Removal of methylene blue from water by γ-MnO2

2011 ◽  
Vol 64 (4) ◽  
pp. 899-903 ◽  
Author(s):  
W. H. Kuan ◽  
C. Y. Chen ◽  
C. Y. Hu
Keyword(s):  
Methylene Blue ◽  
Organic Carbon ◽  
Room Temperature ◽  
Oxidative Degradation ◽  
Dramatic Decrease ◽  
Dimethylamino Group ◽  
X Ray ◽  
Toc Removal ◽  
Acidic Conditions ◽  
Ph Conditions

Methylene blue (MB) is a cationic dyestuff, which is particularly resistant to biodegradation. The molecular sieved γ-MnO2 was used as an adsorbent/oxidant to remove the MB at room temperature and in visible light. The removal efficiency was mainly evaluated by X-ray diffractometer (XRD), UV–Vis spectrometer (UV–Vis), total organic carbon (TOC). The results revealed that the mechanisms of MB removal by γ-MnO2 are significantly influenced by the pH. In acidic conditions, hypsochromic effects (i.e. blue shifts of UV–Vis spectra) resulting from N-demethylation of the dimethylamino group in MB may occur concomitantly with oxidative degradation by γ-MnO2. However, the TOC in solution after γ-MnO2 treatment in acidic conditions did not show a dramatic decrease. At near neutral pH conditions, there was almost no UV–Vis absorption for the MB solution, however, only 50% TOC removal was observed. It indicated that MB was not only adsorbed onto γ-MnO2 but also partially oxidatively degraded to other organic compounds which were colourless for UV–Vis.

scholarly journals Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 558
Author(s):  
Wenhui Zhu ◽  
Caiyun Zhang ◽  
Yali Chen ◽  
Qiliang Deng
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Degradation Rate ◽  
Model Compound ◽  
Vibrating Sample Magnetometer ◽  
Simulated Sunlight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

In Situ Synchrotron X-Ray Diffraction Study of a Deformed Cu-Fe-P Alloy during Heating

2016 ◽  
Vol 850 ◽  
pp. 191-196 ◽  
Author(s):  
Wei Wang ◽  
Cun Lei Zou ◽  
Ren Geng Li ◽  
Wen Wen ◽  
Hui Jun Kang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Lattice Distortion ◽  
Copper Matrix ◽  
Heating Process ◽  
Recrystallization Process ◽  
Full Width ◽  
X Ray Diffraction ◽  
Dramatic Decrease ◽  
X Ray

In situ synchrotron X-ray diffraction was used to study a deformed Cu-0.88 Fe-0.24 P alloy during heating process. The measurements were performed at room temperature and also at high temperatures up to 893 K in order to determine the recovery, ageing and recrystallization process. With the increase of temperature, the angles of copper matrix peaks moved left and the FWHM (full width at half maximum) decreased slightly. Fe3P precipitates were first detected at 533 K, reached the maximum at 673 K, and re-dissolved into matrix at 853 K. A dramatic decrease in FWHM was observed accompanied by the precipitation of Fe3P phases, indicating the reduction of lattice distortion of copper matrix.

scholarly journals Radiation Crosslinking of Polyurethanes: Characterization by FTIR, TGA, SEM, XRD, and Raman Spectroscopy

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Mohamed Mohamady Ghobashy ◽  
Zizi I. Abdeen
Keyword(s):  
Gamma Radiation ◽  
Room Temperature ◽  
Soft Segment ◽  
Oxidative Degradation ◽  
Radiation Doses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Color Changes ◽  
Radiation Crosslinking ◽  
Solid Film

