Increasing the biosorption capacity in removing Cd<SUP>2+</SUP> ions from synthetic aqueous solutions using N and M biosorbent, mechanism explanations, kinetics, thermodynamics, and desorption studies
The purpose of this study is to remove more Cd2+ ions from the aqueous solutions and increase biosorption capacity of Abies bornmuelleriana cones treated with 0.01 M NaOH. After biosorption, the capacities of normal Abies bornmuelleriana cones (N biosorbent) and modified Abies bornmuelleriana cones (M biosorbent) were compared. Additionally, the selectivity study was carried out in the presence of Hg2+ and Cd2+ ions. The removal mechanism of Cd2+ ions was explained using the zeta potentials, BET areas, total pore volumes, average particle diameters, FTIR, and SEM images-EDX analyses of N and M biosorbent after biosorption. The Langmuir isotherm for N and M biosorbents was selected as the ideal model since it had the greatest coefficient of determination (R-2) (0.99, 0.98) values and the lowest mean absolute errors (MAEs) (0.0070, 0.0018) and root mean squared errors (RMSEs) (0.0011, 0.0043). For the removal of Cd2+ ions using N and M biosorbents, the pseudo-second-order (P-S-O) model presented the highest R-2 (0.99, 0.99) values as well as the lowest MAE (0.015, 0.007) and RMSE (0.021, 0.01) values. Positive Delta H degrees for both biosorbents implies that the biosorption process is endothermic, whereas negative Delta G degrees shows that the biosorption process happens quickly at high temperatures. The augmentation in Delta S degrees with the temperature displayed the randomness of the biosorption. The Langmuir biosorbent capacities of N and M biosorbents were determined to be 18.4 and 22.1 mg g(-1), respectively. During six cycles, N and M biosorbents were regenerated with a 0.01 M HNO3 solution.
- Journal
- BIOMASS CONVERSION AND BIOREFINERY
- Year
- 2024
- Volume
- 14
- Issue
- 15
- Pages
- 17875-17889
- ISSN
- 2190-6815
- eISSN
- 2190-6823
- DOI
- 10.1007/s13399-023-04007-0
- WoS UID
- WOS:000946178000004