scholarly journals Preparation of Functionalized Hydroxyapatite with Biopolymers as Efficient Adsorbents of Methylene Blue

2021 ◽  
Author(s):  
Hassen Agougui ◽  
Youssef Guesmi ◽  
Mahjoub Jabli
Keyword(s):  
Methylene Blue ◽  
Sodium Alginate ◽  
Cationic Dye ◽  
X Ray Diffraction ◽  
Trans Form ◽  
Fourier Trans ◽  
Pseudo Second Order ◽  
Adsorbed Quantity ◽  
Potential Use ◽  
Scanning Electron

In this study, we reported the synthesis of hydroxyapatite modified with biopolymers as λ-carrageenan and sodium alginate, which could be used as effective adsorbents of cationic dyes. Evidence of chemical modification was proved through chemical analysis, Fourier Trans-form Infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, and specific surface area. The adsorption process was studied using methylene blue as representative cationic dye. The adsorbed quantity reached, at equilibrium, 142.85 mg/g and 98.23 mg/g using hydroxyapatite-sodium alginate and hydroxyapatite-(λ-carrageenan), respectively. However, it does not exceed 58.8 mg/g in the case of the unmodified hydroxyapatite. The adsorption of methylene blue using hybrid materials complied well with the pseudo-second-order suggesting a chemi-sorption. Freundlich and Langmuir isotherm described well the adsorption mechanism of the hydroxyapatite-(λ-carrageenan) and hydroxyapatite-sodium alginate, respectively. The high capacities of MB removal obtained in this study suggest the potential use of these materials in the treatment from wastewaters.

scholarly journals Study of Methylene Blue Adsorption by Modified Kaolinite by Dimethyl Sulfoxide

2020 ◽  
Vol 27 (2) ◽  
pp. 225-239
Author(s):  
Salima Lellou ◽  
Samir Kadi ◽  
Laid Guemou ◽  
Jacques Schott ◽  
Hadj Benhebal
Keyword(s):  
Methylene Blue ◽  
Dimethyl Sulfoxide ◽  
Kinetic Data ◽  
Contact Time ◽  
Basal Spacing ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pseudo Second Order ◽  
Scanning Electron ◽  
Good Agreement

AbstractTamazert kaolin was modified with dimethyl sulfoxide (DMSO). The starting material and resulting from the intercalation were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Intercalation caused considerable changes in our clay by increasing the basal spacing to 11.22 Å, an intercalation rate of 98 %. The adsorption of methylene blue was studied as a function of pH, contact time, temperature, dye concentrations and adsorbents. Kinetic data have been adequately described by the pseudo-second order and intraparticle scattering model. The adsorption isotherm is in good agreement with the Redlich-Peterson model. A change in thermodynamic values (ΔH°, ΔS° and ΔG°) was observed after intercalation. Adsorption became non-spontaneous exothermic and ordered.

Synthesis of Visible-Light Responsive CdS/ZnO Nanocomposite Photocatalysts via Simple Precipitation Method

2014 ◽  
Vol 608 ◽  
pp. 224-229 ◽  
Author(s):  
Potjanaporn Chaengchawi ◽  
Karn Serivalsatit ◽  
Pornapa Sujaridworakun
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Performance ◽  
Precipitation Method ◽  
Cds Nanoparticles ◽  
Methylene Blue Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Blue Solution ◽  
Scanning Electron

A visible-light responsive CdS/ZnO nanocomposite photocatalyst was successfully synthesized by precipitation of CdS nanoparticles, using Cd (NO3)2 and Na2S as starting materials, on ZnO nanoparticles and then calcined at 400°C for 2 hours. The effects of the mole ratio of CdS and ZnO in the composites on their phase, morphology, and surface area were investigated by X-ray Diffraction (XRD), scanning electron microscope (SEM), Brunauer Emmett Teller method (BET), respectively. The photocatalytic degradation of methylene blue solution in the presence of composite products under visible-light irradiation was investigated. The results showed that the mole ratio of CdS and ZnO played a significant role on photocatalytic performance. The highest photocatalytic activity was obtained from the CdS/ZnO nanocomposite with mole ratio of 1:4, which is higher than that of pure CdS and pure ZnO.

