Removal of Malathion by Sodium Alginate/Biosilicate/Magnetite Nanocomposite as a Novel Adsorbent: Kinetics, Isotherms, and Thermodynamic Study

Abstract

Background: Organophosphorus pesticides are one of the widely consumed poisons in agriculture. The consumption of drinking water, which contains an excessive amount of poison, therefore, contributes to adverse health and hygiene outcomes in humans. Methods: In this study, a new sodium alginate/biosilicate/magnetite (SABM) nanocomposite made by the precipitation method was used to remove Malathion from aqueous solutions. The properties of MBSA were analyzed using XRD, SEM, EDX, and FTIR techniques. The possible impact of several parameters such as contact time, pH, initial Malathion concentration, temperature, and MBSA dosage on the adsorption process were investigated. The equilibrium isotherm and kinetic models were employed to evaluate the fitness of the experimental data. Results: The highest removal (94.82%) of MBSA was obtained at an optimum pH of 7, the contact time of 120 minutes, the adsorbent dosage of 4 g/L, Malathion concentration of 10 mg/L, and temperature of 318°K. The adsorption process followed the Freundlich isotherm model (R 2 = 0.999), which implied that the adsorption process of Malathion molecules onto MBSA might be mainly a multi-molecular layer. Conclusions: The results of this study showed that MBSA had a good removal efficiency, lower cost of processing, and as well as not producing substances harmful to the environment, which make it a promising adsorbent to remove Malathion from aqueous environments.

A Review of the Strategic Use of Sodium Alginate Polymer in the Immobilization of Microorganisms for Water Recycling

“…Other researchers have used Na-Alg in combination with catalysts to enhance the adsorption process [ 38 ]. For example, Lu et al [ 70 ] utilized sodium alginate/polyvinylpyrrolidone hydrogels; Hosseini et al [ 71 ] performed adsorption with Na-Alg in combination with biosilicate/magnetite nanocomposite for the removal of pesticide malathion; and Khiavi et al [ 72 ] combined Na-Alg with silica nanoparticles for aflatoxin reduction. Together, these studies highlight the promising applicability of Na-Alg in the context of environmental treatment, demonstrating its ability to address various challenges associated with the removal of aqueous contaminants.…”

“…Isotherms of adsorption are used to study and describe how solutes are adsorbed on a specific surface—such as that of an adsorbent—based on the solute concentration in the liquid phase [ 41 , 59 , 71 , 86 , 89 , 117 , 139 ]. The adsorbed contaminants are determined using Equation (1).…”

“…Unlike the pseudo-first-order model, this model suggests that the adsorption rate is proportional to the square of the solute concentration in the liquid phase. Equation (3) shows the pseudo-second-order kinetic model [ 67 , 71 , 150 , 151 ]. where q e , q t , and k 1 refer to the amount adsorbed at equilibrium (mg.g −1 ); t is the time at which the amount of contaminate adsorbed is assessed; k 2 is the rate constant; and q e is the adsorption capacity in equilibrium.…”

Synthesis and Characterization of Environmentally Friendly β-Cyclodextrin Cross-Linked Cellulose/Poly(vinyl alcohol) Hydrogels for Adsorption of Malathion

“…Human exposure to malathion can occur through various routes, such as agricultural application, consumption of treated produce, and contaminated drinking water. Malathion interferes with cholinesterase activity, leading to central nervous system disorders . Its moderate water solubility and the ineffectiveness of conventional treatment methods like sand filtration and coagulation for its removal highlight the need for more efficient techniques .…”

Removal of Malathion from Aqueous Solutions Using Dried Sludge Produced from Municipal Wastewater Treatment Plants in Daqhlia Government in Egypt

“…Some methods have been proposed to treat malathion, such as chemical oxidation processes, which have received attention due to high efficiency in chemical detoxification, efficiency in mineralization and detoxification [13]. Researchers using sodium alginate/biosilicate/magnetite (SABM) nanocomposite for removal of malathion [14].…”