Immobilization of Nano-TiO2 on Expanded Perlite for Photocatalytic Degradation of Rhodamine B

2011 ◽  
Vol 110-116 ◽  
pp. 3795-3800 ◽  
Author(s):  
Xiao Zhi Wang ◽  
Wei Wei Yong ◽  
Wei Qin Yin ◽  
Ke Feng ◽  
Rong Guo

Expanded perlite (EP) modified titanium dioxide (TiO2) with different loading times were prepared by Sol-Gel method. Photocatalytic degradation kinetics of Rhodamine B (RhB) in polluted water by the materials (EP-nanoTiO2), as well as the effects of different loading times and the initial concentration of RhB on photocatalysis rate were examined. The catalytic activity of the regenerated photocatalyst was also tested. The results showed that photocatalyst modified three times with TiO2had the highest catalytic activity. Degradation ratio of RhB by EP-nanoTiO2(modified three times) under irradiation for 6 h were 98.0%, 75.6% and 63.2% for 10 mg/L, 20 mg/L and 30 mg/L, respectively.The photocatalyst activity has little change after the five times recycling, and the degradation rate of RhB decreased less than 8%. The reaction of photocatalysis for RhB with irradiation time can be expressed as first-order kinetic mode within the initial concentration range of RhB between 10mg/L and 30 mg/L. EP-nanoTiO2photocatalyst has a higher activity and stability to degrade RhB in aqueous solution.

2013 ◽  
Vol 709 ◽  
pp. 70-73
Author(s):  
Guo Bin Duan ◽  
Yong Kui Huang ◽  
Li Yu ◽  
Shui Jin Yang

H3PW6Mo6O40/SiO2 was prepared by sol-gel method, and sensitized by H2O2 solution. The photocatalytic degradation of methyl violet by H3PW6Mo6O40/SiO2 under simulated natural light irradiation was investigated. The results demonstrated that at optimal condition (initial concentration of methyl violet is 10 mg/L, and the pH is 2.5, the dosage of catalyst is 0.5% based on feed stocks), the degradation rate of methyl violet is as high as 88.7 % after 2.5h simulated natural light irradiation. The reaction of photocatalysis for methyl violet can be expressed as first-order kinetic model.


Author(s):  
Carina Chun Pei ◽  
Wallace Woon-Fong Leung ◽  
Lijun Yang ◽  
Chi-ho Hung

Photocatalytic reduction of contaminants in wastewater or polluted water can be enhanced by finding a suitable catalyst with property that utilizes an extended light adsorption spectrum, reducing the recombination of electron-hole pairs, and casting the catalyst into a form with large surface-to-volume ratio to be in contact with the contaminants. Based on these objectives, Zn-doped TiO2 nanoparticles with high photocatalytic activity were synthesized by the sol–gel assisted nozzle-less electrospinning technique followed by calcining the precursor Ti(OiPr)4/ZnAc/PVP nanofibers in air in the temperature range of 450–650°. The thermal decomposition behavior was studied by thermogravimetric analyser and differential scanning calorimeter (TGA–DSC), and the morphology and crystal structure were monitored by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). With the different concentration of zinc acetate in the precursor solution, the diameter of fibers ranged from 80–130 nm. The photocatalytic degradation of rhodamine B dye under visible light irradiation was also studied. It is found that the photosensitized degradation activity can be optimized by doping an appropriate amount of Zn (0.30 wt. %). Hence, the enhanced photodegradation of dyes with a new photocatalyst nanofiber under visible irradiation can be realized, which can take better use of solar energy.


2012 ◽  
Vol 535-537 ◽  
pp. 2220-2223 ◽  
Author(s):  
Xing Jin ◽  
Jin Lan Lian ◽  
Yu Qiao

Lanthanum doping TiO2 powders were prepared using sol-gel method, and characterized by XRD. The doping quantity, time of solar irradiation and the added quantity of catalyst were investigated for the influence on the photocatalytic degradation of bisphenol A. The results show the structure of La3+ doped TiO2 powders were anatase, particle size were 16 nm. For the initial concentration of bisphenol A solution were 50 mg/L , when the doping quantity of La were 1.0 wt %, the dosing quantity of TiO2 were3.6 g/L, PH value were acid, irradiation time were 2 h, the photocatalytic activity of TiO2 was the best.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Shuijin Yang ◽  
Yongkui Huang ◽  
Yunzhi Wang ◽  
Yun Yang ◽  
Mingbo Xu ◽  
...  

In order to remove aquatic organic dye contaminants by utilizing the inexpensive and inexhaustible solar energy, the Keggin-type H3PW12O40was loaded on the surface of SiO2with the sol-gel method and sensitized by H2O2solution. The photocatalytic degradation of rhodamine B (RhB) by H3PW12O40/SiO2(x) under simulated natural light irradiation was investigated. The effects of the initial RhB concentration, the solution pH, and catalyst dosage on the photocatalytic degradation rate of RhB were also studied. The results demonstrated that at optimal condition (initial concentration of methyl orange is 10 mg/L, catalyst dosage is 0.8 g, and the pH is 2.5) the degradation rate of RhB is as high as 97.7% after 2 h under simulated natural light irradiation. The reaction of photocatalysis for RhB can be expressed as a first-order kinetic model.


2019 ◽  
Vol 233 (5) ◽  
pp. 595-607 ◽  
Author(s):  
Mohsin Siddique ◽  
Noor Muhammad Khan ◽  
Muhammad Saeed

Abstract Nanosized, magnetically separable bismuth ferrite (BFO) nanoparticles, pertaining a crystallite size in the range of 14–15 nm were prepared via facile sol-gel technique. The product was characterized by scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The product was explored for the photocatalytic mineralization of rhodamine B (RB) dye in aqueous medium. The effect of different investigational parameters such as amount of photocatalyst, initial dye concentration and irradiation time on the photocatalytic degradation of RB was studied. The results reveal that the catalyst shows good degrading ability under normal pH and visible light conditions. BFO nanoparticles demonstrated a strong absorption ability in the visible-light region, which lead to efficient photocatalytic degradation of RB dye The reaction system was heterogeneous in nature in which the catalyst can be separated by a normal magnet.


NANO ◽  
2008 ◽  
Vol 03 (05) ◽  
pp. 317-322 ◽  
Author(s):  
ZHAOHUI LUO ◽  
KEIKO KATAYAMA-HIRAYAMA ◽  
KIMIAKI HIRAYAMA ◽  
TETSUYA AKITSU ◽  
HIDEHIRO KANEKO

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.


2017 ◽  
Vol 863 ◽  
pp. 20-25 ◽  
Author(s):  
Jing Li Gao ◽  
Ying Hui Han ◽  
Yu Juan Li ◽  
Xiao Hong Zhang

Photocatalytic degradation kinetics of methylene blue in aqueous solution was systematically investigated using Ti-based composite material as the photocatalyst. The single-variable-at-a-time ( SVAT) method was employed. It studied the individual and synergistic effects of several classical parameters on photocatalytic efficiencies. The kinetic mechanism was systematically explored. The kinetics effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The factors on the degradation of MB were in accordance with the pseudo first order kinetic model. This kinetic model followed the Langmuir–Hinshelwood model. The best preparation conditions were found in the experiments. It is proved that the Ti-based composite material is an effective adsorbent for the degradation of dye contaminated water.


CrystEngComm ◽  
2016 ◽  
Vol 18 (11) ◽  
pp. 1964-1975 ◽  
Author(s):  
Xu Liu ◽  
Yuxiu Li ◽  
Dongyang Deng ◽  
Nan Chen ◽  
Xinxin Xing ◽  
...  

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