scholarly journals Natural and Modified Clays for the Removal of Cationic Dye from Water

2020 ◽  
Vol 24 (1) ◽  
pp. 562-579
Author(s):  
Asma Behilil ◽  
Driss Lancene ◽  
Brahim Zahraoui ◽  
Meriem Belhachemi ◽  
Houcine Benmehdi ◽  
...  
Keyword(s):  
Low Cost ◽  
Scientific Work ◽  
Exchange Capacity ◽  
Cationic Dye ◽  
X Ray Diffraction ◽  
Treatment Processes ◽  
Bet Analysis ◽  
Cost Treatment ◽  
Pseudo Second Order ◽  
Bet Theory

Abstract Research and scientific work continue to develop low-cost treatment processes in terms of improving water quality and environmental protection. Oxide of zinc supported in natural clay is synthesized by impregnated method. The role of this modification is to increase the adsorption capacity of a basic dye (Methylene Blue) compared with calcined and natural clays. These samples are characterized by several analytical methods, X-Ray Diffraction (XRD), Thermogravimetric Analysis/Differential Thermal Analysis (TGA/TDA) and Brunauer, Emmett and Teller (BET) theory. The results show that these clays contain three phases, Sericite 2M1, Clinochlore, quartz and the presence of a new phase for the modified clay named zincite. The measured cation exchange capacity (CEC) is 9 cmolc/kg and the BET analysis shows the increase of surface area for these clays, from 9 to 30 m2 g−1. The findings show also that the impregnated clay has a better affinity than others when the kinetics data were well fitted by the pseudo-second-order. The adsorption capacities calculated using Langmuir equation of MB onto natural, calcined and impregnated clays are 154.0, 139.6 and 158.1 mg/g, respectively. The thermodynamic data showed that the adsorption of MB on these samples were exothermic. From this study, it can be concluded that these clays are efficacious materials for cationic dye removal from wastewater.

Elimination of Acid Red 88 by Waste Product from the Phosphate Industry: Batch Design and Regeneration

2021 ◽  
Author(s):  
Khaled Boughzala ◽  
Mustapha Hidouri
Keyword(s):  
Electron Microscopy ◽  
Experimental Data ◽  
Thermal Analysis ◽  
Waste Product ◽  
Langmuir Model ◽  
X Ray Diffraction ◽  
Retention Capacity ◽  
Phosphate Industry ◽  
Pseudo Second Order ◽  
Scanning Electron

Waste regenerated after washing of rock phosphate and phosphogypsum has been proposed as removal agents of Acid Red 88 (AR 88)) from artificially contaminated solution. Natural phosphate (PN) was also studied for comparison. These materials were characterized beforehand, as is intended for the removal tests, by chemical analysis, powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis– differential thermal analysis, scanning electron microscopy, and N2 adsorption isotherms. The conducted experiments show that among the different materials, the PWR has the highest retention capacity of the dye (123.4 mg g−1) of AR-88. Upon calcinations, the removal capacities reduced by 60 to 70%. We take note also that a decrease in the amount of removed AR 88 dye occurs with an increase in pH. The kinetics data on the reaction between AR 88 and the materials are described well by a pseudo -second-order model. The Langmuir model is successfully applied to the experimental data of the removal of acid red 88. The removal process is exothermic.

Thermo-Kinetic Study of Adsorption of Methylene Blue in Aqueous Solutions Using Algerian Illite Natural and Activated Mineral Clay

2021 ◽  
Vol 406 ◽  
pp. 348-363
Author(s):  
Larbi Haddad ◽  
Abdelkader Hima ◽  
Belkhir Dadamoussa ◽  
Asma Messai Aoun
Keyword(s):  
Methylene Blue ◽  
Specific Area ◽  
Experimental Results ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Isotherm Equation ◽  
Langmuir Isotherm Equation ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Two Stages

