Kinetic and Isotherm Modelling of the Adsorption of Congo Red Dye onto NiFe2O4 and NiFe2O4 decorated Exfoliated Graphite

• Published in: IOP conference series. Materials Science and Engineering Vol. 991; no. 1
• Main Authors: Tan, L V, Thinh, P V, Tham, N T H, Sy, D T
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.12.2020
• Subjects: Adsorbents; Adsorption; Dyes; Graphite; Hazardous wastes; Isotherms; Mathematical models; Nickel ferrites; Parameters; Wastewater
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/991/1/012085

Adsorption using novel materials is a common and highly applicable process in remediation of hazardous dyes in wastewater. Herein, we attempted the synthesis of NiFe2O4 decorated-exfoliated graphite (EG@NiFe2O4), an inexpensive and environmental benign material, and analyzed the adsorption process of the as-synthesized adsorbent against Congo red dye. Kinetic of the adsorption was investigated using various models including first-pseudo kinetic, second-pseudo kinetic, Bangham model and Elovich model. Isotherm of the process was evaluated by Langmuir, Freundlich, Temkin and Dubinin − Radushkevich model. Lastly, thermodynamic parameters of the adsorption towards Congo red dye was calculated. Our findings indicated that kinetic and isotherm of the adsorption process of both adsorbents (EG@NiFe2O4 and NiFe2O4) could be well explained by the pseudo-second-order model (R2 > 0.99) and Langmuir isotherm (R2 =) respectively. In addition, kinetic parameters showed that EG@NiFe2O4 possesses greater adsorption capacity in comparison with NiFe2O4. Estimated thermodynamic parameters also indicated the spontaneous and endothermic adsorption (ΔG=) of the EG@NiFe2O4 composite against Congo red dye.