Table 3 13 C NMR chemical shift assignment range of lignin pyrolysis oil based on the chemical shift database created in our previous work
From: The use of combination of zeolites to pursue integrated refined pyrolysis oil from kraft lignin
Functional group | Integration region (ppm) | |
|---|---|---|
Carbonyl or Carboxyl bond | 215.0 – 166.5 | |
Aromatic C-O bond | 166.5 – 142.0 | |
Aromatic C-C bond | 142.0 – 125.0 | |
Aromatic C-H bond | 125.0 – 95.8 | |
Aliphatic C-O bond | 95.8 – 60.8 | |
Methoxyl-Aromatic bond | 60.8 – 55.2 | |
Aliphatic C-C bond | General | 55.2 – 0.0 |
Methyl – Aromatic (CH3-Ar) | 21.6 – 19.1 | |
Methyl – Aromatic at ortho position of a hydroxyl or methoxyl group (CH3-Ar’) | 16.1 – 15.4 | |