## 3 Results and Discussion
### Thermal Behavior
#### 3.3.1 Pyrolysis
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{5}{c}{**Main Pyrolysis Parameters**} \\ \hline  & **Ma1** & **Ma2** & **Ma3** & **Ma4** \\ \hline Fast Pyrolysis initial \(T_{m}\) (\({}^{\circ}\)C) & 272.5 & 272.3 & 269.9 & 284.6 \\ Peak temperature \(T_{p}\) (\({}^{\circ}\)C) & 287.6 & 287.8 & 293.2 & 342.9 \\ Shoulder peak \(T_{s}\) (\({}^{\circ}\)C) & 343.5 & 342.4 & 339.0 & 293.7 \\ Pyrolysis finish \(T_{f}\) (\({}^{\circ}\)C) & 374.5 & 373.6 & 368.9 & 371.3 \\ DTG peak max (\%/min) & 20.23 & 21.24 & 16.76 & 16.62 \\ DTG shoulder (\%/min) & 14.25 & 14.53 & 16.26 & 14.68 \\ DTG mean (\%/min) & 2.08 & 2.09 & 2.05 & 2.00 \\ Fast Pyrolysis initial time \(t_{m}\) (min) & 12.40 & 12.39 & 12.31 & 12.88 \\ Peak time \(t_{p}\) (min) & 12.97 & 12.98 & 13.21 & 15.42 \\ Pyrolysis finish time \(t_{f}\) (min) & 16.97 & 16.93 & 16.69 & 16.81 \\ \(\Delta t_{1/2}\)(min) & 0.72 & 0.68 & 0.89 & 2.95 \\ \(P_{i}\) (\%/min\({}^{3}\times 10^{-3}\)) & 125.79 & 132.07 & 103.07 & 83.68 \\ \(P_{f}\) (\%/min\({}^{4}\times 10^{-3}\)) & 127.66 & 142.14 & 85.41 & 21.73 \\ \(P\) (\%/\({}^{\circ}\)C\({}^{3}\times 10^{-3}\)) & 16.13 & 17.08 & 13.58 & 11.92 \\ Residual Mass (\%) & 21.30 & 21.34 & 22.22 & 23.96 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Main pyrolysis parameters (inert atmosphere). Better characteristics can be observed for the residues mainly composed of corncob waste for pyrolysis [8], Ma1 and Ma2, due to the higher content in volatile compounds on a dry basis (Table 1) and the lower content in wastes (Table 3), whereas Ma4 waste has the worst characteristics as it is degraded in contact with the ground. Nevertheless, comparing similar wastes studied in other works, as in the case of rice husk with a residual mass of 36.92% [15], the good behavior of these wastes for this thermal process can be concluded. In Table 3, main pyrolysis indexes are shown. Concerning \(P_{i}\), the higher this value was, the easier it was for pyrolysis to take place in the waste, obtaining higher values for Ma1 and Ma2, 125.79 and 132.07%/min\({}^{3}\)\(\times\)\(10^{-3}\) respectively, than in the case of Ma3 and Ma4, 103.07 and 83.08%/min\({}^{3}\)\(\times\)\(10^{-3}\) respectively. Regarding the \(P\) index, higher values were observed for Ma1 and Ma2, 16.13 and 17.08%/\({}^{5}\)C\({}^{3}\)\(\times\)\(10^{-3}\), respectively, with a value of 13.58 and 11.92%/\({}^{5}\)C\({}^{3}\)\(\times\)\(10^{-3}\) for Ma3 and Ma4, respectively. This fact implies that the residues with a higher proportion of corncob waste had a lower peak temperature and, therefore, the pyrolysis process started earlier [31]. With regard to the \(P_{f}\)index, higher values were observed in Ma1 (127.66%/min\({}^{4}\)\(\times\)\(10^{-3}\)) and Ma2 (142.14%/min\({}^{4}\)\(\times\)\(10^{-3}\)) residues; this was due to the higher values of the peak max in the DTG curve and the lower values of time when the temperature peaks were reached. As in the case of the previous indexes, it can be concluded that these wastes are more suitable for energy use. Comparing the values of the \(P_{i}\), \(P\) and \(P_{f}\)index, it can be said that Ma1 and Ma2 residues, mainly composed of corncob waste, are better than Ma3 and Ma4 (which mainly contain corn stalk) for pyrolysis processes. Regarding the residues with corncob waste, Ma1 and Ma2, the separation of leaves makes no sense as, even though there is an increase in ash content, its separation would worsen the properties for pyrolysis. Moreover, and observing the values obtained, the negative effect of the long permanence of the waste on the soil (as in the case of Ma4) was clearly proved. In Figure 4, a comparison of the pyrolysis indexes is shown, indicating the relative percentage with respect to the highest value obtained for each index. In the graph shown, the residue with the best pyrolysis performance appears on the outside, whereas the residue with the worst characteristics appears in the innermost part of the geometric figure.