scholarly journals La-Doped ZnTiO3/TiO2 Nanocomposite Supported on Ecuadorian Diatomaceous Earth as a Highly Efficient Photocatalyst Driven by Solar Light

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6232
Author(s):  
Ximena Jaramillo-Fierro ◽  
Silvia González ◽  
Francesc Medina
Keyword(s):  
Diatomaceous Earth ◽  
Diffuse Reflectance Spectroscopy ◽  
Solar Irradiation ◽  
Batch Reactors ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
La Doped

Currently, there is great interest in the use of TiO2 for photocatalytic remediation of wastewater. Doping, heterojunction, and immobilization on porous materials are effective methods to improve the photocatalytic efficiency of this semiconductor oxide. In this study, ZnTiO3/TiO2 (ZTO) and ZnTiO3/TiO2/La (ZTO/La) nanocomposites were successfully prepared and immobilized on diatomaceous earth (DE). The composition and texture of the composites prepared were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM-EDX), and specific surface area (SSA). The adsorption capacity and photocatalytic activity of the composites were determined via degradation of methylene blue (MB) in batch reactors. The materials evaluated were prepared in the shape of 0.2 cm (diameter) and 1.0 cm (length) cylindrical extrudates. The results indicate that the ZTO/La-DE composite exhibited higher efficiency for the removal of MB under solar irradiation than both ZTO-DE and DE. The pseudo-second-order model and the Langmuir isotherm model were better suited to explain the adsorption process. The highest degradation percentage of MB obtained was 96% after 150 min of irradiation. The results indicate that synthesized composite could be used for the removal of cationic dyes in wastewater.

scholarly journals Structuring of ZnTiO3/TiO2 Adsorbents for the Removal of Methylene Blue, Using Zeolite Precursor Clays as Natural Additives

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 898
Author(s):  
Ximena Jaramillo-Fierro ◽  
Silvia González ◽  
Fernando Montesdeoca-Mendoza ◽  
Francesc Medina
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Sol Gel ◽  
Area Measurement ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Surface Area Measurement ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order

Adsorption is an effective method of removing harmful pollutants from air and water. In the present study, zeolites prepared by sol-gel method from two Ecuadorian clays were combined with precursor clays and the ZnTiO3/TiO2 semiconductor for adsorbing methylene blue (MB) as a water contaminant. The synthesized compounds were characterized using powder X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive X-ray, and surface area measurement. These compounds were combined to form cylindrical extrudates of 0.2 cm (diameter) and 1.0 cm (length). The adsorption characteristics of the composites were measured using batch sorption studies as a function of pH, initial concentration, and contact time. The pseudo-second-order model and the Langmuir isotherm model were better suited to the adsorption process. The equilibrium state was achieved around 180 min of adsorption, and a pH of 7 was established as the optimal operating condition. The maximum adsorption values of the dye were obtained with the composites derived from G-Clay, whose average adsorption capacity was 46.36 mg g−1, in contrast with composites derived from R-Clay, whose average adsorption value was 36.24 mg g−1. The results reflect that synthesized composites could be used potentially for the removal of cationic dye from wastewater.

scholarly journals Synthesis, characterization, and evaluation of ZrSiO4/Fe2O3 adsorbent for methylene blue removal in aqueous solutions

2021 ◽  
Vol 882 (1) ◽  
pp. 012019
Author(s):  
T Yuliana ◽  
N Nurlitasari ◽  
A Hardian ◽  
S Budiman ◽  
Jasmansyah ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Order Model ◽  
Textile Waste ◽  
X Ray ◽  
Isotherm Adsorption ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Zircon Sand

Abstract Methylene blue dyes are widely used in textile, batik, plastic, paper, and many other industries. The remain of methylene blue dyes in the textile waste is hazardous for health and the environment. Therefore, it takes effort to deal with it. One of the efforts is the process of adsorption using adsorbents. In this study, the adsorbent ZrSiO4/Fe2O3 was synthesized using the coprecipitation method using NaOH as precipitant. Either ZrSiO4 or Fe2O3 was synthesized from Indonesia mineral local zircon sand and jarosites, respectively. The composites of ZrSiO4/Fe2O3 were prepared in %mole variation, which is 75:25; 50:50; and 25:75. All obtained composites were then characterized using X-Ray Diffraction (XRD). The XRD analysis showed that the crystal structure formed was tetragonal for ZrSiO4 and hexagonal for Fe2O3 (also known as α-Fe2O3). Evaluation toward isotherm adsorption and kinetic adsorption showed that the adsorption of MB using ZrSiO4/Fe2O3 follows the Langmuir isotherm model and pseudo-second-order model, respectively.

