scholarly journals Integrated experimental and theoretical insights for Malachite Green Dye adsorption from wastewater using low cost adsorbent

2021 ◽  
Author(s):  
EL-Shimaa Ibrahim ◽  
H. Moustafa ◽  
Sahar. A. El-molla ◽  
Shimaa Abdel Halim ◽  
Shaimaa Ibrahim
Keyword(s):  
Malachite Green ◽  
Rayleigh Scattering ◽  
Theoretical Calculations ◽  
Dye Adsorption ◽  
Experimental Results ◽  
Precipitation Method ◽  
Chemical Hardness ◽  
Optical Parameters ◽  
Cationic Form ◽  
Equilibrium Studies

Abstract Water pollution is one of the problems that threaten humanity, and to confront it with only experimental procedures is not enough. It is necessary to integrate both practical methods and theoretical calculations to achieve decontamination with the most accurate interpretation. Hence, discussing the experimental mechanism study of MG dye adsorption with the help of the application of DFT calculations is the main goal of this article herein. The experimental results affirmed that the preparation of γ-Al2O3 by precipitation method using (NH4)2CO3 improved the porosity, the surface capability, and the adsorbent capacities (qmax = 210 mg/g) at optimum condition compared with the previous studies. Kinetic and equilibrium studies referred that the adsorption follows the pseudo-second order model and Freundlich isotherm model, respectively. Also, the calculated and observed thermodynamic parameters exerted positive values of (ΔH°) and (ΔS°) which translates into endothermic process with increasing disorder of the system. Theoretical calculations at DFT- B3LYP/6-31G (d,P) level of theory were calculated to show the selectivity of using the cationic form of the Malachite Green (MG) in the experimental measurements to find interaction mechanism. The electronic structure and intramolecular charge transfer of (MG), its cationic form and the complex of MG-Al were investigated theoretically at the B3LYP/6-31 G (d,p) level of theory. The equilibrium geometries of (MG), its cationic form and the complex of MG-Al were determined, and it was found that these geometries are non-planar. The EHOMO and ELUMO energies can be used to calculate the global properties; chemical hardness (η), softness (S) and electronegativity (χ). The calculated nonlinear optical parameters (NLO) of the studied compounds; the electronic dipole moment (μ), first-order hyperpolarizability (β), the hyper-Rayleigh scattering (βHRS) and the depolarization ratio (DR)) showed promising optical properties. Finally, the computational and the experimental results indicated that the adsorption efficiency of MG from wastewater was directly associated with the dye electrophilicity power.

ADSORPTION OF MALACHITE GREEN DYE ON CLAY AND MODIFIED CLAY

2019 ◽  
pp. 445-451
Author(s):  
Violeta Rakić ◽  
Milena Miljković ◽  
Vojkan Miljković ◽  
Marjan Ranđelović
Keyword(s):  
Adsorption Capacity ◽  
Malachite Green ◽  
Dye Adsorption ◽  
Theoretical Models ◽  
Langmuir Model ◽  
Experimental Results ◽  
Textile Dye ◽  
Concentrated Solutions ◽  
Modified Clay ◽  
Malachite Green Dye

The goal of this study was to investigate the possibility of using natural materials based on clay and polysaccharides of carboxymethylcellulose as adsorbents for removing the textile dye malachite green from its solution. In this article, adsorption of dye on native clay and modified clay containing 3% carboxymethylcellulose was compared. The experimental results of dye adsorption with native and modified clay were interpreted using theoretical models of adsorption isotherms. The best match of the experimental results for native clay was achieved with the Langmuir model, and a slightly lower degree of correlation existed for the Freundlich's model. A good matching with the Langmuir's model indicates monolayer dye adsorption as well as certain energy homogeneity of the surface. After modification of the clay with carboxymethylcellulose, a better maching with the Freundlich's model was observed. This indicated that, as a consequence of the application of carboxymethylcellulose, the surface of the clay was changed in chemical and energy terms. The native clay had a lower adsorption capacity compared to clay modified with carboxymethylcellulose. The use of modified clay to remove the dye of malachite green was advisable in very concentrated solutions, because it showed obvious advantages compared to native clay.

