Decomposition Of Gaseous Benzene Research Articles

Fabrication and Photocatalytic Performance of Titanium Dioxide Nanoparticle/Polymethylmethacrylate

t has been found that the photocatalytic activity of TiOB2B toward the decomposition of gaseous benzene in a batch reactor can be greatly improved by modifying TiOB2 Bin the presence of 3-(trimethoxysilyl) propylmethacrylate (MPS). The prepared photocatalyst (PMMA-TiOB2B) was characterized by FTIR, UV/Vis diffuse reflectance spectroscopy and XPS. PMMA-TiOB2 Bdemonstrates 2.3 times the photocatalytic activity of that of TiOB2B.

Preparation, characterization and photocatalytic performance of TiO 2/Ce xZr 1− xO 2 toward the oxidation of gaseous benzene

Increasing environmental pollution caused by the volatile organic compounds due to their toxicity makes their removal imperative. So it is crucial to develop processes which can degrade these compounds effectively. The paper demonstrates that the photocatalytic activity of TiO 2 toward the decomposition of gaseous benzene in a batch reactor can be greatly enhanced by loading TiO 2 onto the surface of Ce x Zr 1− x O 2 ( x ≥ 0.25) using sol–gel technology. This research investigated the relationship between x amount and the photocatalytic activity of TiO 2. The prepared photocatalysts were characterized by BET, XRD, UV–vis diffuse reflectance and XPS analyses. The specific surface area of photocatalyst decreases as x decreases. XRD results reveal the no peaks of titania were detected. Among the five catalysts prepared, only the binding energy values of Ti2p 3/2 of TiO 2/Ce 0.5Zr 0.5O 2 shift toward lower value. The order of photocatalytic activity is TiO 2/Ce 0.5Zr 0.5O 2 > TiO 2/Ce 0.75Zr 0.25O 2 > TiO 2/CeO 2 ≈ TiO 2/Ce 0.25Zr 0.75O 2 > TiO 2/ZrO 2 ≈ TiO 2. The mechanism role of Ceria–Zirconia mixed oxides in photocatalytic reaction was speculated.

Sol–gel preparation and photocatalytic performance of TiO2/SrAl2O4: Eu2+, Dy3+ toward the oxidation of gaseous benzene

It has been found that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene can be greatly enhanced by loading TiO2 on the surface of SrAl2O4: Eu2+, Dy3+ using sol–gel technology. The prepared photocatalyst was characterized by BET, XRD, and XPS analyses. XRD results reveal that the peaks of titania in either rutile or anatase form are not detected by XRD in the 2θ region from 20° to 50°. The binding energy values of Ti 2p of pure TiO2 are 458.90 and 464.60 eV, while for TiO2/SrAl2O4: Eu2+, Dy3+, the binding energy values of Ti 2p are 458.50 and 464.20 eV. The results indicate that the optimum loading of TiO2 is 1 wt% and TiO2/SrAl2O4: Eu2+, Dy3+ (1 wt%) demonstrates 1.4 times the photocatalytic activity of that of pure TiO2, but the underlying mechanism of SrAl2O4: Eu2+, Dy3+ in the photocatalytic reaction remains to be unraveled.

Characterization and photocatalytic property of Pd/TiO 2 with the oxidation of gaseous benzene

Increasing environmental pollution caused by the volatile organic compounds due to their toxicity is a matter of great concern. So it is crucial to develop processes which can destroy these compounds effectively. It has been found that the photocatalytic activity of TiO 2 towards the decomposition of gaseous benzene can be greatly enhanced by loading Pd on the surface of TiO 2. The results show that the optimum palladium loading is 0.25 wt.%. The prepared photocatalysts were characterized by XRD, UV–vis diffuse reflectance and XPS. XRD results indicate that no peaks of Pd are detected in the 2 θ region from 10° to 90°. Pd/TiO 2 absorbs much more light than TiO 2 in the visible light region. The XPS spectrum shows that there are Ti, O, C and Pd elements on the surface of the Pd/TiO 2, the binding energy values of Ti2p of 0.25%Pd/TiO 2 transfer to a lower value. In addition, the photocatalytic performance of 0.25%Pd/TiO 2 was investigated, the result illustrates that 0.25%Pd/TiO 2 demonstrates 2.32 times the photocatalytic activity of pure TiO 2. The reason of promotion of photocatalytic performance was discussed.