scholarly journals Adsorption of strontium on different sodium-enriched bentonites

2017 ◽  
Vol 82 (4) ◽  
pp. 449-463 ◽  
Author(s):  
Sanja Marinovic ◽  
Marija Ajdukovic ◽  
Natasa Jovic-Jovicic ◽  
Tihana Mudrinic ◽  
Bojana Nedic-Vasiljevic ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Adsorption Capacity ◽  
Textural Properties ◽  
X Ray Diffraction ◽  
Order Model ◽  
Surface Areas ◽  
Alkaline Conditions ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Ph Range

Bentonites from three different deposits (Wyoming, TX, USA and Bogovina, Serbia) with similar cation exchange capacities were sodium enriched and tested as adsorbents for Sr2+ in aqueous solutions. X-Ray diffraction analysis confirmed successful Na-exchange. The textural properties of the bentonite samples were determined using low-temperature the nitrogen physisorption method. Significant differences in the textural properties between the different sodium enriched bentonites were found. Adsorption was investigated with respect to adsorbent dosage, pH, contact time and the initial concentration of Sr2+. The adsorption capacity increased with pH. In the pH range from 4.0?8.5, the amount of adsorbed Sr2+ was almost constant but 2?3 times smaller than at pH ?11. Further experiments were performed at the unadjusted pH since extreme alkaline conditions are environmentally hostile and inapplicable in real systems. The adsorption capacity of all the investigated adsorbents toward Sr2+ was similar under the investigated conditions, regardless of significant differences in the specific surface areas. It was shown and confirmed by the Dubinin?Radushkevich model that the cation exchange mechanism was the dominant mechanism of Sr2+ adsorption. Their developed microporous structures contributed to the Sr2+ adsorption process. The adsorption kinetics obeyed the pseudo-second-order model. The isotherm data were best fitted with the Langmuir isotherm model.

scholarly journals Synthesis Fe3O4/Talc nanocomposite by coprecipition-ultrasonication method and advances in hexavalent chromium removal from aqueous solution

2020 ◽  
Vol 38 (9-10) ◽  
pp. 483-501
Author(s):  
Nguyen Thi Huong ◽  
Nguyen Ngoc Son ◽  
Vo Hoang Phuong ◽  
Cong Tien Dung ◽  
Pham Thi Mai Huong ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Process ◽  
Low Cost ◽  
Batch Experiments ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Langmuir And Freundlich Equations

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.

Valorisation of Waste Mussel Shells as Biosorbent for an Azo Dye Elimination

2019 ◽  
Vol 800 ◽  
pp. 187-192 ◽  
Author(s):  
Halima Delali ◽  
Djilali Redha Merouani ◽  
Hakim Aguedal ◽  
Mustapha Belhakem ◽  
Abdelkader Iddou ◽  
...  
Keyword(s):  
Low Cost ◽  
X Ray Diffraction ◽  
Order Model ◽  
Batch Mode ◽  
Icp Ms ◽  
Orange G ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Mussel Shells ◽  
Good Agreement

In the present study, the waste shells were used as a new low cost and eco-friendly biosorbant for Orange G anionic dye removal from aqueous solutions. Experiments were conducted in batch mode, and the effect of pH of solution, contact time, and initial dye concentration. X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and ICP-MS analysis for chemical analysis were used to characterize the obtained biosorbent. The results showed that the mussel shells are composed 73% of calcite and 26% of aragonite with some traces of aluminum, magnesium, sodium, silicium and zinc. The biosorption results show that the optimal pH was around 2 for efficient Orange G biosorption. The equilibrium was attained in 60 min. The kinetic analysis showed that the pseudo-second-order model is in good agreement with the experimental data. The biosorption isotherm was well described by Langmuir isotherm model, the maximumbiosorption capacity was 1000mg/g. The thermodynamic study revealed that the biosorption of Orange G onto mussel shell is spontaneous and exothermic.

