scholarly journals High Photocatalytic Performance of Modified Bismuth Oxychloride Semiconductor under Sunlight

2021 ◽  
Vol 37 (4) ◽  
pp. 770-778
Author(s):  
Preeja. P. Thattil ◽  
A. Leema Rose
Keyword(s):  
Dye Degradation ◽  
Diffuse Reflectance Spectrum ◽  
Ultra Violet ◽  
Analytical Techniques ◽  
Kinetic Studies ◽  
Degradation Process ◽  
Bet Surface Area ◽  
X Ray ◽  
Bismuth Oxychloride ◽  
Potential Applications

In recent years, the bismuth compounds have gained much interest due to their potential applications in the field of Photocatalysis. In our present work, Bismuth oxychloride Photocatalyst and Aluminium fluoride doped Bismuth oxychloride photocatalyst were synthesized by simple chemical methods using Bismuth nitrate pentahydrate as the precursor. The synthesized photocatalysts were characterized by different analytical techniques such as X-ray diffraction analyses, Ultra Violet –Diffuse reflectance spectrum, Field Emission – Scanning Electron Microscopy, Energy dispersive X-ray analyses,Fourier transform infrared spectroscopy studies and BET surface area analysis. The photocatalytic performances of the as-synthesized doped and undoped Bismuth oxychloride photocatalyst were tested towards the degradation of Acid green 1 dye. The parameters such as the effect of pH, catalyst concentration and initial dye concentration are optimized, and the kinetic studies are carried out for the photocatalytic dye degradation process. The experimental results showed that about 80% of the Acid green 1 dye got decolourized within 90 minutes by effective air purging under natural sunlight radiation in the presence of the AlF-BiOCl photocatalyst under optimized conditions.

Green synthesis, structural characterization, and catalytic activity of silver nanoparticles stabilized with Bridelia retusa leaf extract

2018 ◽  
Vol 7 (1) ◽  
pp. 30-37 ◽  
Author(s):  
Ramesh Vinayagam ◽  
Thivaharan Varadavenkatesan ◽  
Raja Selvaraj
Keyword(s):  
Silver Nanoparticles ◽  
Rhodamine B ◽  
Leaf Extract ◽  
Dye Degradation ◽  
Synthesis Method ◽  
Degradation Process ◽  
Spectroscopic Studies ◽  
Metallic Silver ◽  
X Ray ◽  
Bridelia Retusa

Abstract:An environmentally benign method to synthesize silver nanoparticles (SNPs) using the leaf extract ofBridelia retusawas developed. The UV-Vis absorption spectrum of the synthesized SNPs displayed a surface plasmon peak at 420 nm. Scanning electron microscopy (SEM) revealed the irregular shaped nanoparticles, and energy dispersive X-ray (EDX) ascertained the presence of metallic silver by showing a strong signal at 3 eV. The crystalline structure of metallic silver was confirmed by X-ray diffraction (XRD). The mean size of the SNPs was calculated as 16.21 nm. Fourier infrared (FT-IR) spectroscopic studies displayed specific bands for various functional groups and affirmed the function of reduction and stabilization of SNPs. The stability was endorsed by the zeta potential value of −18.1 mV. The results evidenced that this leaf extract-mediated synthesis method is eco-friendly, rapid, and cheap. The catalytic power of the SNPs was investigated for Rhodamine B dye degradation. The SNPs completely degraded Rhodamine B within 9 min; thus, the dye degradation process was very rapid. The pseudo-first order degradation constant was found out to be 0.1323 min−1. This paves the way for the future development of novel nano-catalysts to reduce environmental pollution.

scholarly journals Natural and Activated Allophane Catalytic Activity Based on the Microactivity Test in Astm Norm 3907/D3907M-2019

