\) and \(H_{\rm ol}/H_{\rm\alpha}\) hydrogen of zone B for the industrial bitumen is not reported. The reason for the missing data is due to an \({}^{1}\)H experimental spectrum of this zone that does not present significant signals for these hydrogens. Important information can be extracted from Table 5; once again, the paving bitumen is poor in aromatic hydrogens and this lack can be found in both the maltene and resins.