Use of Natural Safiot Clay for the Removal of Chemical Substances from Aqueous Solutions by Adsorption: A Combined Experimental and Theoretical Study

Abstract

The main objective of this work was to investigate the potential of Natural Safiot Clay (NSC), as an adsorbent for the removal of two cationic dyes such as Basic Blue 9 (BB9) and Basic Yellow 28 (BY28) from single and binary systems in aqueous solutions. For this, the effects of three factors controlling the adsorption process, such as initial dye concentration, adsorbent dose, and initial pH on the adsorption extent, were investigated and examined. The natural safiot clay was characterized using the following technique: energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), DRX, and Fourier transform infrared (FT-IR) and pH of the point of zero charge (pHZPC). Energy-dispersive X-ray spectroscopy results indicate high percentages of Silica and Alumina. FT-IR spectrum identified kaolinite as the major mineral phase in the presence of quartz, calcite, and dolomite. The quantum theoretical study confirms the experimental results, through the study of the global and local reactivity and the electrophilicity power of the dyes. The electrophilicity power of dyes affects the removal efficiency. The theoretical study proves that BB9 (ω = 6.178) is more electrophilic than BY28 (ω = 2.480) and more interactions with surface sites. The results of the molecular dynamics simulation indicate that the dyes are adsorbed parallel to the surface of natural Safi clay (kaolinite), implying the strong interaction with the kaolinite atoms. All the results of quantum chemistry calculations and simulations of molecular dynamics are in perfect agreement with the results of the experimental study.

Adsorption of Basic Yellow 28 and Basic Blue 3 Dyes from Aqueous Solution Using Silybum Marianum Stem as a Low-Cost Adsorbent

“…The pH zero-point charge (pH zpc ), one of the key variables influencing the adsorption procedure is crucial. The pH zpc values of the SLM Stem-Natural and SLM Stem-800 °C adsorbents were found using the drift method [ 66 , 67 ]. Accordingly, six 50 mL bottles were filled with solutions with initial pH (pHi) values ranging from 2 to 12 and 0.50 g of SLM Stem-Natural adsorbent was added.…”

“…To have information about the electrical charge interaction between the surfaces during adsorption, evaluating the optimum pH values in pH zpc is essential [ 67 ]. At pH < pH pzc , the surface charges of the sorbent are positive and sensitive to electrostatic interactions with anionic dye molecules.…”

“…To have information about the electrical charge interaction between the surfac ing adsorption, evaluating the optimum pH values in pHzpc is essential. [67] At pH < the surface charges of the sorbent are positive and sensitive to electrostatic inter with anionic dye molecules. If pH > pHpzc, the surface of the adsorbent becomes neg charged and can be used appropriately for the adsorption of cationic dyes such To have information about the electrical charge interaction between the surfaces during adsorption, evaluating the optimum pH values in pH zpc is essential [67].…”

Characteristics of glyphosate adsorption with biochar from young coconut waste

“…The Langmuir model describes biochar and glyphosate, which form a single layer in the adsorption mechanism. The energy created in this mechanism is not depending on the closure of the surface active sites because all sites are the same, and the biochar surface is homogenous [38]. At the same time, the Freundlich model explains that the heterogeneous biochar surface forms a multilayer between glyphosate molecules and the biochar surface.…”

High‐Efficiency Adsorptive Removal of Phenol from Aqueous Solution Using Natural Red Clay and ZnO Nanoparticles

“…Natural clays have been recognized for their exceptional properties such as high accessibility, non‐toxicity, abundant, simple recoverability, high surface area, cation exchange capacity and low cost [1a,23] . It has many applications in the field of environment as an adsorbent for the removal of CO 2 , [24] crystal violet dye, [23c] methylene blue dye, [25] fluoride and pathogen, [26] heavy metals [27]…”