Gamma radiation can be used for enhancing the physical properties of polyurethane (PU). Radiation was used to crosslink a polyurethane at room temperature; four samples of the PU solid film are irradiated at variable four radiation doses 0, 50, 100, and 150 kGy under vacuum conditions. Crosslinking radiation is more common than oxidative degradation and crosslinking is believed to be more efficient in the soft segment of PU. The structure of the PUs is performed by Fourier transform infrared (FTIR-ATR), Thermogravimetric Analysis (TGA-DTG), and X-ray Diffraction (XRD) which have been used to investigate the effect of gamma radiation on the polyurethane (PU). The results showed that the radiation crosslinking of polyurethanes improved the thermal stability and the crystallinity. The microstructure modifications of polyurethane samples have also been studied as a function of the dose using the scanning electron microscope (SEM). The effects of gamma irradiation on the color changes of polyurethane were observed. The irradiated PUs have conjugated structure and are capable of emitting purple fluorescence.

Photocatalytic degradation of methylene blue on magnetically separable FePc/Fe3O4 nanocomposite under visible irradiation

2009 ◽  
Vol 81 (12) ◽  
pp. 2327-2335 ◽  
Author(s):  
Kun Wang ◽  
Lixia Yu ◽  
Sheng Yin ◽  
Henan Li ◽  
Huaming Li
Keyword(s):  
Magnetic Field ◽  
Methylene Blue ◽  
Oxidative Degradation ◽  
High Catalytic Activity ◽  
Iron Phthalocyanine ◽  
X Ray ◽  
Transmission Electron ◽  
Visible Irradiation ◽  
Magnetically Separable ◽  
Catalytic Cycles

A novel magnetically separable photocatalyst iron phthalocyanine/Fe3O4 (FePc/Fe3O4) nanocomposite was easily prepared by an organic–inorganic complexation technique, and characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and Fourier transform-infrared (FTIR). This functional nanocomposite has been found to exhibit high catalytic activity in the presence of added hydrogen peroxide, for oxidative degradation of methylene blue (MB) under visible light irradiation. Under these conditions, MB (10 mg/l) underwent about 78 % oxidation in 2 h, and the catalyst still retained high activity after five catalytic cycles. Intervening recovery was easily achieved by changing the external magnetic field.

scholarly journals Removal of Various Hazardous Materials Using a Multifunctional Biomass-Derived Hydroxyapatite (HAP) Catalyst and Its Antibacterial Effects

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3302
Author(s):  
Sanha Jang ◽  
Kyeongmun Park ◽  
Sehwan Song ◽  
Haksoo Lee ◽  
Sungkyun Park ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Room Temperature ◽  
Hazardous Materials ◽  
Antibacterial Effects ◽  
E Coli ◽  
Phosphate Ion ◽  
High Metal ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
Maximum Removal

In the present study, oyster shells, a cause of environmental pollution, were employed effectively to synthesize hydroxyapatite (HAP) by facile oxidation and phosphorylation. The ability of HAP to adsorb various metal cations and inhibit bacterial growth was validated. The biomass-derived HAP catalyst exhibited high metal cation adsorption in water at room temperature and under various acidic conditions (M = Cr, Mn, Ni, Cu, Cd, Ba, and Pb). HAP was demonstrated to have a maximum removal efficiency of 92.8% for the heavy metal Pb. Even under different pH conditions, HAP was demonstrated to be effective for the removal of three harmful heavy metals, Cr, Cd, and Pb, with a particularly high removal efficiency demonstrated for Pb under all conditions (average removal efficiency of Cr: 63.0%, Cd: 59.9%, and Pb: 91.6%). In addition, HAP had a significant influence on phosphate ion adsorption in aqueous solution, eliminating 98.1% after 3 min. Furthermore, biomass-derived HAP was demonstrated to have significant antibacterial activity against E. coli and S. aureus (5 mM: 74% and 78.1%, 10 mM: 89.6% and 96.0%, respectively).