2020 ◽  
Vol 10 (9) ◽  
pp. 3035
Author(s):  
Edward Henry Jiménez Calderón ◽  
Ana Emperatriz Paucar Tipantuña ◽  
Paulina Fernanda Herrera Mullo ◽  
Daniel Alejandro Hidalgo Cháfuel ◽  
Washington Ruiz ◽  
...  
Keyword(s):  
Analytical Techniques ◽  
Bet Surface Area ◽  
Navier Stokes ◽  
Maximum Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Catalytic Activation ◽  
Atomic Force ◽  
Activating Agent

The optimal conditions of the catalytic activation of allophane were evaluated for possible use as a catalyst within a fluidized bed catalytic cracking unit (FCC). The physicochemical properties of natural allophane and activated allophane were studied by using an alkaline activating agent, followed by a hydrothermal treatment. For the characterization, analytical techniques were used: Fourier transform infrared spectroscopy, particle size, (BET) surface area, thermogravimetry (TGA), X-ray diffraction (XRD), chemisorption, X-ray fluorescence (XRF), atomic force microscopy (AFM), and chromatography. The catalytic evaluation was determined by the (MAT) micro activity test equipment constructed according to ASTM D-3907/D3907M-2019. In addition, the Navier–Stokes 3D equations (nonlinear partial derivatives) were studied, which allow studying molecular dynamics contributing substantively to chemical kinetics describing the process of decomposition of crude oil in thermal cracking, determining the maximum temperature at which it retains its properties through the action of heat.

PHOTOCATALYTIC DEGRADATION OF PYRENE IN POROUS Pt/TiO2–SiO2 PHOTOCATALYST SUSPENSION UNDER UV IRRADIATION

NANO ◽  
2008 ◽  
Vol 03 (05) ◽  
pp. 317-322 ◽  
Author(s):  
ZHAOHUI LUO ◽  
KEIKO KATAYAMA-HIRAYAMA ◽  
KIMIAKI HIRAYAMA ◽  
TETSUYA AKITSU ◽  
HIDEHIRO KANEKO
Keyword(s):  
Molecular Weight ◽  
Photocatalytic Degradation ◽  
High Molecular Weight ◽  
Uv Irradiation ◽  
Degradation Kinetics ◽  
Degradation Process ◽  
Bet Surface Area ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
X Ray

Pyrene is a high molecular weight polycyclic aromatic hydrocarbon (PAH) that is found in water systems worldwide. It is harmful to living organisms, even when taken in very small amounts. The photocatalytic degradation of pyrene in porous Pt / TiO 2– SiO 2 photocatalyst (PPtPC) suspension under UV irradiation was investigated in this study. PPtPC was prepared by a simple heat treatment of the compacted powder mixtures of anatase TiO 2 and amorphous SiO 2 with camphor as a pore directing template, followed by coating platinum by the dip-coating method. X-ray diffraction (XRD), scanning electron microscopy (SEM) with an integrated energy-dispersive analysis of the X-ray (EDX) system, and Brunauer–Emmett–Teller (BET) were used to characterize PPtPC. The degradation kinetics of pyrene in different experimental conditions, such as initial concentration of pyrene, oxygen concentrations, pH, and temperature, were investigated. The durability of PPtPC was also tested. The results indicate that the structure of TiO 2 in PPtPC is anatase. The aggregated size of PPtPC is in the range of 10–100 μm, the mean pore diameter is 3 nm, and the BET surface area is 109 m2 g-1. The photocatalytic degradation process of pyrene follows pseudo-first-order kinetics. The rate constants increase as the initial concentration of pyrene and pH decrease. Higher temperature slightly enhances the rate constant. The dissolved oxygen in the photocatalytic degradation process is not as important as in the photolysis process. The recovered PPtPC still shows high photoactivity. This work suggests that PPtPC offers a promising method for high molecular weight PAH removal.

scholarly journals Catalytic Removal of Alizarin Red Using Chromium Manganese Oxide Nanorods: Degradation and Kinetic Studies

