Degradation of crystal violet over heterogeneous TiO2-based catalysts: The effect of process parameters

In this study, modified sol-gel method was employed to synthesize the pure and Zr-doped titania catalysts. Brunauer-Emmett-Teller (BET) method was applied to determine porosity, X-ray diffraction (XRD) analysis was used to study crystal structure, scanning electron microscopy (SEM) was used to investigate morphology and Fourier transform infrared spectroscopy (FTIR) was used to examine surface properties/total acidity of the obtained catalysts samples. Photocatalytic activity was tested in the reaction of crystal violet (CV) dye decolourization/degradation under UV light irradiation. The effects of several photocatalysis operational parameters were considered, such as catalyst dosage, initial dye concentrations, duration of UV irradiation treatment, as well as catalysts calcination temperatures and dopant amounts. The obtained results indicated faster dye decolourization/degradation with the increase of the catalyst dosage and the decrease of initial CV concentrations. The Zr-doping affects photocatalytic properties, i.e. CV decolourization/degradation of the prepared catalytic materials. Thus, addition of 5 wt.% of ZrO2 to titania increases photocatalytic effect for ~15% and addition of 10 wt.% of ZrO2 improves the photocatalytic efficiency of titania for nearly 30%.

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Decolorization of crystal violet over TiO2 and TiO2 doped with zirconia photocatalysts

Hemijska industrija ◽

10.2298/hemind160521036v ◽

2017 ◽

Vol 71 (3) ◽

pp. 259-269 ◽

Cited By ~ 1

Author(s):

Marija Vasic ◽

Marjan Randjelovic ◽

Jelena Mitrovic ◽

Nikola Stojkovic ◽

Branko Matovic ◽

...

Keyword(s):

Crystal Violet ◽

Uv Light ◽

Sol Gel ◽

Chemical Properties ◽

Dye Decolorization ◽

Operational Parameters ◽

Physico Chemical ◽

Irradiation Treatment ◽

Catalytic Material ◽

Reaction Cycles

Titania based catalyst and TiO2 doped with zirconia were prepared by modified sol?gel method. The synthesized catalysts samples were characterized by BET, XRD, SEM and FTIR techniques. Photocatalytic activity was tested in the reaction of crystal violet (CV) dye decolorization/decomposition under UV light irradiation. The effect of several operational parameters, such as catalyst dosage, initial dye concentrations, duration of UV irradiation treatment and number of reaction cycles were also considered. The obtained results indicated faster dye decolorization with the increase of the catalyst amount and a decrease of initial CV concentrations. An influence of doping with zirconia on the physico-chemical properties of bare titania was studied. The doping procedure had affected photocatalytic properties of the final catalytic material, and had improved photocatalytic performances of doped catalyst on crystal violet decolorization/degradation in comparison to bare titania.

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Activation of Cement Clinker as Catalysts for Transesterification Reaction of Palm Oil Off Grade to Biodiesel

Jurnal Rekayasa Kimia & Lingkungan ◽

10.23955/rkl.v14i2.14704 ◽

2019 ◽

Vol 14 (2) ◽

pp. 147-154

Author(s):

Karina Octaria Putri ◽

Dhani Nur Miftahudin ◽

Zuchra Helwani ◽

Syaiful Bahri

Keyword(s):

Calcination Temperature ◽

Batch Reactor ◽

Xrd Analysis ◽

Transesterification Reaction ◽

Cement Clinker ◽

Gas Chromatography Mass Spectrometry ◽

Solid Base ◽

Calcination Temperatures ◽

Bet Analysis ◽

Catalyst Dosage

Calcium oxide (CaO) is a heterogeneous solid base which is generally used as a catalyst in making biodiesel. It is mainly obtained from cement clinker and activated through calcination method. The purpose of this study was to determine the effect of using cement clinker catalyst on the yield of the biodiesel. A batch reactor with a condenser was used in making the biodiesel under favorable conditions such as calcination temperatures of 700 °C, 750 °C and 800 °C, time of 5, 6 and 7 hours, and catalyst concentration of 1%-w, 2%-w, and 3%-w oil. The analysis involved X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET) for catalysts and Gas Chromatography-Mass Spectrometry (GC-MS). The catalyst calcination temperature determined the optimum conditions. From this study, the conditions necessary for transesterification reaction include the mole ratio of methanol/oil of 6 to 1, the temperature of 70 °C for 2 hours and 700 °C for 5 hours, and catalyst dosage of 2% by weight. Under these conditions, the yield of the biodiesel was 84.26%. Additionally, at the calcination temperature of 800 °C for 7 hours and catalyst dosage of 3% by weight, the yield of the biodiesel was 76.84%. CaO, SiO2, 2CaO.SiO2 and 3CaO.SiO2 were found in the catalyst through XRD analysis. The specific surface areas of the catalyst were 25,497 m2/g (700 °C/5 hours) and 35,879 m2/g (800 °C/7 hours) through BET analysis. According to the GC-MS analysis, the main components of the biodiesel include methyl palmitate, methyl oleate, and methyl stearate.

