Efficiency evaluation of Falcaria vulgaris biomass in Co(II) uptake from aquatic environments: characteristics, kinetics and optimization of operational variables

• Published in: International journal of phytoremediation 2024, Vol.26 (4), p.493-503
• Main Authors: Samimi, Mohsen, Mansouri, Ehsan
• Format: Article
• Language: English
• Subjects: Adsorption; Adsorption kinetics; Aquatic environment; Aqueous solutions; Biomass; Box-Behnken design; Cobalt; cobalt removal; Falcaria vulgaris; Falcaria vulgaris biomass; Functional groups; Heavy metals; Ions; Model accuracy; Optimization; Response surface methodology; Seeds; Statistical analysis
• ISSN: 1522-6514; 1549-7879
• DOI: 10.1080/15226514.2023.2250462

In the present research, the seeds of Falcaria vulgaris were extracted from the investigated environment and used for crop cultivation. This study has focused on the efficiency evaluation of Falcaria vulgaris biomass (FVB) in cobalt ions removal from aqueous solutions. The biosorbent was characterized using FTIR, BET, EDAX-EDS, and SEM. The optimal conditions were determined by the response surface methodology (RSM) based on a Box-Behnken design (BBD) model. The BBD model had   R 2 ,   R adj 2 and   R pred 2 values of 0.9919, 0.9774, and 0.8929, respectively. The cobalt removal under different conditions of the BBD model varied from 36.14% to 82.11%. Based on the numerical optimization of the quadratic model, the maximum cobalt removal at a biosorbent-to-metal ratio of 10:1, pH = 4.88 and contact time of 70 min was calculated at 80.941%. The high accuracy of the model in predicting the optimal conditions for cobalt adsorption by FVB was confirmed using statistical analysis and validation tests. The adsorption process of FVB also follows a pseudo-second-order kinetic model, which suggests that the rate-controlling step in cobalt removal is the chemical interaction between functional groups in FVB and Co +2 ions. This study shows that FVB, a low-cost biosorbent, can be a suitable candidate for removing heavy metals such as cobalt from aqueous solutions. In this research, the FVB biosorbent was prepared after seed extraction and planting of Falcaria vulgaris and then characterized and applied to cobalt adsorption. In addition, the operating parameters that affect metal adsorption were optimized using the RSM based on a BBD model. The FVB, in optimized conditions, as an efficient biosorbent, considerably has the potential for the adsorptive removal of metal ions from aquatic environments.