Basic Dye Adsorption onto Clay/MnFe₂O₄ Composite: A Mechanistic Study

Abstract

Native, HCl pretreated clay and MnFe2O4/clay composite were investigated as an adsorbent for crystal violet (CV) removal. The adsorption behavior of dye was studied in batch experiments as a function of contact time, adsorbent dose, pH, dye initial concentration and temperature. The medium pH 8, contact time 30 min, MnFe2O4/clay composite dose 0.05 mg/L, temperature 35 °C and 100 mg/L dye initial concentration furnished maximum CV adsorption. Adsorption data fitted well to the Langmuir isotherm model and maximum CV dye adsorption capacity of composite was 49.74 mg/g. The thermodynamic parameters revealed that the adsorption process of CV was exothermic and spontaneous in nature. CV adsorption followed the pseudo second order kinetic model. MnFe2O4/clay composite exhibited good CV adsorption capacity and can be used as an alternative adsorbent for the removal of basic dyes from effluents.

Synergistic Degradation of Dye Wastewaters Using Binary or Ternary Oxide Systems with Immobilized Laccase

“…It is worth to mention that there are many reports about the removal of dyes from aqueous solutions by sorption on various materials with different efficiency. For example, Rehman adsorbed Alizarin Red S onto alumina with the efficiency of around 70% [12], while Kamaz, using activated sludge from municipal wastewater, adsorbed nearly 100% of Congo Red, Eriochrome Black T, and RBBR [38]. The results obtained by us allow to state that oxide materials can also be used for sorption of environmental pollutants such as dyes.…”

“…Moreover, they are not applicable on an industrial scale as they generate high costs. For example, the adsorption method is effective depending on the adsorbent and adsorbate; ion exchange is not effective for disperse dyes, during membrane filtration the production of huge amounts of sludge occurs and there is need to use sophisticated equipment and high costs as a result of electricity consumption [10][11][12][13][14][15]. Thus, more and more interest is aroused by enzymes as a way of removing dyes from water.…”

Kinetics, Isotherm, Thermodynamics, and Recyclability of Exfoliated Graphene-Decorated MnFe2O4 Nanocomposite Towards Congo Red Dye

“…Among these, multiferroic nanomaterials (e.g., MFe 2 O 4 , M stands for transition metals) have afforded an abundance of widely practical applications, hence, giving rise in research interests, especially in environmental remediation [5,6]. With their outstanding properties in inherent structure, such as excellent magnetism for easy separation, high chemical stability, and tunable production in both laboratory scale and industrial scale, many studies focused on ferrites and their modified compounds on the removal and degradation of contaminants [7][8][9]. Among these emergent pollutants [10][11][12], however, synthetic dyes (e.g., Congo red, CR) have been considered as potential carcinogenic chemicals because they can contain several toxic functional groups and nondegradable skeletons including amine, imine, and benzene rings (Scheme 1), and hence, this topic have been paid much attention over the past decades [9,[13][14][15][16].…”

Preparation of NiFe2O4/polythiophene nanocomposite and its enhanced adsorptive uptake of Janus green B and Fuchsin basic from aqueous solution: Isotherm and kinetics studies

“…Nickel ferrite (NiFe 2 O 4 ) is an interesting soft magnetic material with notable magneto‐conductivity and low hysteresis loss . In recent past, ferrite‐based nanocomposites have drawn significant attention on account of their potential application as adsorbents for removal of dyes from wastewater . In context of polymer nanocomposites, conducting polymers are of considerable interest because of their high conductivity, environmental stability, cost effective monomer, ease of synthesis and unique physicochemical properties .…”