Photocatalytic degradation of aqueous propoxur solution using TiO2 and Hβ zeolite-supported TiO2

Mahalakshmi, M.; Priya, S. Vishnu; Arabindoo, Banumathi; Palanichamy, M.; Murugesan, V.

doi:10.1016/j.jhazmat.2008.03.098

Cited by 127 publications

(70 citation statements)

References 28 publications

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“…4. The broad band between 3,000 and 3800 cm -1 is due to -OH stretching of defective SiOH groups, water and Si-O-Al bridges of [25]. Water bending could be observed at 1638 cm -1 .…”

Section: Effect Of Reaction Timementioning

confidence: 95%

Hβ supported K2CO3 catalysts for dipropyl carbonate synthesis from transesterification route

Zhang

Kang

Shu

et al. 2011

Reac Kinet Mech Cat

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The catalytic performance of the microporous Hb sieve supported K 2 CO 3 catalyst for the synthesis of dipropyl carbonates (DPC) by transesterification of dimethyl carbonate (DMC) with propyl alcohol was investigated at atmospheric pressure, and the optimized reaction conditions were acquired. The catalyst of Hb with 28% K 2 CO 3 -loading performed best, giving 94.4% conversion of DMC and 58.7% selectivity to DPC. An optimum reactant molar ratio n(propyl alcohol)/ n(DMC) existed for catalytic activity, which was about 3/1. The optimum reaction time was 10 h and the suitable reaction temperature was about 363 K considering various factors. The XRD results indicated that the structure of Hb was gradually deformed with the increase in the K 2 CO 3 loading. From nitrogen physisorption, it could be concluded that the improvement of the catalytic activities with the optimized K 2 CO 3 -loading about 28% can be ascribed to both enough active sites and preferable surface area and bigger pore diameter. There was no significant difference between the IR spectrums of K 2 CO 3 /Hb catalyst before and after a 10 h reaction, which was consistent with that K 2 CO 3 /Hb catalyst had excellent utility for repeated use. The possible mechanism of the transesterification reaction was also discussed.

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“…4. The broad band between 3,000 and 3800 cm -1 is due to -OH stretching of defective SiOH groups, water and Si-O-Al bridges of [25]. Water bending could be observed at 1638 cm -1 .…”

Section: Effect Of Reaction Timementioning

confidence: 95%

Hβ supported K2CO3 catalysts for dipropyl carbonate synthesis from transesterification route

Zhang

Kang

Shu

et al. 2011

Reac Kinet Mech Cat

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“…Therefore, several attempts were performed to enhance the photocatalytic activity of TiO 2 . These include doping of transition metals into the surface of TiO 2 (Nahar, Hasegawa, Kagaya, & Kuroda, 2007;Wang, Ye, Wu, & Hu, 2008), acid pre-treatment of the anatase surface (Colon, Sanchez-Espana, Hidalgo, & Navio, 2006), impregnation with different dyestuff and complexes (Escobar, et al, 2008;Kawamura, Okuto, Taruta, Takusagawa, & Kitajima, 1996;Moon, Yun, Chung, Kang, & Yi, 2003), modification with other semiconductors (Ma, Brown, Howe, Overbury, & Dai, 2008) or supporting on surface of activated carbon, aluminosilicates and zeolite (Gan, Liu, Zhang, & Chen, 2008;Jayasankar, Ananthakumar, Mukundan, Wunderlich, & Warrier, 2008;Mahalakshmi, Vishnu Priya, Arabindoo, Palanichamy, & Murugesan, 2008;Razavi, Rahimipour, & Kaboli, 2008;Yang, Liu, Yang, & Yu, 2008).…”

Section: Ho Andmentioning

confidence: 99%

Photocatalytic Degradation of Phenol using Fe-TiO2 by Different Illumination Sources

Shawabkeh¹,

Khashman²,

Bisharat³

2010

IJC

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A Fe-doped titanium dioxide (Fe-TiO 2 ) was prepared using hydrothermal method and used for degradation of phenol from aqueous solution. The samples were characterized by X-ray diffraction (XRD) and showed a presence of both TiO 2 and Fe 2 O 3 peaks. The photocatalytic activity of Fe-TiO 2 catalyst was evaluated for oxidation of phenol in aqueous solution using different illumination sources. Visible light irradiation from sun, UV light sources with 190 and 390 nm, fluorescence and dark environment were used and found that the degradation of phenol was in the order of 7.8%, 12%, 7.5%, 6.8% and 5% obtained after 24 h, respectively. It was found that the increase in exposure time to UV, the increase in solution temperature and pH have increased the rate of phenol degradation in solution. This rate was best fitted using first order kinetic model with reaction constant of 3 10 268 . 6 − × .

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“…Zeolites are especially suitable as adsorbents for this purpose due to their high specific surface area, tunable hydrophobic/hydrophilic surface properties, availability on an industrial scale and low environmental impact [28][29][30]. Guo et al [31] prepared composites of ZSM-5 with different n Si /n Al ratios of 500, 200 and 25 with TiO 2 (P25) using a solid-state dispersion method.…”

Section: Introductionmentioning

confidence: 99%

“…Applying a composite of zeolite ZSM-5 loaded with as little as 8 wt.% of TiO 2 resulted in a significant increase of photodegradation of formaldehyde and trichloroethylene among the other composites and pure TiO 2 . In addition, the role of zeolite H-beta in composites with TiO 2 in the photocatalytic degradation of an aqueous propoxur solution was shown to rely on concentrating the reactants and intermediates within its cavities and a subsequent and continuous supply to the TiO 2 surface [28].…”

Section: Introductionmentioning

confidence: 99%

Photocatalytic Oxidation of NO over Composites of Titanium Dioxide and Zeolite ZSM-5

2016

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Abstract:Composites of TiO 2 (Hombikat, P25, sol-gel synthesis) and zeolite ZSM-5 (n Si /n Al = 55) with mass fractions from 25/75 to 75/25 were prepared by mechanical mixing, solid-state dispersion and sol-gel synthesis. Characterization of the composites by X-ray diffraction (XRD), N 2 -sorption, scanning electron microscopy (SEM), and UV-Vis spectroscopy show that mechanical mixing and solid-state dispersion lead to comparable textural properties of the composites. A homogeneous distribution and intimate contact of small TiO 2 particles on the crystal surface of zeolite ZSM-5 were achieved by sol-gel synthesis. The composites were studied in the photocatalytic oxidation (PCO) of NO in a flatbed reactor under continuous flow according to ISO 22197-1. The highest NO conversion of 41% at an NO 2 selectivity as low as 19% stable for 24 h on-stream was reached over the TiO 2 /ZSM-5 composite from sol-gel synthesis with equal amounts of the two components after calcination at 523 K. The higher activity and stability for complete NO oxidation than for pure TiO 2 from sol-gel synthesis, Hombikat, or P25 is attributed to the adsorptive properties of the zeolite ZSM-5 in the composite catalyst. Increasing the calcination temperature up to 823 K leads to larger TiO 2 particles and a lower photocatalytic activity.

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Photocatalytic degradation of aqueous propoxur solution using TiO2 and Hβ zeolite-supported TiO2

Cited by 127 publications

References 28 publications

Hβ supported K2CO3 catalysts for dipropyl carbonate synthesis from transesterification route

Hβ supported K2CO3 catalysts for dipropyl carbonate synthesis from transesterification route

Photocatalytic Degradation of Phenol using Fe-TiO2 by Different Illumination Sources

Photocatalytic Oxidation of NO over Composites of Titanium Dioxide and Zeolite ZSM-5

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