Efficient removal of Pb(II) ions from aqueous solution by using a novel functionalized bio‐material with two tridentate coordinated units

Abstract

BACKGROUND Pb(II)‐containing wastewater causes serious pollution in our daily life. Adsorption is the technique most often used to remove heavy metals from aqueous solution. For improving the removal efficiency of Pb(II) ions from aqueous solution, adsorbent materials and the functionalization method of the adsorbent need to be further studied. RESULTS A novel Schiff's base functionalized bio‐material (DAS2‐AT) with two tridentate coordinated units was synthesized by the reaction of 2‐acetylthiophene and modified dialdehyde starch (DAS‐NH2) for the adsorption of Pb(II) ions from aqueous solution. Experimental results demonstrated that the DAS2‐AT exhibited high adsorption capacity and selectivity towards Pb(II), and the maximum adsorption capacity was up to 203 mg g−1. The adsorption isotherms and kinetic of Pb(II) ions on the DAS2‐AT were correlated well with the Langmuir isotherm model and Pseudo‐second‐order model. Moreover, thermodynamic analysis indicated that the adsorption process is spontaneous and endothermic. Desorption and regeneration experiments indicated that DAS2‐AT has good reusability. Besides that, the adsorbent displayed good affinity of DAS2‐AT towards Pb(II) ion in the presence of Cr(VI), Zn(II), and Ni(II) ions. CONCLUSION The bio‐adsorbent (DAS2‐AT) displayed good adsorption performance to remove Pb(II) ions from aqueous solution. DAS2‐AT gave a potential application as a low‐cost and effective adsorbent. © 2021 Society of Chemical Industry

Functionalization of a cast NaAl/binary ZnO/SiO2 nanohybrid with amine and Schiff base ligands as an adsorbent of divalent cations in water system

“…A higher adsorption capacity was achieved in a higher initial cation concentration. This can be due to the larger driving force under the high gradient of concentration to reduce the resistance of mass transfer between the cast nanohybrid phase and cationic aqueous phase leading to the more collisions of Cu 2+ and Ni 2+ cations and active sites of cast NaAl/aminated ZnO/Silica Schiff base nanohybrid (Abbasizadeh et al 2014, Guo et al 2021). Furthermore, the adsorption capacity of synthesized nanohybrid for Cu 2+ (74.8.9 to 80.8 mg/g) and Ni 2+ (40.6 to 45.0 mg/g) cations increased as temperature increased from 25.0°C to 45.0°C with an initial cation concentration of 100.0 mg/L.…”

“…Recently, Schiff base ligands have attracted much attention for heavy metal adsorption because of their nitrogen and oxygen donor atoms to form stable complexes (Betiha et al 2020, Guo et al 2021. For example, Betiha et al (2020), the synthesized Polyvinylpyrrolidone (PVP)-Aminopropyl-SBA-15 Schiff Base composite for Cu(II), Ni(II) and Pb(II) divalent cations with a maximum adsorption capacity of 128.0, 72.0 and 175 mg/g, respectively.…”

“…cast NaAl/aminated ZnO/Silica Schiff base nanohybrid were occupied with divalent cations; and above 90% of adsorption for Cu 2+ cation and 88% of adsorption for Ni 2+ cation occurred in the rst 90.0 min. This result may be due to the vacancy of nanohybrid sites for fast transfer of cations(Guo et al 2021, Tehrani et al 2017). After fast occupation of available binding sites, a slow transfer of cations occurred onto the remaining active sites; and nally, a saturated state was achieved.…”