scholarly journals Adsorption Behavior of Crystal Violet and Congo Red Dyes on Heat-Treated Brazilian Palygorskite: Kinetic, Isothermal and Thermodynamic Studies

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5688
Author(s):  
Vanderlane Cavalcanti Silva ◽  
Maria Eduarda Barbosa Araújo ◽  
Alisson Mendes Rodrigues ◽  
Maria do Bom Conselho Vitorino ◽  
Juliana Melo Cartaxo ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Crystal Violet ◽  
Congo Red ◽  
Adsorptive Capacity ◽  
Anionic Dyes ◽  
Isothermal Model ◽  
X Ray ◽  
Heat Treated ◽  
Different Temperatures ◽  
Adsorption Desorption

The effect of heat treatment on the adsorptive capacity of a Brazilian palygorskite to remove the dyes crystal violet (CV) and congo red (CR) was investigated. The natural palygorskite was calcined at different temperatures (300, 500 and 700 °C) for 4 h. Changes in the palygorskite structure were evaluated using X-ray diffraction, X-ray fluorescence, thermogravimetric and differential thermal analysis, N2 adsorption/desorption and Fourier transform infrared spectroscopy. The adsorption efficiency of CV and CR was investigated through the effect of initial concentration, contact time, temperature, pH and dosage of adsorbent. The calcination increased the adsorption capacity of palygorskite, and the greatest adsorption capacity of CV and CR dyes occurred in the sample calcined at 700 °C (Pal-700T). The natural and calcined samples at 300 and 500 °C followed the Freundlich isothermal model, while the Pal-700T followed the Langmuir isothermal model. Adsorption kinetics results were well described by the Elovich model. Pal-700T showed better adsorption performance at basic pH, with removal greater than 98%, for both dyes. Pal-700T proved to be a great candidate for removing cationic and anionic dyes present in water.

scholarly journals Adsorption Behavior of Acid-Treated Brazilian Palygorskite for Cationic and Anionic Dyes Removal from the Water

2021 ◽  
Vol 13 (7) ◽  
pp. 3954
Author(s):  
Vanderlane C. Silva ◽  
Maria Eduarda B. Araújo ◽  
Alisson M. Rodrigues ◽  
Juliana M. Cartaxo ◽  
Romualdo R. Menezes ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Raw Material ◽  
Adsorption Behavior ◽  
Isotherm Model ◽  
Adsorptive Capacity ◽  
Anionic Dyes ◽  
Adsorption Parameters ◽  
X Ray ◽  
Adsorption Desorption

The effect of acid treatment on the adsorptive capacity of a Brazilian palygorskite to remove the crystal violet (CV) and congo red (CR) dyes was investigated. The raw palygorskite was acid-treated by different HCl solutions (2, 4, and 6 mol/L). The modifications on the palygorskite structure were investigated using X-ray diffraction, X-ray fluorescence, Fourier-transform infrared spectroscopy, N2 adsorption/desorption, and thermogravimetric and differential thermal analysis. The efficiency of CV and CR adsorption was investigated, and the effect of the initial concentration, contact time, pH, and adsorbent amount was analyzed. The results revealed that CV adsorption in the acid-treated palygorskite was higher than that of the raw material. A Langmuir isotherm model was observed for the adsorption behavior of CV, while a Freundlich isotherm model was verified for the CR adsorption. A pseudo-second-order model was observed for the adsorption kinetics of both dyes. The higher CV adsorption capacity was observed at basic pH, higher than 97%, and the higher CR removal was observed at acidic pH, higher than 50%. The adsorption parameters of enthalpy (ΔH), entropy (ΔS), and Gibbs energy (ΔG) were evaluated. The adsorption process of the CV and CR dyes on the raw and acid-treated Brazilian palygorskite was predominantly endothermic and occurred spontaneously. The studied raw palygorskite has a mild-adsorption capacity to remove anionic dyes, while acid-treated samples effectively remove cationic dyes.