Gas-phase photocatalytic oxidation of benzene over titanium dioxide loaded on Ce0.67Zr0.33O2

Increasing environmental pollution caused by the volatile organic compounds because of their toxicity is a matter of great concern; thus, it is crucial to develop processes that can destroy these compounds effectively. It has been found that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene in a batch reactor can be greatly enhanced by loading TiO2 on the surface of Ce0.67Zr0.33O2. In this work, we have investigated the loading amount of TiO2 on Ce0.67Zr0.33O2 in enhancing the photocatalytic activity of TiO2. This article reveals that the optimal loading amount of TiO2 on Ce0.67Zr0.33O2 for the degradation of gaseous benzene is 1% (wt). The prepared photocatalyst was characterized by Brunauer-Emmet Teller, X-ray diffraction, UV–vis diffuse reflectance, and X-ray photoelectron spectroscopy. The deposited titania was well dispersed in the Ce0.67Zr0.33O2 matrix. TiO2/Ce0.67Zr0.33O2 absorbs much more ultraviolet light than TiO2 in the ultraviolet light region. The binding energy values of Ti2p shift to lower value. TiO2/Ce0.67Zr0.33O2 demonstrates 1.5 times photocatalytic activity of that of pure TiO2. Based upon these observations, the mechanistic role of Ce0.67Zr0.33O2 in the photocatalytic oxidation reaction has been suggested. The suggested mechanism is electrons transfer, increase of the surface coverage of active oxygen species, and increase of the absorption from 210 to 400 nm of TiO2/Ce0.67Zr0.33O2. © 2009 American Institute of Chemical Engineers Environ Prog, 2009

Fabrication and characterization of TiO2/BaAl2O4: Eu2+, Dy3+ and its photocatalytic performance towards oxidation of gaseous benzene

Abstract TiO 2 /BaAl 2 O 4 : Eu 2+ , Dy 3+ photocatalysts were prepared by loading TiO 2 sol on the surface of BaAl 2 O 4 : Eu 2+ , Dy 3+ via sol–gel method. The photocatalytic activity was evaluated by the decomposition of gaseous benzene under UV light illumination. The as-prepared photocatalysts were characterized by nitrogen adsorption–desorption, powder X-ray diffraction and X-ray photoelectron spectroscopy. Results reveal that the optimum loading amount of TiO 2 on BaAl 2 O 4 : Eu 2+ , Dy 3+ can enhance the photocatalytic activities. The BaAl 2 O 4 : Eu 2+ , Dy 3+ samples are all hexagonal phase, the deposited Titania is highly dispersed on the surface of carrier, and a certain interaction exists between TiO 2 and BaAl 2 O 4 : Eu 2+ , Dy 3+ .

Effects of Synthesis Conditions on the Crystalline Phases and Photocatalytic Activities of Silver Vanadates via Hydrothermal Method

AbstractVisible-light-driven Ag3VO4 photocatalysts were successfully synthesized using low-temperature hydrothermal synthesis method. Under various hydrothermal conditions, the structures of silver vanadates were tuned by manipulating the hydrothermal time and the ratio of silver to vanadium. X-ray diffraction (XRD) results reveal that the powders prepared in a stoichiometric ratio consisted of pure α-Ag3VO4 or mixed phases of Ag4V2O7 and α-Ag3VO4. With increasing the Ag-to-V mole ratio to 6:1, the resulting samples were identified as pure monoclinic structure α-Ag3VO4. UV-vis spectroscopy indicated that silver vanadate particles had strong visible light absorption with associated band gaps in the range of 2.2-2.5 eV. The sample synthesized in the excess silver exhibited higher photocatalytic activity than that synthesized in a stoichiometric ratio. The powder synthesized at silver-rich at 140℃ for 4 h (SHT4) exhibited the highest photocatalytic activity among all samples. The reactivity of SHT4 (surface area, 3.52 m2 g-1) on the decomposition of gaseous benzene was about 16 times higher than that of P25 (surface area, 49.04 m2 g-1) under visible light irradiation. A well developed crystallinity of Ag3VO4 of SHT 4 was considered to enhance the photocatalytic efficiency.