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Effect of the Ce-TiO2/Diatomite on the Photo-Catalysis Degradation of MB

Materials Science Forum ◽

10.4028/www.scientific.net/msf.789.44 ◽

2014 ◽

Vol 789 ◽

pp. 44-47

Author(s):

Xiu Hong Liang ◽

Xiao Ye Fu

Keyword(s):

Methylene Blue ◽

Uv Light ◽

Sol Gel ◽

Heat Stability ◽

Chemical Action ◽

Methylene Blue Degradation ◽

Photocatalytic Effect ◽

Photo Catalysis ◽

Ft Ir ◽

Physical And Chemical

In this paper, TiO2/diatomite and Ce-TiO2/diatomite were prepared by sol-gel method in order to improve the spectrum responding range and its photocatalytic effect. The obtained samples were characterized by means of X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM), Infrared Absorption Spectroscopy (FT-IR) and so on, and the photocatalytic activity was evaluated by methylene blue degradation. The heat stability of TiO2/diatomite was improved by Ce-doped; TiO2 was successfully loaded on diatomite through physical and chemical action. The de-coloring ratio of methylene blue of the two composite materials were similar under UV light, Ce-TiO2/diatomite was higher under visible light, it reached to 80%, and it kept 65% after the five times repeated using of Ce-TiO2/diatomite.

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Photodegradation of Reactive Red 141 and Reactive Yellow 105 Dyes Using Prepared TiO2 Nanoparticles

Materials Science Forum ◽

10.4028/www.scientific.net/msf.807.65 ◽

2014 ◽

Vol 807 ◽

pp. 65-79 ◽

Cited By ~ 2

Author(s):

Augustine Amalraj ◽

P. Anitha Pius

Keyword(s):

Uv Light ◽

Sol Gel ◽

Operational Parameters ◽

X Ray Diffraction ◽

Pseudo First Order Reaction ◽

Illumination Time ◽

X Ray ◽

Uv Light Irradiation ◽

Sol Gel Process ◽

Dye Solutions

The photodegradation of Reactive Red 141 (RR-141) and Reactive Yellow 105 (RY-105) dyes using TiO2 nanoparticles was investigated under UV light irradiation. TiO2 was prepared by sol-gel process and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) with Energy Dispersive X-ray analysis (EDAX) and FTIR. The effects of operational parameters such as illumination time, catalyst dose, initial concentration and pH of dye solutions on photodegradation by TiO2 have been analyzed. The degradation of the selected dyes followed pseudo-first order reaction according to the Langmuir-Hinshelwood kinetic model.

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ZnFe2O4 Doped TiO2 Photocatalyst Synthesis and Characterization with Effect of Different Coupling Ratios on Band Gap

Journal of the chemical society of pakistan ◽

10.52568/000969/jcsp/43.06.2021 ◽

2021 ◽

Vol 43 (6) ◽

pp. 736-736

Author(s):

Farukh Iqbal Farukh Iqbal ◽

Saad Nadeem Saad Nadeem ◽

Kamran Zakaria and Bawadi Abdullah Kamran Zakaria and Bawadi Abdullah

Keyword(s):

Visible Light ◽

Band Gap ◽

Uv Light ◽

Sol Gel ◽

Visible Region ◽

Xrd Analysis ◽

Phase Identification ◽

Coupling Ratio ◽

Color Mapping ◽

Visible Light Driven

In this work the effect of different coupling ratios of ZnFe2O4 and TiO2 on the band gap was investigated, to convert TiO2 as a visible light driven photocatalyst ZnFe2O4. In this work, ZnFe2O4 was synthesized utilizing sol-gel technique and calcining under normal atmosphere at 900 and#176;C. Thereafter, ZnFe2O4 was coupled with TiO2 by mixing in 50 ml water in three different coupling w/w ratios (1:1, 1:2 and 2:1) followed by the calcination of coupled catalyst under nitrogen environment at 500 and#176;C. XRD, XPS, FESEM-EDS imaging, TGA, UV-Vis, and FTIR were performed to characterize the catalyst. Crystal phase identification could be confirmed through XRD analysis with homogenous distribution of metal constituents through color mapping and surface charge transitions from XPS analysis for a better electron hole generation. Thermogravimetric analysis (TGA) confirmed that the pure ZnFe2O4 obtained at 900 and#176;C, while FTIR verified the presence of desired functional group in ZnFe2O4. Moreover, Fourier Transformation Infrared Spectroscopy (FTIR) illustrated two major peaks and no extra major impurity was detected. ZnFe2O4 is visible light driven photocatalyst and TiO2 can work only under UV light. So, the effect of different coupling ratios of ZnFe2O4 with TiO2 was examined by UV-Vis characterization. The band gap is given by 1:1 was 2.8, 2:1 was 3.17 and 1:2 was 3.02. It was observed that the most optimum coupling ratio is 1:1 and the band-gap fall under visible region. The findings of this work could be supportive significantly for the selection of suitable coupling ratio to convert UV-driven photocatalyst into visible region active photocatalyst.

