A Study of Methylene Blue Dye Interaction and Adsorption by Monolayer Graphene Oxide

Abstract

The graphene oxide (GO) interaction with methylene blue (MB) cationic dye was studied in an aqueous solution at different pH during MB adsorption. The mutual interaction of MB with GO surface was studied and evaluated by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The π-π and electrostatic interaction of MB with GO surface are the main types of interactions, and the XRD data show the monomeric arrangement of MB cation with GO. The GO surface functional groups and point of zero charge (PZC) were determined by acid-base titration. Suitability of zeta-potential measurement and acid-base titration method was briefly discussed. The quality of prepared GO was evaluated by Raman spectroscopy, XRD, and atomic force microscope (AFM). The experimental adsorption equilibrium data were analyzed using Langmuir, Langmuir-Freundlich, Freundlich, and Temkin isotherms. The GO maximum adsorption capacity increases with higher pH, that is ascribed to the facile interaction of negatively charged GO with positively charged MB structure.

Effect of Surface Treatment of Nanocrystalline CeO2 on Its Dephosphorylation Activity and Adsorption of Inorganic Phosphates

“…For evaluation and description of the adsorption properties of prepared CeO 2 samples, the measured equilibrium data for inorganic phosphate adsorption were fitted by several mathematical models. Freundlich (F, eq ), Langmuir (L, eq ), Jovanović (J, eq ), and Henry (H, eq ) isotherms, which can be expressed in nonlinear form by eqs –, were used: q E = K F · c E n normalF q E = q M · K L · c E 1 + K L · c E q E = q M [ 1 − e − K normalJ c normalE ] q E = K HE · c E where q E is the phosphate amount adsorbed per unit weight of treated/not treated sample (mg/g), q M is the maximum adsorption capacity (mg/g), K F , K L , K J , and K H are the Freundlich (L/mg), Langmuir (L/mg), , Jovanović (L/mg), and Henry constant, respectively. The empirical Freundlich isotherm model is based on heterogeneous surface adsorption.…”

“…where q E is the phosphate amount adsorbed per unit weight of treated/not treated sample (mg/g), q M is the maximum adsorption capacity (mg/g), K F , K L , K J , and K H are the Freundlich (L/mg), Langmuir (L/mg), 50,51 Jovanović(L/ mg), 52 and Henry constant, respectively. The empirical Freundlich isotherm model is based on heterogeneous surface adsorption.…”

Valorization of Oil Palm Empty Fruit Bunch (OPEFB) as Membrane Polymer via Non-solvent Induced Phase Separation Method (NIPS) for Removal of Aqueous Contaminants

“…It might be due to electrostatic interaction between metal ion of Cr 3+ and hydroxyl groups of the membrane surface which is higher than Pb 2+ or Cu 2+ with hydroxyl groups. The adsorptive capacity of the membrane with some cationic species, such as heavy metal ions and cationic dye is enhanced via π-π electron donor-acceptor, electrostatic interaction and functional groups [39], [40], [41].…”

Loose and Encased Graphite for Methylene Blue Adsorption: Process Optimization and Principal Component Analysis

“…This value is low as compared to those of the modified/processed graphite-based adsorbents used for methylene blue removal. In particular, the adsorption capacity reported for expanded graphite and graphene oxide nanoparticles in methylene blue removal may reach a magnitude of a few hundreds to a few thousands (e.g., 250-1635 mg g -1 [28,[53][54][55][56]; see Tab. S2).…”