Mg(OH)2/Graphene Nanocomposites Prepared by Cathodic Electrodeposition for the Adsorption of Congo Red

NANO ◽  
2017 ◽  
Vol 12 (02) ◽  
pp. 1750017 ◽  
Author(s):  
Xinzhong Deng ◽  
Yaowu Wang ◽  
Jianping Peng ◽  
Kejia Liu ◽  
Naixiang Feng ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Congo Red ◽  
Anionic Dyes ◽  
Graphene Nanocomposites ◽  
X Ray ◽  
Cathodic Electrodeposition ◽  
Transmission Electron ◽  
Pseudo Second Order ◽  
Energy Formula

A facile cathodic electrodeposition process was developed to prepare Mg(OH)2/Graphene nanocomposites (MGN), which was used to remove Congo Red (CR), an anionic dye from aqueous solution. The morphology and phase structure were analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman and X-ray photoelectron spectroscopy (XPS). The effects of experimental parameters, such as graphene content, adsorption time, initial concentrations of CR and pH values, on the adsorption capacity of CR were studied. The obtained MGN shows the good performance in CR, with an adsorption capacity of 1986.43[Formula: see text]mg[Formula: see text]g[Formula: see text]. The equilibrium adsorption and kinetics data fit with Langmuir isotherm and the pseudo-second-order model, respectively. Thermodynamic data suggest that CR adsorption onto MGN is spontaneous ([Formula: see text]: –9.62[Formula: see text]kJ[Formula: see text]mol[Formula: see text] at 313[Formula: see text]K, endothermic ([Formula: see text]: 36.261[Formula: see text]kJ[Formula: see text]mol[Formula: see text] and the degree of disorder increased ([Formula: see text]: 146.848[Formula: see text]J[Formula: see text]moL[Formula: see text][Formula: see text]K[Formula: see text] at the solid-solution interface. Moreover, the adsorption activation energy ([Formula: see text]: 38.929[Formula: see text]kJ[Formula: see text]mol[Formula: see text] of CR evaluated from the Arrhenius equation illustrates that it is a physical process. This adsorbent exhibits efficient adsorption properties and high recycling efficiency, making it a promising adsorbent for removing anionic dyes.

Synthesis and Characterization of an Experimental Zn-Hydroxyapatite Powders with Application in Dentistry

2013 ◽  
Vol 587 ◽  
pp. 43-51 ◽  
Author(s):  
Doina Prodan ◽  
Marioara Moldovan ◽  
Cristina Prejmerean ◽  
Laura Silaghi-Dumitrescu ◽  
Stanca Boboia ◽  
...  
Keyword(s):  
Size Distribution ◽  
Nanometer Scale ◽  
Size Distributions ◽  
Sem Images ◽  
X Ray ◽  
Microstructural Parameters ◽  
Heat Treated ◽  
Different Temperatures ◽  
Adsorption Desorption

In the present study, Zn-hydroxyapatite (Zn-HA) was synthesized, the powder was thermally treated at different temperatures and then characterized. The Zn-HA powder was characterized mainly by FTIR and XRD, but have been performed investigations like SEM, BET and size distribution. The addition of ZnO in hydroxyapatite causes alleged interactions with the existing groups in HA, which amend the corresponding signals to these groups in the IR spectra. X-ray diffractograms for samples (untreated and heat-treated) have been recorded and microstructural parameters for the all samples have been calculated. The obtained average sizes of the crystallites and the network tensions support the idea that Zn-HA powders are nanostructured. The SEM images and size distributions for Zn-HA indicate a cluster of crystals with nanometer-scale of the population-base. Was determined the adsorption-desorption isotherms for Zn-HA powder at 100 o C and 800 o C. The dates obtained from the analysis of particle size distribution indicates for the Zn-HA powder an size distribution for granules in the range from 0.05 to 0.3μm

scholarly journals Sulphate-Crosslinked Chitosan as an Adsorbent for the Removal of Congo Red Dye From Aqueous Solution