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1150
Author(s):  
Muhammad Hamza ◽  
Ataf Ali Altaf ◽  
Samia Kausar ◽  
Shahzad Murtaza ◽  
Nasir Rasool ◽  
...  
Keyword(s):  
Kinetic Model ◽  
Manganese Oxide ◽  
Dye Removal ◽  
Dye Degradation ◽  
Uv Light ◽  
Kinetic Studies ◽  
Research Area ◽  
Alizarin Red ◽  
X Ray ◽  
Catalytic Removal

Dye removal through photocatalytic degradation employing nanomaterials as catalysts is a growing research area. In current studies, photocatalytic alizarin red (AR) dye degradation has been investigated by designing a series of Cr based manganese oxide nanomaterials (MH1–MH5). Synthesized nanomaterials were characterized by powder X-ray diffraction, scanning electron microscopy/energy dispersive x-ray, Brunauer–Emmett–Teller, and photoluminescence techniques and were utilized for photocatalytic AR dye degradation under UV light. AR dye degradation was monitored by UV–visible spectroscopy and percent degradation was studied for the effect of time, catalyst dose, different dye concentrations, and different pH values of dye solution. All the catalysts have shown more than 80% dye degradation exhibiting good catalytic efficiencies for dye removal. The catalytic pathway was analyzed by applying the kinetic model. A pseudo second-order model was found the best fitted kinetic model indicating a chemically-rate controlled mechanism. Values of constant R2 for all the factors studied were close to unity depicting a good correlation between experimental data.

scholarly journals Correlations Between Alkali and Crystallinity in lyocell-Based ACF Probed with X-Ray Diffraction

2020 ◽  
Vol 58 (7) ◽  
pp. 495-500
Author(s):  
Young Min Jin ◽  
Joon Hyuk Lee ◽  
Sang Sun Choi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Thermal Characteristics ◽  
Degree Of Crystallinity ◽  
Bet Surface Area ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Areas ◽  
Potential Applications ◽  
Activated Carbon Fibres

This study examined the effect of alkalis on lyocell-based activated carbon fibres (ACFs) with high Brunauer-Emmett-Teller (BET) surface areas, using X-ray diffraction (XRD). Here, alkali treatments were conducted using 10 ~ 25 % NaOH and KOH on lyocell samples for 3 h at ambient room temperature. A secondary treatment with 4 % each of KOH and H3PO4 for an additional 3 h followed. An activated form of the samples was prepared by oxidation (stabilisation), carbonisation, and activation. The final ACF form of the samples showed a porous structure with high BET surface areas (> 1,000 m<sup>2</sup> g<sup>-1</sup>). A 25 % dosage of NaOH produced the highest BET surface area compared to other samples. In terms of crystallinity, a 15 % dosage of KOH was found to be the optimum dosage to secure the highest degree of crystallinity among all samples. Meanwhile, the NaOH was successfully shifted the samples into the most distinct form of cellulose II. 15 % NaOH was found to secure the most stable thermal characteristics, as determined via thermo-gravimetric analysis. The present work demonstrates the various physio-chemistries of ACFs prepared with different proportions and types of alkalis, leading to intriguing potential applications.

scholarly journals Sunlight Assisted Degradation of Methylene Blue as a Model Dye using Bismuth Oxychloride Nanoparticles: Ecofriendly and Industry Efficient Photocatalysis for Waste Chemical Treatment

2019 ◽  
Vol 32 (1) ◽  
pp. 115-121
Author(s):  
Chandan Adhikari ◽  
Mandeep Kaur ◽  
Ravichandran
Keyword(s):  
Methylene Blue ◽  
Dye Degradation ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Bismuth Oxychloride ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Different Types ◽  
Photocatalytic Dye Degradation ◽  
Uv Visible

