Water-enhanced Removal of Ciprofloxacin from Water by Porous Graphene Hydrogel

Abstract

An environmentally benign and efficient hydrothermal reduction method was applied for the preparation of three-dimensional (3D) porous graphene hydrogel (GH) adsorbents. The physicochemical properties of GH granules were systematically characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectra and Brunauer-Emmett-Teller (BET) method. GH granules showed an excellent adsorption capacity (235.6 mg/g) for ciprofloxacin via combined adsorption interaction mechanisms (e.g. π-π EDA interaction, hydrogen bonding, and hydrophobic interaction). Moreover, reducing the size of the hydrogels can significantly accelerate the adsorption process and enhance the removal efficiency of pollutants from aqueous solution. Water (more than 99 wt%) within hydrogels played a key role in enhancing adsorption performance. The GO hydrogels exhibited an excellent adaptability to environmental factors. These findings demonstrate that GH granules are promising adsorbents for the removal of antibiotic pollutants from aqueous solutions.

Low-cost biochar derived from herbal residue: characterization and application for ciprofloxacin adsorption

“…7 and Table 2 demonstrate that the adsorption data can be described better by the Langmuir isotherm (R 2 , 0.999) than by the Freundlich isotherm (R 2 , 0.983), Temkin isotherm (R 2 , 0.983) or D-R isotherm (R 2 , 0.878). Similar results were reported for adsorption of persistent organic pollutants, antibiotics and other organic pollutants with carbonaceous materials, such as active carbon, biochar or carbon nanotubes (Carabineiro et al 2012;Zheng et al 2013;Essandoh et al 2015;Ma et al 2015;Mita et al 2015).…”

Graphene Oxide-Gallic Acid Nanodelivery System for Cancer Therapy

“…1(b)). An increase in the interlayer distance of GO (0.87 nm) might be due to the exfoliation of Gr layers and the formation of oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl [36], as well as the intercalated water molecules on the surface of GO interlayer’s [37, 38]. The inset shows the XRD patterns of pure GA with several intense and sharp crystalline peaks at 2 θ values of 16.22°, 25.36°, and 27.64°, corresponding to the characteristic of an organic molecule with crystalline property [39].…”

Applications of Graphene-Modified Electrodes in Microbial Fuel Cells

“…In the self-assembly process, the basal planes of GO sheets spontaneously aggregate due to the increased attractive interactions of the van der Waals forces, the hydrogen bond and the π-π stacking interaction from the carbon framework, and the weaker electrostatic interactions from the ionization of the oxygen-containing groups, resulting in an ideal construction of GH [4,61,62]. The gelation of the suspension of GO sheets can be triggered by many methods, such as by adjusting the pH value of the GO solution [50], adding crosslinking agents [63] or using chemical reduction methods [64].…”