Theoretical Framework of 1,3-Thiazolium-5-Thiolates Mesoionic Compounds: Exploring the Nature of Photophysical Properties and Molecular Nonlinearity

2020 ◽  
Author(s):  
Zeyu Liu ◽  
Shugui Hua ◽  
Tian Lu ◽  
Ziqi Tian
Keyword(s):  
Optical Properties ◽  
Rational Design ◽  
Rayleigh Scattering ◽  
Function Analysis ◽  
Theoretical Calculations ◽  
Photophysical Properties ◽  
Optical Nonlinearity ◽  
Nonlinear Properties ◽  
Photoelectric Performance ◽  
Wave Function Analysis

Inspired by a previous experimental study on the first-order hyperpolarizabilities of 1,3-thiazolium-5-thiolates mesoionic compounds using Hyper-Rayleigh scattering technique, we theoretically investigated the UV-Vis absorption spectra and every order polarizabilities of these mesoionic molecules. Based on the fact that the photophysical and nonlinear properties observed in the experiment can be perfectly replicated, our theoretical calculations explored the essential characteristics of the optical properties of the mesoionic compounds with different electron-donating groups at the level of electronic structures through various wave function analysis methods. The influence of the electron-donating ability of the donor on the optical properties of the molecules and the contribution of the mesoionic ring moiety to their optical nonlinearity are clarified, which have not been reported by any research so far. This work will help people understand the nature of optical properties of mesoionic-based molecules and provide guidance for the rational design of molecules with excellent photoelectric performance in the future.

Photocatalytic Activity of Fe-Doped ZnO/Montmorillonite Nanocomposite for Degradation of Malachite Green

2015 ◽  
Vol 827 ◽  
pp. 19-24 ◽  
Author(s):  
Nur Afifah ◽  
Nadia Febiana Djaja ◽  
Rosari Saleh
Keyword(s):  
Photocatalytic Activity ◽  
Malachite Green ◽  
Organic Dyes ◽  
Uv Light ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Resonance ◽  
Doped Zno ◽  
Co Precipitation

In this study, the photocatalytic activity of pure Fe- doped ZnO and Fe- doped ZnO/Montmorillonite nanocomposite has been investigated for the degradation of malachite green under UV light irradiation. Both photocatalysts were synthesized using co-precipitation method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier-transform infrared absorption, and electron spin resonance. The results showed that the photocatalytic efficiency is better in the presence of montmorillonite compared to pure Fe- doped ZnO. To detect the possible reactive species involved in degradation of organic dyes control experiments with introducing scavengers into the solution of organic dyes were carried out. It is found that electron plays an important role in the degradation of malachite green.

PERFORMANCE TEST AND HEAT RESISTANCE OF PHYSICAL AND CHEMICAL COATED IRON OXIDE BLACK PIGMENT

2021 ◽  
Author(s):  
KE YAN ◽  
CHUNYAN BAO ◽  
ZHENG WANG
Keyword(s):  
Iron Oxide ◽  
Heat Resistance ◽  
Performance Test ◽  
Reaction System ◽  
Experimental Results ◽  
Black Pigment ◽  
Precipitation Method ◽  
Inorganic Pigments ◽  
Oil Absorption ◽  
Light Fastness

The current development strategy of inorganic pigments is to develop technologies, such as high coloring ability, low oil absorption, easy dispersion, heat resistance, and nontoxicity. As the largest colored inorganic pigments, iron oxide pigments are widely used in building materials, coatings, rubber, plastics, paint, etc. In this paper, black iron oxide pigment was used as the carrier, and alumina substance was used as the support. Precipitation method was used to synthesize the aluminum oxide-coated iron oxide black composite pigment under different experimental conditions, and the coated iron was studied by XRD, SEM and TEM characterization methods. The structure of the black pigment, discuss the influence of the coating temperature, reaction pH, coating method, neutralizing acid and other factors on the microstructure of the composite material and the performance of the pigment. The experimental results show that, through co-current coating, the temperature of the reaction system of 80∘C and the reaction pH of 10–11 are the best parameters for coating. The oil absorption, tinting power, hiding power and dispersion power of the coated iron black were tested, and the performance of the iron black pigment was greatly improved after the coating. The heat resistance and light fastness of iron black were tested through the color difference change experiment. The experimental results showed that the heat resistance and light fastness of iron black pigment showed good performance after coating.

scholarly journals Adsorption and Equilibrium Studies on the Removal of Methyl Red from Aqueous Solution Using White Potato Peel Powder

2017 ◽  
Vol 72 ◽  
pp. 52-64 ◽  
Author(s):  
Conrad K. Enenebeaku ◽  
Nnaemeka J. Okorocha ◽  
Uchechi E. Enenebeaku ◽  
Ikechukwu C. Ukaga
Keyword(s):  
Aqueous Solution ◽  
Dye Adsorption ◽  
Freundlich Isotherm ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Methyl Red ◽  
Potato Peel ◽  
White Potato ◽  
Equilibrium Studies