In this study, an efficient sunlight triggered dye degradation was demonstrated using methylene blue as a model dye and bismuth oxychloride nanoparticles were used as photocatalyst. Two different types of nanoparticles, nanoflower and nanodisk, were prepared to understand the effect of morphology on the photocatalysis. Both the particles were prepared following a straightforward and easy methodology from readily available chemicals. The particles were characterized using scanning electron microscope, Fourier transformed infrared spectroscopy, powder X-ray diffraction. UV-visible spectroscopy and colorimeter were used to evaluate the photocatalytic activity of the catalyst. Both the nanoparticles were able to degrade the dye completely within 3-4 h under visible light. The photocatalytic rate constant analysis demonstrates that out of two morphology, nanoflower is found to be more effective than nanodisk towards dye degradation. The sunlight was also used to understand whether the photocatalyst can degrade the dye or not in presence of sunlight only. Both nanoparticles were able to degrade the dye 100 % in presence of sunlight within maximum 4 h. The photocatalytic dye degradation in presence of sunlight was conducted in between 10 a.m. to 4 p.m. when the maximum amount of sunlight is available with high intensity and energy. The catalysts were 100 % active after the first cycle and upto four cycles the dye degradation efficiency remain around 60-80%. The study demonstrates that sunlight can degrade the dye in presence of these photocatalyst which clearly indicates its energy saving approach thus making it more economic and green methodology for the industries.

ZnS NANOFLOWERS ON GRAPHENE FOR USE AS A HIGH-PERFORMANCE PHOTOCATALYST

NANO ◽  
2014 ◽  
Vol 09 (08) ◽  
pp. 1450097 ◽  
Author(s):  
ZENG BIN ◽  
LONG HUI
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Dye Degradation ◽  
Uv Light ◽  
Xps Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Potential Applications

The nanocomposites of graphene loaded– ZnS nanoflowers (GR– ZnS ) had been successfully prepared. Materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS) spectra. A possible formation mechanism of this architecture was proposed. The experimental results revealed that these nanoflowers exhibited excellent UV-light photocatalytic activities for pollutant methyl orange (MO) dye degradation. These new nanostructures were expected to show considerable potential applications in the water treatment.

scholarly journals Au/TiO2Reusable Photocatalysts for Dye Degradation

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Silija Padikkaparambil ◽  
Binitha Narayanan ◽  
Zahira Yaakob ◽  
Suraja Viswanathan ◽  
Siti Masrinda Tasirin
Keyword(s):  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Dye Degradation ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dye Pollutants ◽  
Transmission Electron ◽  
Uv Visible

Nanogold doped TiO2catalysts are synthesized, and their application in the photodegradation of dye pollutants is studied. The materials are characterized using different analytical techniques such as X-ray diffraction, transmission electron microscopy, UV-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The results revealed the strong interaction between the metallic gold nanoparticles and the anatase TiO2support. Au doped systems showed very good photoactivity in the degradation of dye pollutants under UV irradiation as well as in sunlight. A simple mechanism is proposed for explaining the excellent photoactivity of the systems. The reusability studies of the photocatalysts exhibited more than 98% degradation of the dye even after 10 repeated cycles.

scholarly journals Removal of methyl orange by heterogeneous fenton process using iron dispersed on alumina pillared bentonite pellet

2020 ◽  
Vol 23 (2) ◽  
pp. First
Author(s):  
Ngo Thi Thuan ◽  
Tran Tien Khoi ◽  
Nguyen Thi My Chi ◽  
Nguyen Ngoc Vinh
Keyword(s):  
Methyl Orange ◽  
Surface Area ◽  
Dye Degradation ◽  
Catalyst Activity ◽  
Cod Removal ◽  
Bet Surface Area ◽  
Catalyst Loading ◽  
Fenton Process ◽  
Heterogeneous Fenton ◽  
X Ray

