Mesoporous Silica Modified with 2-Phenylimidazo[1,2-a] pyridine-3-carbaldehyde as an Effective Adsorbent for Cu(II) from Aqueous Solutions: A Combined Experimental and Theoretical Study

Abstract

In this study, we will present an efficient and selective adsorbent for the removal of Cu(II) ions from aqueous solutions. The silica-based adsorbent is functionalized by 2-phenylimidazo[1,2-a] pyridine-3-carbaldehyde (SiN-imd-py) and the characterization was carried out by applying various techniques including FT-IR, SEM, TGA and elemental analysis. The SiN-imd-py adsorbent shows a good selectivity and high adsorption capacity towards Cu(II) and reached 100 mg/g at pH = 6 and T = 25 °C. This adsorption capacity is important compared to other similar adsorbents which are currently published. The adsorption mechanism, thermodynamics, reusability and the effect of different experimental conditions, such as contact time, pH and temperature, on the adsorption process, were also investigated. In addition, a theoretical study was carried out to understand the adsorption mechanism and the active sites of the adsorbent, as well as the stability of the complex formed and the nature of the bonds.

Synthesis and Evaluation of Promising Antibacterial, Antifungal, and Antioxidant Activities for New Imidazo[1,2‐A]Pyridine‐Derived Imines

“…Once the reaction was complete, the resulting mixture was neutralized with a saturated solution of NaHCO 3 . The resulting precipitate was collected by filtration, washed with water and recrystallized in ethanol [24] …”

“…The resulting precipitate was collected by filtration, washed with water and recrystallized in ethanol. [24] White solid; mp 189-191 °C; yield 94 %; IR (KBr, cm À 1 ): 3100-2900 (CÀ H), 1640 (C=O), 1510 (C=N), 1420 (C=C); 1 H NMR (500 MHz, CDCl 3 ) δ 10.05 (s, 1H), 9.74 (dd, J = 2.1, 0.8 Hz, 1H), 7.74 (dd, J = 9.5, 0.8 Hz, 1H), 7.69 (m, 2H), 7.68 (m, 2H), 7.56 (dd, J = 9.4, 2.0 Hz, 1H); 13 C NMR (126 MHz, CDCl 3 ) δ 179. 36, 157.16, 146.15, 132.40, 131.93, 131.15, 127.00, 124.97, 123.92, 120.92, 117.83; m/z 335.95.…”