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Synthesis and Characterization of SiO2/ZnO Core-Shell Spheres

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.320.140 ◽

2011 ◽

Vol 320 ◽

pp. 140-145

Author(s):

Yung Kuan Tseng ◽

Pei Han Wang ◽

Shun Lung Su

Keyword(s):

Uv Light ◽

Spherical Surface ◽

Sol Gel ◽

Xrd Analysis ◽

Core Shell ◽

Visible Absorption ◽

Stöber Method ◽

Eds Analysis ◽

Uv Visible

This Study applies to Stöber method for synthesis an characterization of even-sized SiO2micrometer sphere; and then applies to sol-gel method for encapsulation for one layer of ZnO at SiO2spherical surface after regarded it as core so that synthesis SiO2/ZnO core-shell spheres successfully. And observe morphology by FE-SEM and crossection by TEM. The TEM specimen were cut by two-beam FIB. Besides, EDS, XRD and UV-Visible spectroscopy were using for the analysis of composition, crystallization structure, and absorption spectrum, respectively. Experimental results showed that, SiO2spherical surface became smooth after deposition for zinc oxide. The specimen made by FIB more obviously was observed for core-shell distribution by TEM. EDS analysis made us clearly see shell signal with ZnO content, but core signal only is SiO2content. XRD analysis indicated its core-shell sphere signal possessing ZnO content, but UV-Visible absorption spectrometer displayed ZnO has been absorbed in range of UV light, in contrast, it is not absorbed in range of visible light.

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Optimized Loading of TiO2 Nanoparticles into Electrospun Polyacrylonitrile and Cellulose Acetate Polymer Fibers

Journal of Nanomaterials ◽

10.1155/2020/9429421 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Sibongile C. Nkabinde ◽

Makwena J. Moloto ◽

Kgabo P. Matabola

Keyword(s):

Cellulose Acetate ◽

Anatase Phase ◽

Sol Gel ◽

Polymer Concentration ◽

Emission Spectra ◽

Average Diameter ◽

Xrd Analysis ◽

Polymer Fibers ◽

Electrospinning Technique ◽

Calcination Temperatures

Polyacrylonitrile (PAN), cellulose acetate (CA), PAN-TiO2, and CA-TiO2 nanofibers were prepared using the electrospinning technique under varying the loading of the TiO2 nanoparticles. The latter TiO2 nanoparticles were prepared using the sol-gel method by varying the calcination temperatures. The absorption and emission spectra illustrated the formation of TiO2 nanoparticles with an increase in absorption band edges with smaller particles. The TEM results showed the spherical morphology of the nanoparticles calcined at 500°C with an average diameter of 12.2±3.3 nm. XRD analysis revealed anatase phase as the dominant crystalline phase of the nanoparticles. TiO2 nanoparticle loadings of 0.2 and 0.4 wt% were incorporated into 16 wt% CA solutions while 1, 2, and 3 wt% of TiO2 nanoparticles were incorporated into 10 wt% PAN solutions. The SEM results illustrated the lowering in diameter and morphology of the nanofibers upon incorporation of nanoparticles. Their respective average diameters are 220, 338, 181, and 250 nm for PAN, CA, PAN-TiO2, and CA-TiO2 polymer fibers, respectively. The morphology of the nanofibers improved while the diameter increased with an increase in polymer concentration. Different loadings of TiO2 nanoparticles improved the electrospinnability and morphology and further decreased the size of the nanofibers. FTIR spectroscopy signifies the formation of nanocomposites and the presence of TiO2 nanoparticles which corresponded to the Ti-O stretching and Ti-O-Ti bands on the FTIR spectra.