The potential of white potato peel powder for the removal of methyl red (MR) dye from aqueous solution was investigated. The adsorbent was characterized by FTIR and SEM analysis. Batch adsorption studies were conducted and various parameters such as contact time, adsorbent dosage, initial dye concentration, pH and temperature were studied to observe their effects in the dye adsorption process. The optimum conditions for the adsorption of MR onto the adsorbent (WPPP) was found to be contact (80 mins), pH (2) and temperature (303K) for an initial MR dye concentration of 50mg/l and adsorbent dose of 1.0g. The experimental equilibrium adsorption data of the (MR) dye fitted best and well to the Freundlich isotherm model. The maximum adsorption capacity was found to be 30.48mg/g for the adsorption of MR. The kinetic data conforms to the pseudo – second order kinetic model.

scholarly journals Preparation of Chitosan/Hyperbranched Polyester/Cobalt Composite For Acid Blue 277 Dye Adsorption

2020 ◽  
Vol 11 (4) ◽  
pp. 11653-11665
Keyword(s):  
Particle Size ◽  
Dye Adsorption ◽  
Particle Size Analysis ◽  
Isotherm Models ◽  
Size Analysis ◽  
Order Kinetic ◽  
Hyperbranched Polyester ◽  
Acid Dye ◽  
Equilibrium Studies ◽  
Acid Blue

Acid dye effluents are among the popular threatening sources to the environment and human health due to their photochemical stability, complexity, and poor biodegradability. Therefore, this study aims to prepare chitosan/hyperbranched polyester (HBPE)/cobalt composite with ratio (1:1:0.5 wt %, respectively) using emulsion technique as an adsorbent to deal with the acid dye effluent. Chemical structure, morphology, particle size analysis, and thermal stability of the prepared composite were carried out using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM),) dynamic light scattering technique (DLS) and thermogravimetric analysis (TGA). Adsorption isotherms of acid blue 277 dye (AB277), using the different isotherm models (Langmuir, Freundlich, D-R, and Temkin) under removal conditions at pH 3.0 and contact time of 1 h in 10 mL aqueous medium at 25ᴼC, were investigated. The results illustrated that the chitosan/HBPE/Co composite was successfully prepared with a particle size of around 679±494 nm relative to chitosan/HBPE (139±67.6 nm). Also, the pseudo-second-order kinetic model fitted better than the pseudo-first-order one for adsorption of AB277. Batch equilibrium studies showed that chitosan/HBPE/Co composite could be employed as an efficient adsorbent of AB277 dye with an adsorption capacity of 26.74 mg/g, relative to that of chitosan/HBPE (3.19 mg/g).

Research of stamping of unequal channel bars. Part 5. Methods for calculating the extrusion of channels. 2. Extrusion of non-strengthening material

2021 ◽  
pp. 46-52
Author(s):  
A.L. Vorontsov
Keyword(s):  
Plane Strain ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
High Accuracy ◽  
Experimental Results ◽  
Die Forging

The results of experimental studies on the extrusion of channels from non-strengthening material are presented. Comparison of theoretical calculations with experimental results showed the high accuracy of the derived formulas. Keywords: die forging, extrusion, punch, matrix, misalignment, plane strain. [email protected]

Young’s Experiment on Slits with an Angle Between Them

2014 ◽  
Vol 9 (2) ◽  
pp. 173-179
Author(s):  
Anton Bogomyagkov ◽  
Viktor Dorokhov ◽  
Oleg Meshkov ◽  
Aleksandr Polygalov ◽  
Alexey Shcheglov
Keyword(s):  
Experimental Data ◽  
Interference Pattern ◽  
Intensity Distribution ◽  
Mathematical Analysis ◽  
Theoretical Calculations ◽  
Experimental Results ◽  
Digital Data ◽  
Hyperbolic Function ◽  
Standard Laboratory ◽  
Arbitrary Angle

Here are proposed a modified version of Young’s experiment on slits with an arbitrary angle between them. Also here performed mathematical analysis of the proposed scheme, showing that the intensity distribution can be approximated by a hyperbolic function. Experimental data confirm theoretical calculations. Analysis of the experimental results has conducted using two different methods of processing the digital data of the interference pattern. Theoretical calculations and experimental results established a nontrivial fact, that the interference patterns for slits with different, but symmetrical respect to 90° angles have the same intensity distribution. This experiment may be used as a standard laboratory work in University on optics workshop

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