Facile Fabrication of Taper-Like BiVO4 Nanorods with High Photocatalytic Property under Sunlight Irradiation

2010 ◽  
Vol 96 ◽  
pp. 87-92 ◽  
Author(s):  
Lin Rui Hou ◽  
Chang Zhou Yuan
Keyword(s):  
Methylene Blue ◽  
Room Temperature ◽  
Degradation Mechanism ◽  
Photocatalytic Property ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
Sunlight Irradiation ◽  
X Ray ◽  
Synthetic Strategy ◽  
Facile Fabrication

We report the synthesis of the taper-like BiVO4 nanorods by employing a solid-state grinding synthetic strategy. The X-ray diffraction (XRD) indicates that the as-prepared BiVO4 nanorods were crystallized in a monoclinic system. The diameter and length of taper-like nanorods are confirmed by the scanning electron microscopy (SEM) technology. The diameter and length of the taper-like nanorods are 100 nm and 1 μm, respectively. And the photocatalytic activity of the taper-like BiVO4 nanorods was evaluated by measuring the degradation of methylene blue (MB) in water under sunlight irradiation. MB was degraded nearly to nothing under sunlight irradiation for 120 min at room temperature in air. These results indicate the as-prepared product is a good sun-driven photocatalyst. In addition, the degradation mechanism of methylene blue over BiVO4 nanorods was tentatively investigated.

Kinetics and Adsorption Model of Methylene Blue on [email protected] Nanoplate Composite

2021 ◽  
Author(s):  
Le Manh Cuong ◽  
Bui Hoang Duc ◽  
Pham Van Thang ◽  
Nguyen Thi Tuyet Mai ◽  
Huynh Dang Chinh ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Room Temperature ◽  
Diffuse Reflectance Spectroscopy ◽  
Orthorhombic Phase ◽  
Precipitation Method ◽  
Blue Dye ◽  
Adsorption Model ◽  
X Ray ◽  
Composite Adsorbents ◽  
Generation Activity

[email protected] nanoplate composite adsorbents were prepared in a simple acid precipitation method at room temperature. The [email protected] nanoplate composite adsorbents were characterized by X-ray powder diffraction, micro-Raman spectroscopy, Fourier transform infrared spectra, scanning electron microscopy and UV-vis diffuse reflectance spectroscopy. The results show that the orthorhombic-phase WO3.H2O nanoplates with dimensions of [Formula: see text][Formula: see text]nm3 were successfully composited with g-C3N4. The methylene blue dye generation activity of these adsorbents was evaluated. The kinetics and absorption model of [email protected] nanoplate composite adsorbents were further studied.

scholarly journals Room Temperature Synthesis of Nanostructured ZnO: Active Visible Photocatalyst in the Degradation of Methylene Blue

2021 ◽  
pp. 13-20
Author(s):  
Amine El Farrouji ◽  
Rachid Mohamed Tchalala ◽  
Abderrahim Chihab Eddine ◽  
Ahmad Mehdi ◽  
Larbi El Firdoussi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Methylene Blue ◽  
Room Temperature ◽  
Phase Method ◽  
Zno Nps ◽  
Experimental Conditions ◽  
X Ray ◽  
Transmission Electron ◽  
Solution Phase Method ◽  
Kinetics Of

Nanostructured ZnO was prepared using a facile solution-phase method at room temperature without need to calcination. Oxidation of zinc sulfate by sodium hypochlorite in the presence of polyethylene glycol (PEG) and sodium hydroxide (NaOH) gave pure nanostructured zinc oxide (ZnO-NPs). The structure and physicochemical properties of the material were determined by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (IR), Energy Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV–Vis diffuse reflectance and their optical Properties. ZnO particles were successfully distributed in two-dimensional sheet with a nanometric thickness and a random distribution. The activity was evaluated for photocatalytic degradation of methylene blue (MB) by a study of experimental conditions such as the effect of the mass of the catalyst, the effect of the initial concentration of the dye and the effect of the volume of the oxidizing agent. The kinetics of the reaction follow a pseudo-first order.

