Fig. 1.
Materials used for sorption tests and their relative humidity
Table 1.
Results of GPC analysis of the lignin sample expressed in standard units
| Mn (PS standard) [g/mol] | Mw (PSstandard) [g/mol] | Mw/Mn |
|---|---|---|
| 2 710 | 5 970 | 2.20 |
Fig. 2.
MMD of lignin separated from black liquor
Fig. 3.
FTIR-ATR spectrum of lignin in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 4.
FTIR-ATR spectrum of lignin in the range 400-1500cm−1 before and after adsorption of zinc ions
Fig. 5.
FTIR-ATR spectrum of pine bark in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 6.
FTIR-ATR spectrum of chitosan in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 7.
FTIR-ATR spectrum of oat bran in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 8.
FTIR-ATR spectrum of rice husk in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 9.
FTIR-ATR spectrum of coconut fibre in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 10.
FTIR-ATR spectrum of pectins in the range 400-4000cm−1 before and after adsorption of zinc ions
Fig. 11.
FTIR-ATR spectrum of sodium alginate in the range 400-4000cm−1 before and after adsorption of zinc ions
Table 2.
Chemical composition of plant raw materials
| Content of analyzed fractions [%] | ||||
|---|---|---|---|---|
| Rice husk | Pine bark | Coconut fiber | Oat bran | |
| Ash | 16.1 | 0.200 | 1.75 | 3.50 |
| Compounds extractable in ethanol | 1.97 | 7.85 | 1.24 | 3.09 |
| Cellulose | 44.3 | 25.6 | 40.7 | 5.61 |
| Lignin | 29.6 | 45.2 | 45.8 | 5.72 |
Fig. 12.
Yield of Zn ion removal (10 mg/dm3) from aqueous solutions for selected samples at pH 4 and 7
Fig. 13.
Concept of a sorption column composed of 3 types of bed (coconut fiber, lignin, pine bark) : for 1 g and 2 g, respectively
Fig. 14.
Effect of time and system pH on the sorption yield of zinc ions (10 mg/dm3)
Fig. 15.
Effect of time and system pH on the sorption yield of zinc ions (40 mg/dm3)
Fig. 16.
Effect of sorbent mass and system pH on the sorption yield of zinc ions
Fig. 17.
Effect of temperature and pH of the system on the yield of zinc ion sorption