2018 ◽  
Vol 11 ◽  
pp. 117862211881168 ◽  
Author(s):  
Christine Jeyaseelan ◽  
Nisha Chaudhary ◽  
Ravin Jugade
Keyword(s):  
Adsorption Capacity ◽  
Congo Red ◽  
Water Bodies ◽  
X Ray ◽  
Modified Chitosan ◽  
Freundlich Adsorption Isotherm ◽  
Pseudo Second Order ◽  
Crosslinked Chitosan ◽  
Wastewater Samples ◽  
Red Dye

Dyes are a major cause of concern nowadays as large quantities are being released into water bodies causing pollution. In this article, modified chitosan (sulphate crosslinked) has been studied for the removal of Congo red (a benzidine-based anionic diazo dye) which is a toxic dye introduced into water bodies from textile industries. Sulphate-crosslinked chitosan (SCC) was prepared in the laboratory and the characterization of SCC was done by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Various parameters such as pH, contact time, adsorbent dosage, and concentration of adsorbent were optimized. The adsorption capacity was determined at pH 3.0, at which the percentage recovery was about 90% and followed Freundlich adsorption isotherm with an adsorption capacity of 91.8 mg/g. The adsorption followed pseudo-second-order kinetics. Various thermodynamic parameters were also determined for the change in adsorption with temperature. The SCC was regenerated with NaOH and showed good recycling capacity. The modified chitosan was applied for the removal of Congo red from industrial wastewater samples (spiked).

scholarly journals Environmentally Friendly Mesoporous Nanocomposite Prepared from Al-Dross Waste with Remarkable Adsorption Ability for Toxic Anionic Dye

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Inas A. Ahmed ◽  
Najlaa S. Al-Radadi ◽  
H. S. Hussein ◽  
Ahmed H. Ragab
Keyword(s):  
Crystal Size ◽  
Pore Radius ◽  
Morphological Properties ◽  
Anionic Dyes ◽  
Adsorption Ability ◽  
Waste Products ◽  
X Ray ◽  
Anionic Dye ◽  
Eriochrome Black T ◽  
Adsorption Desorption

In this work, a mesoporous nanocomposite composed of nanogibbsite (α-Al(OH)3) and nanosilica was prepared. Gibbsite nanoparticles (GNPs) with a crystal size of ≈38 nm were prepared from Al-dross industrial waste products in an acidic environment at 100°C. Nanosilica (NS) with a crystal size of ≈13 nm was prepared from sodium silicate using dilute hydrochloric acid. The deposition of nanosilica onto gibbsite particles was investigated. The mesoporous silica-gibbsite (NSG) nanocomposite was examined by evaluating its ability to adsorb the toxic anionic dye Eriochrome black T (EBT) from aqueous solution. The compositional and morphological properties of NSG nanocomposites were studied by means of the FTIR spectroscopy, X-ray fluorescence (XRF), XRD, SEM, and TEM techniques. The effect of dye concentration, pH, adsorbent dose, contact time, and temperature was investigated. The sorption models, the isotherms, and the thermodynamic parameters ΔHo, ΔGo, and ΔSo were evaluated. The N2 adsorption-desorption isotherms revealed that mixing the two prepared materials (NS and GNPs) to form the NSG nanocomposite resulted in good properties (a surface area of 62.34 m2·g−1, a pore radius of 22.717 nm, and a pore volume of 0.7081 cm3·g−1). The results show that the prepared NSG nanocomposite has a remarkable ability to adsorb toxic anionic dyes.