In this study, a local mineral clay was used as an adsorbent for the elimination of a cationic dye: methylene blue (MB), in an aqueous solution by adsorption technique. Early on, we performed mineralogical and textural analyses of a clay sample using various techniques, namely X-ray diffraction, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. The experimental results showed that this adsorbent is a mesoporous and non-swelling clay with illite and kaolinite as the major components with a specific area of about 110m2/g. The study of MB adsorption on the clay was carried out by optimizing the conditions of adsorption, notably the initial concentration of pollutant C0, the mass of clay m, the contact time t, the potential of hydrogen of the solution pH and the temperature T. Experimental results have shown that the equilibrium data are well adjusted by a Langmuir isotherm equation. Thermodynamic parameters such as the changes in Gibbs free energy, enthalpy, and entropy were determined from batch experiments. Results revealed that the adsorption of MB onto illitic clay was endothermic and spontaneous process. Kinetic modeling was also carried out. Experimental data adjusted the kinetic model of pseudo-second order with two stages of intraparticle diffusion.

scholarly journals The Adsorption of Methylene Blue on Eco-Friendly Reduced Graphene Oxide

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 681 ◽  
Author(s):  
Fabian Arias Arias ◽  
Marco Guevara ◽  
Talia Tene ◽  
Paola Angamarca ◽  
Raul Molina ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Maximum Adsorption Capacity ◽  
Green Protocol ◽  
Reduced Graphene ◽  
Wastewater Systems ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Potential Use

Recently, green-prepared oxidized graphenes have attracted huge interest in water purification and wastewater treatment. Herein, reduced graphene oxide (rGO) was prepared by a scalable and eco-friendly method, and its potential use for the removal of methylene blue (MB) from water systems, was explored. The present work includes the green protocol to produce rGO and respective spectroscopical and morphological characterizations, as well as several kinetics, isotherms, and thermodynamic analyses to successfully demonstrate the adsorption of MB. The pseudo-second-order model was appropriated to describe the adsorption kinetics of MB onto rGO, suggesting an equilibrium time of 30 min. Otherwise, the Langmuir model was more suitable to describe the adsorption isotherms, indicating a maximum adsorption capacity of 121.95 mg g−1 at 298 K. In addition, kinetics and thermodynamic analyses demonstrated that the adsorption of MB onto rGO can be treated as a mixed physisorption–chemisorption process described by H-bonding, electrostatic, and π − π interactions. These results show the potential of green-prepared rGO to remove cationic dyes from wastewater systems.

scholarly journals Borax-Cross-Linked Guar Gum-Manganese Dioxide Composites for Oxidative Decolorization of Methylene Blue

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Rohan S. Dassanayake ◽  
Erandathi Rajakaruna ◽  
Noureddine Abidi
Keyword(s):  
Electron Microscopy ◽  
Methylene Blue ◽  
Manganese Dioxide ◽  
Guar Gum ◽  
Spectrophotometric Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Decolorization Efficiency ◽  
Desorption Mechanism ◽  
Scanning Electron

Borax-cross-linked guar gum-manganese dioxide (GGB-MnO2) composite was synthesized using an environmentally friendly synthesis route and investigated for its efficiency of decolorizing methylene blue (MB) dye solution by an ultraviolet-visible (UV-Vis) spectrophotometric study. The GGB-MnO2 composite was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). The composite (1.2 g/L) exhibited excellent oxidative decolorization of MB (30 mg/L, 50 mL) solution to over 99% in 6, 13, and 40 min at pH 4, 7, and 10, respectively. The complete decolorization of MB occurred via a catalytic adsorption-oxidation-desorption mechanism. The GGB-MnO2 composite showed very good reusability and was stable after ten successive cycles with negligible losses of the decolorization efficiency.