Introduction: Heterogeneous Fenton is one of the Advanced Oxidation Processes (AOPs) and has been proven to be effective on azo dye degradation. However, a low-cost catalyst and factors affecting the processes of this system were further investigated. Methods: In this study, pellets of iron alumina pillared bentonite (PFeAPB) were prepared by dispersing iron ions on alumina pillared bentonite pellet. Catalyst activity and lifetime were investigated via efficiencies of Methyl Orange (MO) decolorization and Chemical Oxygen Demand (COD) removal, a typical dye type of textile wastewater. Characteristics of the PFeAPB catalyst were examined by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, and X-ray fluorescence (XRF). Results: Results of batch experiments showed that specific surface area of the PFeAPB catalyst was 111.22 m2/g higher than its precursor by 2 times (57.79 m2/g). Goethite, Hematite and Maghemite phases with approximately 11.5% of iron elements containing in the catalyst were detected via XRD and XRF. Experimental conditions of pH, initial MO solution, Hydrogen Peroxide concentration, reaction time and catalyst loading were 2.0 ± 0.1, 12.7 mmol/L, 150 min and 20 g/L, respectively, to achieve 88.68 ± 5.69% of MO decolorization and 50.27 ± 6.05% of COD removal while dissolved iron in this heterogeneous Fenton process was below standard limit (2 ppm). Catalyst activity decreased by 5.22% in decolorization efficiency after the two first reusages. Conclusion: These primary results showed the potential of applying PFeAPB catalyst in heterogeneous Fenton process with low iron leaching into water.  

scholarly journals Ultraviolet Radiation/persulphate/hydrogen Peroxide Treatment System for Acid Blue 80 Dye Degradation of Batch Flow Chemical Reactor: Effects of Operational Parameters, Mineralisation, Energy Consumption, and Kinetic Studies

2021 ◽  
Author(s):  
Tariq Al–Musawi ◽  
Murat Yilmaz ◽  
Amir Mahvi ◽  
Samaneh Mohebi ◽  
davoud balarak
Keyword(s):  
Hydrogen Peroxide ◽  
Energy Consumption ◽  
Dye Degradation ◽  
Kinetic Studies ◽  
Chemical Reactor ◽  
Degradation Process ◽  
Reaction Rate Constant ◽  
The Other ◽  
Operational Parameters ◽  
Acid Blue

Abstract This study offers a comprehensive investigation into the efficiency of degradation of acid blue 80 (AB80) dye using a system using ultraviolet (UV) radiation combined with hydrogen peroxide (H2O2) and persulphate (PS) oxidants (UV/PS/H2O2). The degradation reactions were performed under different values of PS and H2O2 concentrations, initial AB80 dye concentration, pH, UV intensity, and contact time. The results revealed that the UV/H2O2 provided the best performance at pH of 5, while the best performance for the UV/PS and UV/PS/H2O2 systems was obtained at pH of 7. Besides, 15 mmol was found to be the optimum concentration for both oxidants. The efficiency of the combined process of the UV/PS/H2O2 was higher than that of the other two processes i.e., UV/PS and UV/H2O2, which was 98.2% for a dye concentration of 25 mg/L. Further, the BOD5/COD ratios at the beginning and end of the UV/PS/H2O2 process were 0.19 and 0.52, respectively, indicative of the conversion of the non-biodegradable dye molecules to biodegradable compounds. The toxicity test was performed using the bioassay method with Daphnia magna, and 90% reduction in toxicity was observed in the effluent. The lethal concentration 50 (LC50) indicator was found to be 4.7 mg/L for the dye solution. The results also revealed that the degradation data followed the pseudo-first-order kinetics, and the reaction rate constant was higher for the UV/PS/H2O2 system than for the other systems. The rate of mineralisation by this process was 0.92. Scavenging studies also showed that both the sulphate (SO°-4) and hydroxyl (OH°) radicals play an important role in the degradation process. Energy consumption in the UV/H2O2, UV/PS, and UV/PS/H2O2 processes was 61, 47.8, and 20.8 kWh/m3, respectively. On conclusion, the UV/PS/H2O2 is an effective and applicable process for the treatment of dye in wastewater, particularly when the medium is neutral.

Sign in / Sign up

Export Citation Format

Share Document