Adsorption of Crystal Violet oNto Nitrogen-Doped Mesoporous Carbon

2017 ◽  
Vol 42 (3) ◽  
pp. 269-281
Author(s):  
Lvling Zhong ◽  
Liang Zhang ◽  
Hongliang Shi
Keyword(s):  
Adsorption Capacity ◽  
Crystal Violet ◽  
Photoelectron Spectroscopy ◽  
Control Process ◽  
Maximum Adsorption Capacity ◽  
Nitrogen Doped ◽  
First Order Kinetics ◽  
Equilibrium Data ◽  
Langmuir Isotherm Model ◽  
Adsorption Desorption

A series of nitrogen-doped mesoporous carbons (NDMCs) was prepared using p-phenylenediamine and glyoxal as a carbon source and mesoporous silica as a hard template. N2 adsorption–desorption isotherms indicated that mesopores with a wider distribution exist in NDMCs. Elemental analysis showed that the N content on the surface of NDMC-800 was 9.9at.%, with a result close to 8.4at.% from X-ray photoelectron spectroscopy. The adsorption capacity of NDMCs for crystal violet (CV) in aqueous solution was investigated. Static equilibrium data were well described by the Langmuir isotherm model, with a maximum adsorption capacity of 243.9 mg g−1. Adsorption kinetics data suggested that the adsorption control process follows the pseudo first-order kinetics model. The results showed that this carbon material has the potential for application in adsorption of CV.

scholarly journals Preparation of GO/MIL-101(Fe,Cu) composite and its adsorption mechanisms for phosphate in aqueous solution

2021 ◽  
Author(s):  
You Wu ◽  
Zuannian Liu ◽  
Bakhtari Mohammad Fahim ◽  
Junnan Luo
Keyword(s):  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Adsorption Mechanism ◽  
Nitrogen Adsorption ◽  
Adsorption Properties ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Adsorption Mechanisms ◽  
Adsorption Desorption

Abstract In this study, MIL-101(Fe), MIL-101(Fe,Cu), and Graphene Oxide (GO) /MIL-101(Fe,Cu) were synthesized to compose a novel sorbent. The adsorption properties of these three MOFs-based composites were compared toward the removal of phosphate. Furthermore, the influencing factors including reaction time, pH, temperature and initial concentration on the adsorption capacity of phosphate on these materials as well as the reusability of the material were discussed. The structure of fabricated materials and the removal mechanism of phosphate on the composite material were analyzed by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption analysis and zeta potential. The results show that the maximum adsorption capacity of phosphate by the composite GO/MIL-101(Fe,Cu)-2% was 204.60 mg·g− 1, which is higher than that of MIL-101(Fe,Cu) and MIL-101(Fe). likewise the specific surface area of GO/MIL-101(Fe,Cu)-2% is 778.11 m2/g is higher than that of MIL-101(Fe,Cu) and MIL-101(Fe),which are 747.75 and 510.66m2/g respectively. The adsorption mechanism of phosphate is electrostatic attraction, form coordination bonds and hydrogen bonds. The fabricated material is a promising adsorbent for the removal of phosphate with good reusability.

scholarly journals Understanding the physicochemical properties of Zn–Fe LDH nanostructure as sorbent material for removing of anionic and cationic dyes mixture

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rehab K. Mahmoud ◽  
Mohamed Taha ◽  
Amal Zaher ◽  
Rafat M. Amin
Keyword(s):  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Adsorption Process ◽  
Dye Adsorption ◽  
Chemical Properties ◽  
Cationic Dyes ◽  
Anionic Dyes ◽  
Visible Radiation ◽  
X Ray ◽  
Before And After

AbstractIn our work, the removal of cationic and anionic dyes from water was estimated both experimentally and computationally. We check the selectivity of the adsorbent, Zn–Fe layered double hydroxide (LDH) toward three dyes. The physical and chemical properties of the synthesis adsorbent before and after the adsorption process were investigated using X-ray photoelectron spectroscopy, energy dispersive X-ray, X-ray diffraction, FT-IR, HRTEM, and FESEM analysis, particle size, zeta potential, optical and electric properties were estimated. The effect of pH on the adsorption process was estimated. The chemical stability was investigated at pH 4. Monte Carlo simulations were achieved to understand the mechanism of the adsorption process and calculate the adsorption energies. Single dye adsorption tests revealed that Zn–Fe LDH effectively takes up anionic methyl orange (MO) more than the cationic dyes methylene blue (MB) and malachite green (MG). From MO/MB/MG mixture experiments, LDH selectively adsorbed in the following order: MO > MB > MG. The adsorption capacity of a single dye solution was 230.68, 133.29, and 57.34 mg/g for MO, MB, and MG, respectively; for the ternary solution, the adsorption capacity was 217.97, 93.122, and 49.57 mg/g for MO, MB, and MG, respectively. Zn–Fe LDH was also used as a photocatalyst, giving 92.2% and 84.7% degradation at concentrations of 10 and 20 mg/L, respectively. For visible radiation, the Zn–Fe LDH showed no activity.