Synthesis and Characterization of TiO 2/YFeO 3 and Its Photocatalytic Oxidation of Gaseous Benzene

YFeO 3 was prepared by coprecipitation method and citric acid method, and TiO 2/YFeO 3 heterosystem photocatalysts were synthesized by loading TiO 2 sol on the surface of YFeO 3 via sol-gel method. Their photocatalytic activities were evaluated by the decomposition of gaseous benzene under UV light illumination. The prepared photocatalysts were characterized by nitrogen adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Vis diffuse reflectance spectroscopy. Results revealed that the heterosystem photocatalysts prepared by coprecipitation method showed higher activity, and the maximum conversion of benzene could reach 44.7% within 180 min. The YFeO 3 samples prepared from coprecipitation method and citric acid method were absolutely in orthorhombic phase. The deposited titania was dispersed on the surface of carrier and a certain interaction existed between TiO 2 and YFeO 3. The two heterosystems photocatalysts had narrow band-gap energies.

Effect of metal doping into Ce 0.5Zr 0.5O 2 on photocatalytic activity of TiO 2/Ce 0.45Zr 0.45M 0.1O X (M = Y, La, Mn)

The paper demonstrates that the photocatalytic activity of TiO 2 towards the decomposition of gaseous benzene in a batch reactor can be greatly improved by loading TiO 2 on the surface of CeO 2–ZrO 2. The research investigates the effects of three metals doping into Ce 0.5Zr 0.5O 2 on photocatalytic activity of TiO 2/Ce 0.45Zr 0.45M 0.1O X (M = Y, La, Mn). The prepared photocatalysts were characterized by BET, XRD, UV–vis diffuse reflectance and XPS analyses. BET surface area of TiO 2/Ce 0.45Zr 0.45M 0.1O X (M = Y, La, Mn) is smaller than that of Ce 0.5Zr 0.5O 2. XRD results reveal that the deposited titania is highly dispersed as in the CeO 2–ZrO 2 matrix, doping M in the CeO 2–ZrO 2 lattice causes the changing of lattice space and the diffraction peaks shift to higher 2 θ position. Among these four catalysts, the band gap value of TiO 2/Ce 0.45Zr 0.45La 0.1O X is the lowest. The binding energy value of Ti 2p 3/2 of four catalysts transfers to a lower value. The order of photocatalytic activity is TiO 2/Ce 0.45Zr 0.45La 0.1O X > TiO 2/Ce 0.45Zr 0.45Y 0.1O X > TiO 2/Ce 0.45Zr 0.45Mn 0.1O X > TiO 2/Ce 0.5Zr 0.5O 2 > TiO 2. The proposed mechanism is of electron transfer and the stronger absorption in the region 210–400 nm.

Photocatalytic degradation of gaseous benzene over TiO 2/Sr 2CeO 4: Preparation and photocatalytic behavior of TiO 2/Sr 2CeO 4

The paper demonstrates that the photocatalytic activity of TiO 2 towards the decomposition of gaseous benzene in a batch reactor can be greatly improved by loading TiO 2 on the surface of Sr 2CeO 4. The research investigates the optimum loading amount of TiO 2 on Sr 2CeO 4 in enhancing the photocatalytic activity of TiO 2. The prepared photocatalyst was characterized by XRD, UV–vis diffuse reflectance and XPS analyses. TiO 2 is loaded on Sr 2CeO 4 at 773 K. TiO 2/Sr 2CeO 4 absorbs much more visible light than TiO 2. The XPS spectrum shows that there are Ti, O, C, Sr elements on the surface of the TiO 2/Sr 2CeO 4, and that the binding energy value of Ti2p transfers to a lower value. TiO 2/Sr 2CeO 4 demonstrates 2.0 times the photocatalytic activity of pure TiO 2. Based upon these observations, the mechanistic role of Sr 2CeO 4 in the photocatalytic oxidation reaction has been suggested.