Congo red eradication via efficient La-NiO-g-C3N4 nanocomposite from contaminated water
Laila S. Alqarni, Mohamed N. Goda, Mohammed Qasem Alfaifi, Musaad Aleid, Amani H. Ahmed, Abdullah Alsulami, A. Modwi
Abstract
• La-NiO-g-C 3 N 4 nanocomposite was fabricated via sol-gel and sonication green method. • Kinetic analysis revealed PSO model was more suitable for the experimental data. • CR dye adsorption fitted the Freundlich isotherm with a maximum q max of 339.8 mg. g -1 . • Nanocomposite exhibited reduction capacity about 8.7% after four adsorption cycles This study has been conducted for the removal of the toxic dye Congo red (CR), in which La-NiO-g-C 3 N 4 (LNCN) nanocomposite was fabricated via sol-gel and sonication green method. These composites were subjected to various analyses, where a small crystallite size of 20 – 34 nm and a large surface area of 116.08 m². g -1 were observed. The CR pigment adsorption results aligned with the Freundlich isotherm, exhibiting a maximum q max of 339.8 mg. g -1 as determined by the Langmuir model, whereas the adsorption kinetics followed the pseudo-second-order model with k 2 = 0.0104 mg. g -1 . min -1 and t 1/2 < 2 min. The LNCN nanocomposite exhibited a minimal reduction in its capacity to absorb CR dye, with a decrease of about 8.7% after four adsorption cycles. The proposed process for the uptake of CR dyes by the composite involved n – π interactions, π – π stacking, and hydrogen bonding. The findings demonstrated that the green-synthesized LNCN nanocomposites performed excellently in removing toxic dyes.