Adsorptive removal of enrofloxacin with magnetic functionalized graphene oxide@ metal–organic frameworks employing D‐optimal mixture design

Abstract

A novel sorbent based on a mixture of magnetic functionalized graphene oxide and MOFs was developed to remove enrofloxacin (EFX) from water samples. The prepared sorbent was characterized using Fourier transform infrared spectra, scanning electron microscope images, and X‐ray powder diffraction pattern. The sorbent compositions were optimized by the mixture experimental design. Under the optimal condition, the percentages of each sorbent component, including triethylene tetramine‐functionalized graphene oxide (FGO), Fe3O4, and MOF‐5, were 40%, 21%, and 39%, respectively. Besides, the intraparticle diffusion and pseudo‐second‐order kinetic models can describe the EFX adsorption procedure because of two adsorption mechanisms of EFX on FGO and MOF‐5. A positive standard enthalpy of 49.80 kJ/mol indicated the EFX adsorption is endothermic with a chemisorption process. The negative values of ΔGo obtained in the range of −8.979 to −3.431 kJ/mol at all studied temperatures showed that the adsorption process was also spontaneous. The Langmuir and Freundlich isotherm models were analyzed with the partition coefficient to reduce bias in the isotherm model evaluation. The maximum adsorption capacity of 344.83 mg/g and a high partition coefficient of 17.42 g/L in an initial EFX concentration of 10 mg/L were obtained for the EFX removal. Practitioner points Magnetic functionalized graphene oxide @MOF‐5 as a sorbent for the enrofloxacin removal is synthesized. The percentage amount of each component of the sorbent is optimized using the D‐optimal mixture design. Adsorption mechanisms of enrofloxacin on magnetic functionalized graphene oxide @MOF‐5 are discussed. Thermodynamic parameters for the enrofloxacin adsorption with the sorbents are determined. Isotherm model for the enrofloxacin removal with the sorbent is investigated.

Pb (II) Adsorption over Activated Carbon Prepared from Cedrus Deodara Bark by Na2CO3 Activation: Optimal Design for Modelling and Process Optimization

“…During each of these experiments, 200 ml of 10 ppm Pb (II) solution at pH 7.0 was treated with constant mass of 0.1 g CDAC for a contact time of 180 mins during which the adsorption equilibrium was pre‐determined to be attained. Each experiment was replicated three times (n=3) and the mean values of the removal percentage (R%) was considered as response [17] . The coded and the actual levels of factors as well as the obtained responses for the adopted D‐optimal experimental design have been illustrated in Table 1.…”

“…Each experiment was replicated three times (n = 3) and the mean values of the removal percentage (R%) was considered as response. [17] The coded and the actual levels of factors as well as the obtained responses for the adopted D-optimal experimental design have been illustrated in Table 1. The table also illustrates the model summary statistics for different mathematical models including linear, 2FI, quadratic, cubic and quartic models.…”

“…In recent years, D-optimal design has been preferentially used in several studies because it not only provides the possibility of including categorical variables but also reduces the overall cost of the investigation since it requires significantly lesser number of experimental runs. [17,76] The mathematical relation between independent variables and the dependent variable may be expressed by following equation:…”

Synthesis of Magnetic Metal-Organic Frame Material and Its Application in Food Sample Preparation

“…The deposition and hydrophobic interaction between Fe3O4-NH2@MOF-235 and the analyte plays an important role in the adsorption process, and the maximum adsorption capacity can be reached Up to now, more and more studies on the development and application of MMOFs for analyzing pesticide and veterinary drug residues were reported. The detection targets also extended to fluoroquinolones [141,142], sulfonamides [143], ampicillin [144], nitroimidazoles [145], benzoylurea insecticides [146], tetracycline [147], triazine herbicides [148] et al, Duo et al, synthesized a novel, spinel-like magnetic metal-organic skeleton material (Fe 3 O 4 -NH 2 @MOF-235) by a two-step solvothermal method, and used as SPE adsorbent for simultaneous extraction and determination of five benzoyl urea pesticides in honey, fruit juice and tap water samples [149]. The deposition and hydrophobic interaction between Fe 3 O 4 -NH 2 @MOF-235 and the analyte plays an important role in the adsorption process, and the maximum adsorption capacity can be reached within 5 min.…”

Simultaneous removal of four aflatoxins using magnetic nanobentonite as a green and fast sorbent; Kinetic,termodynamic and isotherm investigation

“…The adsorption procedure is an economical, practical, and effective method to remove contaminants in water sources, foods, oils, etc. (Gordi et al 2020). The advantages of this technique for eliminating pollutants include low cost, simple operation, high efficiency, and availability of many types of sorbents without creating new pollutants (Ghorbani et al 2021, Shahmirzadi et al 2018.…”