Efficient Removal of Tetracycline from Aqueous Media with a Fe₃O₄ Nanoparticles@graphene Oxide Nanosheets Assembly

• Published in: International journal of environmental research and public health 2017-12, Vol.14 (12), p.1495
• Main Authors: Hu, Xinjiang, Zhao, Yunlin, Wang, Hui, Tan, Xiaofei, Yang, Yuanxiu, Liu, Yunguo
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; Anti-Bacterial Agents - chemistry; Antibiotics; Carbon; Composite materials; Data processing; Diffusion rate; Environmental conditions; Environmental effects; Environmental science; Fourier transforms; Graphene; Graphite; Graphite - chemistry; Humic acids; Humic Substances; Hydrogen ions; Hydrogen-Ion Concentration; Ionic strength; Kinetics; Magnetite Nanoparticles - chemistry; Nanoparticles; Osmolar Concentration; Oxides - chemistry; Particle size; Studies; Sulfuric acid; Temperature; Tetracycline - chemistry; Wastewater - chemistry; Wastewater treatment; Water Pollutants, Chemical - chemistry; Water Purification - methods
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph14121495

A readily separated composite was prepared via direct assembly of Fe₃O magnetic nanoparticles onto the surface of graphene oxide (GO) (labeled as Fe₃O₄@GO) and used as an adsorbent for the removal of tetracycline (TC) from wastewater. The effects of external environmental conditions, such as pH, ionic strength, humic acid (HA), TC concentration, and temperature, on the adsorption process were studied. The adsorption data were analyzed by kinetics and isothermal models. The results show that the Fe₃O₄@GO composite has excellent sorptive properties and can efficiently remove TC. At low pH, the adsorption capacity of Fe₃O₄@GO toward TC decreases slowly with increasing pH value, while the adsorption capacity decreases rapidly at higher pH values. The ionic strength has insignificant effect on TC adsorption. The presence of HA affects the affinity of Fe₃O₄@GO to TC. The pseudo-second-order kinetics model and Langmuir model fit the adsorption data well. When the initial concentration of TC is 100 mg/L, a slow adsorption process dominates. Film diffusion is the rate limiting step of the adsorption. Importantly, Fe₃O₄@GO has good regeneration performance. The above results are of great significance to promote the application of Fe₃O₄@GO in the treatment of antibiotic wastewater.