Synthesis of carboxyl‐functionalized magnetic nanoparticles for adsorption of malachite green from water: Kinetics and thermodynamics studies

• Published in: Journal of the Chinese Chemical Society (Taipei) Vol. 65; no. 8; pp. 940 - 950
• Main Authors: Mohammadi Galangash, Mohsen, Mohaghegh Montazeri, Mojgan, Ghavidast, Atefeh, Shirzad‐Siboni, Mehdi
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley‐VCH Verlag GmbH & Co. KGaA 01.08.2018; Wiley Subscription Services, Inc
• Subjects: Adsorbents; Adsorption; Aqueous solutions; carboxyl group; Endothermic reactions; Iron oxides; magnetic nanoparticles; Malachite green; Nanoparticles; recycling; Silicon dioxide
• ISSN: 0009-4536; 2192-6549
• DOI: 10.1002/jccs.201700361

Magnetic carboxyl‐coated silica iron oxide nanoparticles (Fe3O4@SiO2‐COOH NPs) were successfully synthesized, characterized, and then applied as a nano‐adsorbent for removal of malachite green (MG) from aqueous solutions. According to the experimental results, about 97.5% of MG could be removed from aqueous solutions using an adsorbent amount of 0.5 g/L at pH = 9 in 120 min. The kinetics and equilibrium adsorptions is well‐described by the pseudo‐second‐order kinetics and Langmuir model with the maximum absorption capacity of 263.16 mg/g, respectively. Thermodynamic studies showed that the adsorption of the hazardous MG dye was spontaneous and endothermic with a random process. Magnetic carboxyl‐coated silica iron oxide nanoparticles (Fe3O4@SiO2‐COOH NPs) were successfully synthesized, characterized, and then applied as a nano‐adsorbent for removal of malachite green (MG) from aqueous solutions. About 97.5% of MG could be removed from aqueous solutions using 0.5 g/L of the adsorbent at pH = 9 in 120 min.