Table 1 FTIR spectra peaks assignment.
From: Adsorption of an anionic dye (Congo red) from aqueous solutions by pine bark
Wavenumber (cm−1) | Assignmentsa | ||
|---|---|---|---|
Before adsorption | After adsorption | ||
Natural pH | pH = 2 | ||
3402 | 3413 | 3410 | O–H and N–H stretching |
2924 | 2925 | 2925 | Aliphatic C–H stretching |
1736 | 1736 | 1736 | Ketone/aldehyde CO stretching |
1614 | 1616 | 1612 | C=O stretching |
1510 | 1510 | 1510 | Secondary amine groups |
1450 | 1450 | 1450 | Aromatic ring vibration |
1375 | 1375 | 1383 | C-H bending |
1317 | 1317 | 1315 | CH2wagging |
1267 | 1267 | 1267 | - SO3 stretching |
1157 | 1155 | 1155 | C–O–C asymmetrical stretching |
1063 | 1063 | 1063 | C–O, CC, and C–C–O stretching |
876 | 876 | 876 | Glycosidic linkage |
