Table 3 Relative distribution (%) of signal area over chemical shift regions (ppm) in ¹³ C-CPMAS-NMR spectra of the composts

Carboxylic-C

Phenolic-C

Aromatic-C

O-Alkyl-C

CH ₃ O/C-N

Alkyl-C

195 to 166 ppm

165 to 146 ppm

145 to 111 ppm

110 to 61 ppm

60 to 46 ppm

45 to 0 ppm