The surprising formation of structurally distorted ap-9-(o-tert-butylphenyl)-9-methylthiofluorene and its facile homolysis into sp-9-(o-tert-butylphenyl)-3-methylthiofluorene and sp-9-(o-tert-butylphenyl)fluorene

1999 ◽  
Vol 77 (5-6) ◽  
pp. 960-966 ◽  
Author(s):  
Yuqing Hou ◽  
Cal Y Meyers
Keyword(s):  
Room Temperature ◽  
Elevated Temperatures ◽  
Dynamic Nmr ◽  
X Ray Diffraction ◽  
Similar Treatment ◽  
X Ray ◽  
Butyl Group ◽  
Tert Butyl Group ◽  
Acidic Conditions ◽  
Bulk Effect

The continued study of rotationally restricted 9-(o-tert-butylphenyl)fluorenes has provided surprising results. Treatment of sp-9-(o-tert-butylphenyl)-9-fluorenol (1) with ethanol or methanol under acidic conditions affords sp-9-(o-tert-butylphenyl)-9-ethoxyfluorene (2b) and sp-9-(o-tert-butylphenyl)-9-methoxyfluorene (3b), respectively, but similar treatment with methanethiol converts 1 into the rotamerically opposite ap-9-(o-tert-butylphenyl)-9-methylthiofluorene (4a). While all three products reflect reaction with inversion at C-9, 2b and 3b reflect subsequent rotation, which is not the case with 4a. X-ray diffraction shows 4a to be highly distorted and strained, but apparently favored thermodynamically over its sp rotamer. Homolysis of 4a is observed at room temperature, and at elevated temperatures accounts for the formation of sp-9-(o-tert-butylphenyl)fluorene (6b) and sp-9-(o-tert-butylphenyl)-3-methylthiofluorene (7c) as major products. X-ray diffraction shows 6b and 7c to be virtually devoid of distortion. Methylation of 6b via its anion also proceeds with inversion without rotation to form ap-9-(o-tert-butylphenyl)-9-methylfluorene (4c). Dynamic NMR unexpectedly showed that in these ap configurations 9-CH3 (of 4c) has a greater bulk effect than 9-CH3S (of 4a) in forcing the o-tert-butyl group into the fluorene plane.Key words: fluorene, rotamer, distortion, homolysis, carbanion, carbocation, radical.

scholarly journals Simultaneous Removal and Recovery of Metal Ions and Dyes from Wastewater through Montmorillonite Clay Mineral

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1699 ◽  
Author(s):  
Filippo Parisi ◽  
Giuseppe Lazzara ◽  
Marcello Merli ◽  
Stefana Milioto ◽  
Francesco Princivalle ◽  
...  
Keyword(s):  
Metal Ions ◽  
Langmuir Model ◽  
Water Remediation ◽  
X Ray Diffraction ◽  
Freundlich Model ◽  
X Ray ◽  
Adsorption Sites ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
Montmorillonite Nanoclay

The main objective of this work was to evaluate the potential of Montmorillonite nanoclay (Mt), readily and inexpensively available, for the simultaneous adsorption (and removal) of two classes of pollutants: metal ions and dyes. The attention was focused on two “model” pollutants: Ce(III) and crystal violet (CV). The choice is due to the fact that they are widespread in wastewaters of various origins. These characteristics, together with their effect on human health, make them ideal for studies on water remediation. Moreover, when separated from wastewater, they can be recycled individually in industrial production with no or simple treatment. Clay/pollutant hybrids were prepared under different pH conditions and characterized through the construction of the adsorption isotherms and powder X-ray diffraction. The adsorption behavior of the two contaminants was revealed to be significantly different: the Langmuir model reproduces the adsorption isotherm of Ce(III) better, thus indicating that the clay offers a unique adsorption site to the metal ions, while the Freundlich model proved to be the most reliable for the uptake of CV which implies heterogeneity of adsorption sites. Moreover, metal ions do not adsorb at all under acidic conditions, whereas the dye is able to adsorb under all the investigated conditions. The possibility to modulate the adsorption features by simply changing the pH conditions was successfully employed to develop an efficient protocol for the removal and separation of the different components from aqueous solutions mimicking wastewaters.

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