scholarly journals Enhanced Photocatalytic Activity of TiO2/SnO2 Binary Nanocomposites

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Tetiana A. Dontsova ◽  
Anastasiya S. Kutuzova ◽  
Kateryna O. Bila ◽  
Svitlana O. Kyrii ◽  
Iryna V. Kosogina ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Synthesis ◽  
Low Temperature ◽  
Hydrothermal Method ◽  
Oxide Content ◽  
Porous Structures ◽  
Anionic Dyes ◽  
Commercial Sample ◽  
X Ray ◽  
Adsorption Desorption

The paper presents the results of characterization and study of adsorption-photocatalytic properties of commercial and synthesized-by-hydrothermal method TiO2 and TiO2-SnO2 nanocomposites. Hydrothermal synthesis of TiO2-based nanocomposites was performed in two ways: single-stage and two-stage methods. Characterization was carried out by XRD, X-ray fluorescence method, XPS, EPR, PL, and low-temperature adsorption-desorption of nitrogen, which showed that TiO2-SnO2 nanostructured composites were obtained with tin(IV) oxide content of 10 wt.% and had acidic surface and different porous structures. Besides, modification of a commercial sample with tin(IV) oxide led to a slight decrease in the specific surface area, while modification of a synthesized-by-hydrothermal method TiO2 sample led to an increase. It was found that sorption properties of the obtained nanocomposites and pure TiO2 are better towards anionic dyes. Photocatalytic activity, on the contrary, is higher towards cationic dyes, which is consistent with additional studies on the destruction of these dyes. It was established that in terms of photocatalytic activity, TiO2-SnO2 nanocomposites are more promising than solid solutions, and modification of TiO2 with tin(IV) oxide, in general, leads to improvement of its photocatalytic activity.

Biosorption of crystal violet dye using inactive biomass of the fungus Diaporthe schini

2019 ◽  
Vol 79 (4) ◽  
pp. 709-717 ◽  
Author(s):  
Patrícia Grassi ◽  
Caroline Reis ◽  
Fernanda C. Drumm ◽  
Jordana Georgin ◽  
Denise Tonato ◽  
...  
Keyword(s):  
Crystal Violet ◽  
X Ray Diffraction ◽  
N2 Adsorption ◽  
Biosorption Capacity ◽  
X Ray ◽  
Crystal Violet Dye ◽  
Endothermic Process ◽  
Desorption Isotherms ◽  
Adsorption Desorption ◽  
Scanning Electron

Abstract An inactive biomass of a new fungus recently discovered, Diaporthe schini, was evaluated for the biosorption of crystal violet (CV) in simulated textile effluents. The characterization assays were performed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms. The influences of pH and biosorbent dosage on the biosorption capacity were evaluated. Kinetics, equilibrium and thermodynamic studies were also carried out. Characterization techniques showed an amorphous biosorbent, with a rough surface containing irregular particles and surface area of 6.5 m2 g−1. The most adequate values of pH and biosorbent dosage were 7.5 and 0.4 g L−1, respectively. The Elovich kinetic model and the Sips equilibrium model were suitable to fit the experimental data. The biosorption capacity increased with temperature, reaching a maximum biosorption capacity of 642.3 mg g−1 at 328 K. The biosorption was a spontaneous and endothermic process. Diaporthe schini inactive biomass was an interesting biosorbent to treat colored effluents, presenting efficiency of 87% in the decolorization of a simulated dye house effluent.

Sign in / Sign up

Export Citation Format

Share Document