scholarly journals Equilibrium and Kinetic Study of Removal Copper(II) from Aqueous Solution Using Chicken Eggshells: Low Cost Sorbent

Molekul ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 28
Author(s):  
Mohammad Jihad Madiabu ◽  
Joko Untung ◽  
Imas Solihat ◽  
Andi Muhammad Ichzan
Keyword(s):  
Aqueous Solution ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Sorption Process ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Adsorption Condition ◽  
Pseudo Second Order ◽  
Effect Of Copper

The research aims to investigate feasibility eggshells as potential adsorbent to remove copper(II) ions from aqueous solution. Eggshells powder was characterized using X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. Effect of copper(II) initial concentration, adsorbent dosage, and contact time have conducted. The optimum adsorption condition obtained when 0.7 g eggshells applied to 50 mg/L copper(II) solution for 50 minutes. The maximum percentage of copper(II) removal was exceeded more than 85%. Langmuir and Freundlich isotherm model were applied to describe the equilibrium adsorption. Copper(II) kinetics sorption process was fitted to pseudo-second order model with a rate constant equal to 0.516 g/mg.min. The results clearly exhibit that eggshells powder can be effectively used to remove copper(II) ions from aqueous solutions.

Synthesis, Characterization and Comparative Study of TiO2 and ZnO Nanoparticles and their Application as a Photocatalysts for a Trichromatic Dye

2020 ◽  
Vol 5 (3) ◽  
pp. 252-268
Author(s):  
Meriem Kouhail ◽  
El Ahmadi Zakia ◽  
Benayada Abbes
Keyword(s):  
Zno Nanoparticles ◽  
Diffuse Reflectance Spectroscopy ◽  
Dye Degradation ◽  
Sol Gel ◽  
Solar Irradiation ◽  
Operational Parameters ◽  
X Ray Diffraction ◽  
Aquatic Life ◽  
X Ray ◽  
Uv Visible

Background: The textile industrial effluents cause profound imbalances in ecosystems, when released into nature; dyes are oxidized by micro-organisms, resulting in a decrease in the dissolved oxygen, which is necessary for the aquatic life. For this reason, it is important to implement economic, efficient, and green methods ensuring both the discoloration and detoxification of water. Objective: TiO2 and ZnO nanoparticles were synthesized by sol-gel and precipitation methods, respectively. These two nanoparticles were used to compare photocatalytic degradation under UV and solar irradiation for three reactive azoic dyes (trichromatic): Reactive Bezactive Yellow (RBY), Reactive Bezactive Red (RBR), and Reactive Bezactive Blue (RBB). Methods: The structural, i.e., morphological surface properties of the synthesized photocatalysts were characterized by Fourier Transform Infrared, X-ray diffraction, UV-Visible diffuse reflectance spectroscopy, and Scanning Electron Microscopy. : X-ray diffraction shows that TiO2 has a tetragonal structure with an anatase form. The effects of some operational parameters, such as the amount of TiO2 and ZnO, initial dye concentration, dye mixtures, and pH, were examined. The progress of photodegradation reaction was monitored by UV-Visible spectroscopy for decolorization and by High-Performance Liquid Chromatography for degradation, and the efficiency of degradation was confirmed by Chemical Oxygen Demand measurement. Results: The dye degradation was found to be better in the presence of solar irradiation than under UV irradiation. The photocatalytic activity of ZnO was higher than TiO2 when used in its optimal conditions. Conclusion: The percentage of degradation of each dye is different, and the order of degradation of the three reactive dyes is as follows: RBY> RBR> RBB.

scholarly journals Adsorption of Cationic Contaminants by Cyclodextrin Nanosponges Cross-Linked with 1,2,3,4-butanetetracarboxylic Acid and Poly(vinyl alcohol)

Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 342
Author(s):  
Ekkachai Martwong ◽  
Santi Chuetor ◽  
Jatupol Junthip
Keyword(s):  
Vinyl Alcohol ◽  
Physicochemical Characteristics ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Cyclodextrin Nanosponges ◽  
Pseudo Second Order ◽  
Regeneration Times ◽  
Butanetetracarboxylic Acid