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Zinc-Doped Titania Embedded on the Surface of Zirconia: A Potential Visible-Responsive Photocatalyst Material

Indonesian Journal of Chemistry ◽

10.22146/ijc.51172 ◽

2020 ◽

Vol 20 (6) ◽

pp. 1374

Author(s):

Azizia Alifi ◽

Rian Kurniawan ◽

Akhmad Syoufian

Keyword(s):

Sol Gel ◽

Diffraction Method ◽

Reflectance Spectroscopy ◽

X Ray Diffraction ◽

X Ray ◽

Calcination Temperatures ◽

Zinc Doping ◽

Doped Titania ◽

Scanning Electron

The preparation and characterization of zirconia-supported titania with a zinc dopant had been studied. Zinc-doped titania was grown on the surface of zirconia by the sol-gel method. Various zinc contents and calcination temperatures were applied to investigate the zinc doping effect and crystal structure of the zirconia-titania composite. X-ray diffraction method, Fourier-transform infrared spectroscopy, and UV-Vis reflectance spectroscopy were performed to characterize the composite. The morphology of the composite was observed by using a scanning electron microscope, and its composition was analyzed by using energy dispersive spectroscopy. Among various zinc dopant contents and calcination temperatures investigated, doping with 5% zinc (Zn wt./Ti wt.) at 900 °C calcination shows the best result in response to visible light with a bandgap of 2.87 eV and absorption edge wavelength of 432.61 nm.

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SYNTHESIS AND CHARACTERIZATION OF Fe2O3 NANOPARTICLES USING Averrhoa bilimbi AS BIOMATERIAL CHELATING AGENT FOR NANOFLUIDS APPLICATION

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.13.2.4348.133-146 ◽

2017 ◽

Vol 13 (2) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

Arie Hardian ◽

Alvi Aristia Ramadhiany ◽

Dani Gustaman Syarif ◽

Senadi Budiman

Keyword(s):

Calcination Temperature ◽

Sol Gel ◽

Chelating Agent ◽

Xrd Analysis ◽

Solid Particles ◽

X Ray Diffraction ◽

Calcination Temperatures ◽

Basic Fluid ◽

Sol Gel Synthesis

The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe2O3 nanoparticles (NPs) in sol-gel synthesis. The obtained Fe2O3 NPs was then used as material for preparation of Fe2O3-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe2O3 have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (Averrhoa bilimbi) extracts as the chelating agent. The calcination temperature was then varied from 500 ºC to 700 ºC for 5 hours. Based on the X-Ray Diffraction (XRD) analysis, the diffraction pattern of obtained Fe2O3 was relevant with the JCPDS data No. 33-0664 for α-Fe2O3 with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe2O3 nanoparticles at calcination temperatures of 500 ºC, 600 ºC and 700 ºC was 50 nm, 48 nm and 40 nm, respectively. The Surface Area of Fe2O3 NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m2/g; 26.91 m2/g and 17.51 m2/g, respectively. Fe2O3-water nanofluids was relativly stable with zeta potential of -39.60 mV; -46.37 mV and -41.57 mV, respectively for 500 ºC, 600 ºC and 700 ºC calcination temperature. The viscosity of Fe2O3-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe2O3 nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe2O3 nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).

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TiO2/Kaolinite Photocatalytic Material of Fe3+ Chemical Doping and Fe2O3 Heat-Banding and its Mechanism Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.178.324 ◽

2010 ◽

Vol 178 ◽

pp. 324-329 ◽

Cited By ~ 2

Author(s):

Chun Hua Bai ◽

Shui Lin Zheng ◽

Zhi Ming Sun ◽

Shao Min Lei ◽

Jing Ya Gui ◽

...

Keyword(s):

Photocatalytic Activity ◽

Uv Light ◽

Low Cost ◽

Sol Gel ◽

Optimum Process ◽

Process Conditions ◽

Chemical Doping ◽

Mechanism Analysis ◽

Photocatalytic Effect ◽

Photocatalytic Material

It is very prospective to prepare low-cost TiO2/nonmetallic minerals photocatalytic material, which utilizes sun as light source to treatment environmental problems. TiO2/kaolinite nanocomposite was prepared by sol-gel method, using layered kaolinite as substrate and Ti(OC4H9)4 as precursor. The optimum process conditions were achieved. In addition, photocatalytic material was modified by mean of Fe3+chemical doping and Fe2O3 heat-banding to enhance photocatalytic activity. AZO-dye wastewater containing Direct Blue and Direct Purple was treated by these two kinds of photocatalyst under UV-light and sunlight separately. The results showed that both methods improved material photocatalytic activity in some way and the photocatalytic efficiency was raised significantly in sunlight as well as in UV-light. The photocatalytic effect of Fe2O3 heat-banding was superior to Fe3+chemical doping. The characterization of SEM, TEM, AFM shown that the 1-10nm anatase TiO2 crystal grain was doped on surface of the kaolinite particles which is as like as ‘forest on the ground’. To further analyze the mechanism of the material, XPS was adopted to analyses the chemical composition, elements, valence state.

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