Characterization of LSCF-Based Composite and LSCF as Cathodes for Intermediate Temperature SOFCs

2012 ◽  
Vol 727-728 ◽  
pp. 657-662
Author(s):  
Reinaldo Azevedo Vargas ◽  
Everton Bonturim ◽  
Marco Andreoli ◽  
Rubens Chiba ◽  
Emília Satoshi Miyamaru Seo
Keyword(s):  
Solid Oxide Fuel Cells ◽  
Solid Oxide ◽  
Intermediate Temperature ◽  
Oxide Fuel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Spraying ◽  
Potential Use ◽  
Scanning Electron

The (La0.60Sr0.40)(Co0.20Fe0.80)O3-δ - LSCF, (Ce0.90Gd0.10)O1.95 - CGO composites and LSCF were deposited by wet powder spraying deposition method for the purpose of investigating their potential use in Intermediate Temperature Solid Oxide Fuel Cells. The interlayers are necessary between CGO electrolytes and LSCF cathodes in order to improve the performance of these materials. LSCF particles synthesized by citrate technique were calcined at 900 °C for 4 h and, their LSCF-CGO composites and LSCF suspensions deposited on CGO substrate and, sintered in 1100 °C for 1 h, were formed pseudo-perovskite. The ceramics materials were analyzed by X-ray diffraction (XRD) and chemical composition of different half-cells layers by scanning electron microscope with energy dispersive (SEM-EDS). The results are in agreement with the literature and indicate that route studied is adequate for crystal structures formation compatible with films the 35 µm thick total for study of conductivity between the cathode and the electrolyte.

scholarly journals Preparation of BaZrO3 powders by a spray-drying process

2003 ◽  
Vol 18 (6) ◽  
pp. 1325-1332 ◽  
Author(s):  
B. Robertz ◽  
F. Boschini ◽  
A. Rulmont ◽  
R. Cloots ◽  
I. Vandriessche ◽  
...  
Keyword(s):  
Spray Drying ◽  
Precursor Solution ◽  
Barium Zirconate ◽  
Drying Process ◽  
X Ray Diffraction ◽  
High Quality ◽  
Corrosion Resistant ◽  
X Ray ◽  
Potential Use ◽  
Scanning Electron

The potential use of barium zirconate for the manufacture of corrosion-resistant substrates emphasizes the need for a simple, inexpensive, and easily scalable process to produce high-quality powders with well-controlled composition and properties. However, the classical solid-state preparation of barium zirconate leads to an inhomogeneous powder unsuitable for applications in highly corrosive environment. For this paper, the possibility to use the spray-drying technique for the preparation of BaZrO3 powders with a controlled size distribution and morphology was investigated. The influence of the nature and concentration of the precursor solution and the influence of the spray-drying step are discussed on the basis of x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and dilatometric measurements.

scholarly journals Potential Use of Green Synthesized Al2O3 (Alumina) Nanoparticles from Guava Leaves (Psidium guajava) for the Removal of Methylene Blue from Wastewater

2021 ◽  
Vol 33 (6) ◽  
pp. 1304-1308
Author(s):  
Debasish Mondal ◽  
Dipankar Mahata ◽  
Kamala Mandy Hansda ◽  
Sourav Mondal ◽  
Ajit Das
Keyword(s):  
Methylene Blue ◽  
Low Cost ◽  
Xrd Analysis ◽  
Psidium Guajava ◽  
Alumina Nanoparticles ◽  
X Ray Diffraction ◽  
Guava Leaves ◽  
Al2o3 Nps ◽  
Potential Use ◽  
Significant Attention

Recently non-harmful nanomaterials have acquired critical significant attention in wastewater treatment containing organic pollutants especially toxic and hazardous dyes. In this regard, a low cost and eco friendly method has been investigated for the green synthesis of alumina nanoparticles (Al2O3 NPs). The alumina nanoparticles were synthesized using an aqueous extract of Psidium guajava leaf as a potential stabilizing agent. The UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) techniques were used to characterize the synthesized nanoparticles. The absorption at 281 nm confirmed the formation of alumina nanoparticles. The FTIR spectra and XRD analysis confirmed the presence of various functional groups and crystalline structures of Al2O3 NPs during the synthesis. The spectrum clearly indicates the organic moieties in Psidium guajava extract are responsible for the biosynthesis of Al2O3 NPs. The suface morphology of Al2O3 NPs was confirmed by SEM and EDS studies. Besides this, the removal of methylene blue through adsorption and kinetic study was also reported.

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