Cationic organic pollutants (dyes and pesticides) are mainly hydrosoluble and easily contaminate water and create a serious problem for biotic and abiotic species. The elimination of these dangerous contaminants from water was accomplished by adsorption using cyclodextrin nanosponges. These nanosponges were elaborated by the cross-linking between 1,2,3,4-butanetetracarboxylic acid and β-cyclodextrin in the presence of poly (vinyl alcohol). Their physicochemical characteristics were characterized by gravimetry, acid-base titration, TGA, 13C NMR, ATR-FTIR, Raman, X-ray diffraction, and Stereomicroscopy. The BP5 nanosponges displayed 68.4% yield, 3.31 mmol/g COOH groups, 0.16 mmol/g β-CD content, 54.2% swelling, 97.0% PQ removal, 96.7% SO removal, and 98.3% MG removal for 25 mg/L of initial concentration. The pseudo-second-order model was suitable for kinetics using 180 min of contact time. Langmuir isotherm was suitable for isotherm with the maximum adsorption of 120.5, 92.6, and 64.9 mg/g for paraquat (PQ), safranin (SO), and malachite green (MG) adsorption, respectively. Finally, the reusability performance after five regeneration times reached 94.1%, 91.6%, and 94.6% for PQ, SO, and MG adsorption, respectively.

scholarly journals Adsorption of reactive blue BF-5G dye on MCM-41 synthesized from Chocolate clay

Cerâmica ◽  
2020 ◽  
Vol 66 (379) ◽  
pp. 269-276
Author(s):  
L. N. R. de Paula ◽  
G. M. de Paula ◽  
M. G. F. Rodrigues
Keyword(s):  
Adsorption Equilibrium ◽  
Acid Leaching ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Order Model ◽  
Freundlich Model ◽  
X Ray ◽  
Silica Source ◽  
Pseudo Second Order ◽  
Mcm 41

Abstract The efficiency of as-synthesized and calcined mesoporous silica, using clay as a silica source, to remove the reactive blue BF-5G dye was investigated. The materials were characterized by X-ray diffraction (XRD) analysis, energy-dispersive X-ray fluorescence (ED-XRF), and Fourier-transform infrared spectroscopy. The kinetic and adsorption isotherms were also studied. The XRD and ED-XRF results showed that the Chocolate clay is rich in SiO2 (69.4%) and has a large amount of other oxides, which can be eliminated by acid leaching. According to the characterization results, the MCM-41 synthesis was effective and produced a highly-ordered material. The kinetic study showed the adsorption corresponded predominantly to the pseudo-second order model. Adsorption equilibrium was reached after 3 h, and the data were better fitted to the Freundlich model. Furthermore, both samples obtained satisfactory removal results, being potential adsorbents having reduced cost due to the use of an alternative silica source.

scholarly journals Synthesis of Hybrid Organic-Inorganic Hydrotalcite-Like Materials Intercalated with Duplex Herbicides: The Characterization and Simultaneous Release Properties

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 5086
Author(s):  
Sheikh Ahmad Izaddin Sheikh Mohd Ghazali ◽  
Is Fatimah ◽  
Farah Liyana Bohari
Keyword(s):  
Controlled Release ◽  
Basal Spacing ◽  
X Ray Diffraction ◽  
Order Model ◽  
Release Formulation ◽  
X Ray ◽  
Release Property ◽  
Pseudo Second Order ◽  
Dichlorophenoxy Acetic Acid ◽  
Double Hydroxides

In this study, a controlled-release formulation of duplex herbicides, namely, 2,4,5-trichlorophenoxybutyric acid (TBA) and 3,4-dichlorophenoxy-acetic acid (3,4D), was simultaneously embedded into Zn-Al-layered double hydroxides (LDHs). The resulting nanohybrid Zinc-Aluminium-3,4D-TBA (ZADTX) was composed of a well-ordered crystalline layered structure with increasing basal spacing from 8.9 Å to 20.0 Å in the Powder X-ray Diffraction (PXRD) with 3,4D and TBA anions located in the gallery of LDHs with bilayer arrangement. The release of 3,4D and TBA fit the pseudo-second-order model. This duplex nanohybrid possessed a well-controlled release property (53.4% release from TBA and 27.8% release from 3,4D), which was highly effective, requiring the use of a small quantity and, hence, environmentally safer.

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