Preparation and Cationic Dye Adsorption of Novel Fe₃O₄ Supermagnetic/Thiacalix[4]arene Tetrasulfonate Self-Doped/Polyaniline Nanocomposite: Kinetics, Isotherms, and Thermodynamic Study

Abstract

In this study, a novel magnetically separable nanoadsorbent, namely, Fe 3 O 4 @PAmABAmPD-TCAS consisting of a magnetite core and conductive terpolymer of aniline/m-aminobenzoicacid/m-phenilendiamine shell which was self-doped by protonic acid of thiacalixarene tetrasulfonate pendent groups has been synthesized in a three step procedure. Adsorption features of the magnetic nanoadsorbent were evaluated by using methylene blue (MB) and malachite green (MG) as adsorbates. The isotherms, kinetics, and thermodynamics of the adsorption of MB and MG onto Fe 3 O 4 @PAmABAmPD-TCAS nanoadsorbent have been studied in various experimental conditions, i.e., initial dye concentration, contact time, solution pH, adsorbent dosage, and temperature. The obtained results fitted well to the Langmuir model and the kinetics of the adsorption process were found to follow the pseudo-second-order kinetics. The synthesized nanoadsorbent revealed improvements in terms of adsorption capacity for the dyes as a result of its high surface area and large amount of functional groups. The thermodynamic study was conducted by calculating a number of thermodynamic parameters such as the standard Gibbs energy (ΔG°), standard enthalpy (ΔH°), and standard entropy (ΔS°) changes. The high sensitivity of the magnetic nanoadsorbent to external magnetic field culminates in its efficient and easy separation.

Pollutant Diesel Soot Derived Onion-like Nanocarbons for the Adsorption of Organic Dyes and Environmental Assessment of Treated Wastewater

“…Free hydroxyl ions (OH − ) remained in the solution, thus there may be an interaction of MB dye molecules with negative OH − occurring, forming MB−OH complexation thus blocking the adsorption process on the surface of wsONC. So, it was found that at only pH 7−8, 62 the adsorption capacity of wsONC was at a maximum, where almost no interfering ions were present in the system and surface was negatively charged. Additionally, the effect of ionic strength on the adsorption capacity of wsONC was also studied by taking different concentrations of NaCl salt solution (Figure S2, Supporting Information).…”

Green synthesis and characterisation of L-Serine capped magnetite nanoparticles for removal of Rhodamine B from contaminated water

“…The Freundlich [32] isotherm can be applicable for modelling the adsorption of dye on heterogeneous surfaces and the linearised form of isotherm is expressed as logq e D logK f C ð1=nÞ Ã logC e (6) where K F (mg/g) is Freundlich constant representing the adsorption capacity at unit equilibrium concentration that is defined as the adsorption or distribution coefficient and 1/n is related to the adsorption intensity. The value of Freundlich constant 'n' is greater than 1.0, as shown in Figure 10(d), indicating that RhB favourably adsorbed on L-Ser capped Fe 3 O 4 NPs.…”

“…Instead, adsorption is promising technology for an effective treatment of polluted water due to it is low-cost, simply designed, easy to handle, and provides sludge-free output [4,5]. Activated carbon has been long known for an effective colour removal adsorbent, but its expensive operation cost unable to address for a wide range of consumers [6]. Hence developing of alternative adsorbents of less cost, ease of operation and simplistic design has been the focus of recent research.…”

Application of response surface methodology for ultrasound-assisted rapid ‎adsorption of meso-tetrakis(4-sulfonatophenyl) porphyrin by copper ‎nanowire-loaded in activated carbon: Characterization, equilibrium and ‎kinetic modeling

“…The slope of the plot of ln qe versus ε² gives K (mol 2 (kJ ) and the intercept yields the adsorption capacity; QS (mg g -1 ). The mean free energy of adsorption (E), for transfer of one mole of the target from infinity in solution to the surface of the solid was calculated from the K value using the following relation (Lakouraj et al, 2015):…”