Table 2: Functional
groups of E. nigrum biomasses and the corresponding infrared absorption
wave lengths.
Type
of Biomass |
Functional
group |
Type
of compound and vibration |
Frequency
(cm-1) |
Reference
frequency range (cm-1) |
Intensity |
Before Biosorption |
O-H |
Hydrogen bonded alcohols
& stretching |
(1) 3422 |
3200-3600 |
Strong and broad |
C-H |
Alkanes & stretching |
(2) 2933 |
2850-3000 |
Strong |
|
C=C |
Alkenes & stretching |
(3) 1639 |
1648-1638 |
Variable |
|
N-O |
Nitro & stretching |
(4) 1549 |
1550-1500 |
Strong |
|
-COO- |
Carboxylic acid &
bending |
(5) 1439 |
1449-1395 |
Medium |
|
C-N |
Amine & stretching |
(6) 1319 |
1080-1360 |
Medium |
|
C-O |
Alkyl aryl ether &
stretching |
(7) 1260 |
1000-1300 |
Strong |
|
C-O |
Primary alcohol &
stretching |
(8) 1081 |
1085-1050 |
Strong |
|
=C-H |
Alkene & bending |
(9) 931 |
675-1000 |
Variable |
|
C-H |
Aromatic (meta-substituted
benzene) & bending |
(10) 880 |
860-900 |
Strong |
|
C-H |
Aromatic (monosubstituted
benzene) & bending |
(11) 707 |
700-750 |
Strong |
|
C-X |
Chloroalkanes & bending |
(12) 540 |
540-760 |
Strong |
|
After modified with FeCl3
nanoparticles |
O-H |
Hydrogen bonded alcohols
& stretching |
(1) 3393 |
3200-3600 |
Strong and broad |
C-H |
Alkynes |
(2) 2933 |
2850-3000 |
Strong |
|
N-H |
Amine-amide I & bending |
(3) 1650 |
1650-1580 |
Medium |
|
N-H |
Amine-amide II & bending |
(4) 1554 |
1540-1640 |
Medium |
|
C=C |
Aromatic & stretching |
(5) 1452 |
1400-1600 |
Weak |
|
C-N |
Amine & stretching |
(6) 1319 |
1080-1360 |
Medium |
|
C-O |
Alkyl aryl ether &
stretching |
(7) 1261 |
1000-1300 |
Strong |
|
C-O |
Primary alcohol &
stretching |
(8) 1026 |
1085-1050 |
Strong |
|
=C-H |
Alkene & bending |
(9) 930 |
675-1000 |
Variable |
|
C-H |
Aromatic (meta-substituted
benzene) & bending |
(10) 880 |
860-900 |
Strong |
|
C-H |
Aromatic (monosubstituted
benzene) & bending |
(11) 707 |
700-750 |
Strong |
|
C-X |
Chloroalkanes & bending |
(13) 540 |
540-760 |
Strong |
|
Pretreated biomass after Th(IV) biosorption |
O-H |
Hydrogen bonded alcohols
& stretching |
(1) 3427 |
3200-3600 |
Strong and broad |
C-H |
Alkynes |
(2) 2926 |
2850-3000 |
Strong |
|
N-H |
Amine- amide I & bending |
(3) 1644 |
1650-1580 |
Medium |
|
N-H |
Amine- amide II & bending |
(4) 1542 |
1540-1640 |
Medium |
|
C=C |
Aromatic & stretching |
(5) 1453 |
1400-1600 |
Weak |
|
N-O |
Nitro & stretching |
(6) 1381 |
1345-1385 |
Strong |
|
C-N |
Amine & stretching |
(7) 1310 |
1080-1360 |
Medium |
|
C-O |
Alkyl aryl ether &
stretching |
(8) 1154 |
1000-1300 |
Strong |
|
C-O |
Primary alcohol &
stretching |
(9) 1032 |
1085-1050 |
Strong |
|
C-H |
Aromatic (meta-substituted
benzene) & bending |
(10) 860 |
860-900 |
Strong |
|
C-H |
Aromatic (monosubstituted
benzene) & bending |
(11) 740 |
700-750 |
Strong |
|
C-X |
Chloroalkanes & bending |
(12) 540 |
540-760 |
Strong |