Amelioration of mesoporous surface by varying concentration of ZnO to eliminate Methylene blue: characterization, kinetics modules and thermal parameter

Foud, Lalia; Emam, Abeer; Eldeen, Asmaa Kamal; Ibrahim, Marwa; Seif, Mona

doi:10.21608/idj.2019.64034

Amelioration of mesoporous surface by varying concentration of ZnO to eliminate Methylene blue: characterization, kinetics modules and thermal parameter

Document Type : Original Article

Authors

¹ 1- Department of Chemistry, Faculty of Science, Al-Azhar Univ. (Girl branch), Cairo, Egypt

² Department of Chemistry, Faculty of Science, Al-Azhar Univ. (Girl branch), Cairo, Egypt

³ Department of Chemistry, Faculty of Education, Ain Shams Univ., Roxy,Cairo, Egypt

10.21608/idj.2019.64034

Abstract

Adsorption assessment of ZnO-SiO₂ (ZSnc) by UV/Vis spectro-photometery was used to monitor the removal of the cationic dye (MB)from waste waters. Silica nanoparticles with a high adsorption capacitywere prepared by sol-gel method. SiO₂ modification was done bydissolving various ratios of zinc oxides at 10%, 30%, 50%, 70% and 90%.With a view to explain the adsorptive characteristics, they were portrayed by XRD, TEM, EDX, SEM, N₂adsorption/desorption isotherms techniques and FT-IR.
The results showed that anamorphous shape and porous structure were obtained by the sol-gel method. The calcination time of nanomaterial and concentration of MB have a significant effect on the adsorption efficiency. The equilibrium data were evaluated using the Langmuir and Freundlich isotherms in order to determine the best adjustment to the experimental data. Langmuir model has been the most appropriate for fitting the experimental data. Additionally, the adsorption kinetics is best described by the pseudo-second order model at a different concentration. Values demonstrated that the adsorption process is exothermic, spontaneous, and favorable. The results elucidated the potential for a new utilize of mesostructured nanomaterial as an active adsorbent.

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